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C.A.P.E. Estuaries Management Programme 

UILKRAALS ESTUARY 

SITUATION ASSESSMENT 

DRAFT 

JULY 2010 

ENVIRONMENTAL 

ANCH R 

University of Cape Town, 

PO Box 34035, Rhodes Gift 7707 

barry.clark@uct.ac.za 

E N V I R O N M E N T A L 

• marine & estuarine ecology • aquatic resource management • 

• resource economics • conservation planning • 

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EXECUTIVE SUMMARY 

Introduction 

The Uilkraals Estuary is a relatively large estuary, with a total area of 105 ha, and is located on the 

Southern Cape Coast of South Africa. The Uilkraals is an important estuary from a conservation 

perspective, particularly in respect of macrophyte diversity and bird fauna. The large expanse of sand 

and mud flats as well as the high plant diversity within the estuary makes the Uilkraals, together with the 

Klein and Heuningnes Estuaries, unique along the Southern Cape Coastline. The estuary faces pressure 

from reduced freshwater inflow due to the upstream Kraaibosch Dam, planned rural developments and 

increasing tourism at the estuary mouth. Recognising the importance of the Uilkraals Estuary and 

estuaries in South Africa more generally, the C.A.P.E. Regional Estuaries Management Programme 

commissioned Anchor Environmental Consultants cc to prepare a management plan for the Uilkraals 

Estuary. This report is the Situation Assessment that forms the background material for the development 

of the management plan, and should be read in conjunction with the Management Plan itself. 

Geographic and socio-economic context 

The Uilkraals Estuary is situated approximately 60 km northwest of Cape Agulhas and 11 km east of 

Danger Point on the south-west coast of South Africa. It is the first estuary east of Danger Point and lies 

within the warm-temperate biogeographic region of South Africa. The catchment lies entirely within the 

Western Cape Province which receives most precipitation during the winter rainfall season. The estuary is 

classified as a temporarily open-closed mixed blackwater system, which is relatively common along the 

south west and east coast. The Mean Annual Runoff (MAR) is approximately 18 Mm 3 , which is 20% lower 

than under natural conditions. The Kraaibosch Dam was built 10 km upstream of the estuary in 1999, 

covers a surface area of 102 ha and has a storage capacity of 5.5 Mm 3 . Numerous smaller farm dams are 

found throughout parts of the catchment too. 

The total population living within the Overstrand Local Municipality, in which the Uilkraals River 

Catchment is located, was estimated at 74 546 in the 2007 StatsSA Community Survey. The population 

density was estimated at 35 people per square kilometre and the total household count was 24 485. The 

overall population of the Uilkraals River catchment (G40M) is a small proportion of the total for the 

Overstrand local municipality, as it contains a small urban area. Larger settlements such as Gansbaai with 

approximately 20 000 residents and Stanford with 8 000 residents are located outside of the boundaries 

of the Uilkraals catchment. Agriculture, residential development and nature conservation are the main 

land use activities in the catchment. The Uilkraals Estuary and surrounding areas are aesthetically 

beautiful and this remains a strong draw card to the estuary. 

Ecological characteristics and functioning of the estuary 

The Uilkraals Estuary is important in terms of its conservation value. Based on an index which takes size, 

estuary type, rarity and biodiversity (plants, invertebrates, fish, birds) into account, the estuary was 

ranked 34 th overall in terms of conservation importance in South Africa (Turpie et al. 2002). 

Structures associated with the estuary include a bridge approximately 220 m long which crosses the river 

approximately 800 m from the mouth. The bridge was constructed in 1973 and replaced an old wooden 

footbridge (Heydorn & Bickerton 1982). It is supported on the eastern side by a high embankment of 

Uilkraals Estuary Situation Assessment 

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Anchor Environmental

ubble spanning almost two-thirds of the original high tide river width (Gaigher 1984). The remaining 

100 m is supported by concrete pylons, effectively halving the width of the estuary there and 

concentrating the river flow against the western bank (Heydorn & Bickerton 1982). The lower reaches of 

the estuary used to consist of several braided channels that expanded to a single 400 m wide channel at 

high tide (Harrison et al. 1995b). Water in the area below the bridge is now restricted to two smaller 

shallow channels, the larger of which ends at the beach in front of the huts at the caravan park. 

Some very short mouth closure events have occurred in the past with the estuary remaining closed for 

only brief periods of time (Gaigher 1984). The first time (in recorded history) the mouth of the estuary 

closed for an extended period of time was in January 2009. It only opened again in the winter of the 

same year (P. Le Roux, pers. comm.). The opening may have been caused by residents manually digging a 

channel to connect it to the sea, as the mouth closed shortly after and has been closed ever since. Before 

mouth closure occurred, tidal influence reached beyond the bridge, with the majority of the sandflats 

becoming inundated at high tide (Harrison et al. 1995b). Tidal interchange was recorded up to 3 km 

upstream in a 1981 survey (Heydorn & Bickerton 1982). Currently, a very shallow braided channel runs 

across the sandflats upstream from the bridge, probably similar to former low tide conditions. The 

majority of the sandflats are now permanently exposed. The middle reaches of the estuary consist of a 

wide meandering channel across a large floodplain, surrounded by saltmarsh vegetation. 

Vegetation of the estuary can broadly be grouped into four types: (1) Macroalgae (Enteromorpha sp.) 

which forms extensive mats that cover sand and mud flats in the lower reaches of the estuary, and is a 

source of concern owing to the impacts on invertebrate populations and their predators (birds). (2) 

Submerged macrophytes consist of eelgrass Zostera capensis, which forms beds in the lower reaches and 

provide important habitat for juvenile fishes. (3) Salt marsh, which is also concentrated in the lower 

reaches and on the floodplain area, contributes to system productivity and biotic diversity, providing 

important feeding areas, habitat and shelter for numerous invertebrates, birds and fish. (4) Reeds and 

sedges, which are not able to tolerate high salinity, occur in the middle and upper reaches of the estuary. 

Fish are particularly reliant on estuaries for sheltered habitat in southern Africa, and different species 

depend on them to different extents. Previous studies, for example Harrison et al. (1995b), recorded four 

species of fish in the estuary; Cape silverside Atherina breviceps, Knysna sand goby Psammogobius 

knysnaensis, harder Liza richardsonii, and flathead mullet Mugil cephalus. An icthyological survey carried 

out in 2006 found 11 different species through seine net hauls. The Knysna sand goby is the most 

abundant species in the estuary, followed by harders. In all, nine species (82% of the fish species 

recorded from the Uilkraals Estuary) are regarded as either partially or completely dependent on 

estuaries for their survival. Another five of the species recorded are at least partially dependent on 

estuaries as a nursery area including cape sole Heteromycteris capensis, groovy mullet Liza dumerilii, 

blackhand sole Soleo bleekeri, harder Liza richardsonii and white stumpnose Rhabdosargus globiceps. 

The Uilkraals Estuary is an important area for waterbirds (Barnes 1996). On a national scale it ranked 14 th 

in terms of waterbird abundance in a conservation priority analysis study (Turpie 1995). Regionally, it 

was ranked 11 th out of 65 coastal wetland systems in the south-western Cape in terms of bird numbers 

supported (Ryan et al. 1988). A total of 48 water-associated bird species have been recorded at the 

Uilkraals Estuary. Of these, 23 species are piscivorous, 21 are invertebrate-feeding and four species are 

herbivorous. The estuary has supported large numbers of terns and migratory waders in the past 

(Summers et al. 1976, Heydorn & Bickerton 1982, Ryan et al. 1988) and has been recognised as one of the 

largest mainland tern roosts in the south-western Cape (Ryan et al. 1988). However, recent bird counts 

suggest that certain bird species visiting the estuary have decreased dramatically. Previous years have 


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seen hundreds and even thousands of waders and terns around the estuary. In February 2010 a total of 

only 60 waders were counted. This is most likely due to a loss in the intertidal feeding habitat which 

covered the entire sandlfat region below and above the causeway. The estuary also seems to have 

become less suitable as a tern roosting site. 

The Uilkraals Estuary is now categorised as a D-class estuary in terms of its present state of health. This 

means it is considered to be a ”largely modified” system. Although the estuary currently receives 80% of 

its Mean Annual Runoff (MAR), the loss of an important part of the natural hydrology of the estuary has 

been removed (winter and summer base flows), which has modified the natural condition and caused the 

estuary to become permanently closed off from the sea. This has resulted in changes to the habitats 

within and around the estuary (i.e. microalgae abundance and saltmarsh areas) and has caused a 

decrease in the number of bird species, especially waders utilising the estuary. It is likely that the 

estuary’s condition will continue to deteriorate. Turpie & Clark (2007) listed the Uilkraals Estuary as a 

high priority estuary for rehabilitation. Alien plant clearance and the removal of the causeway were 

listed as the types of requirements needed to rehabilitate the estuary. Increasing the freshwater inflows 

and ensuring more natural flows into the system are also needed. 

Ecosystem services 

Estuaries provide a range of services that have economic or welfare value. In the case of the Uilkraals 

Estuary, the most important of these are the recreational and tourism values of the estuary as well as the 

provision of a nursery area for fish. There may be additional services, such as carbon sequestration, but 

these are not likely to be of major value. 

The Uilkraals Estuary is a popular tourist destination for local and regional South African tourists. The 

area surrounding the mouth of the estuary has been developed on the west bank in the form of the 

Uilenkraalsmond Holiday Resort, which includes the municipal caravan and camping park as well as 

associated recreational amenities located on the site. This establishment is generally full during the 

major holiday periods. Birding and recreational opportunities represent an important draw card for 

visitors to the estuary. 

Legislation and management issues 

Little legislation has been designed for estuaries in particular. However, the fact that estuaries contain 

freshwater, terrestrial and marine components, and are heavily influenced by activities in a much broader 

catchment and adjacent marine area, means that they are affected by a large number of policies and 

laws. There is also no specific provision for Estuarine Protected Areas. The Department of Water and 

Environmental Affairs Estuary is the primary agency responsible for estuary management in South Africa 

with a small amount of responsibility (fisheries) attributable to the Deapartment of Agriculture and 

Fishies. Environmental management in most instances is devolved to provincial level, aside from water 

resources and fisheries which remain a national competancy. At a municipal level, by-laws are passed 

which cannot conflict with provincial and national laws. The Uilkraals Estuary lies wholly within the 

Overstrand Local Municipality, which falls within the Overberg District Municipality of the Western Cape 

Province. 

Water quality and quantity are mainly controlled under the National Water Act 36 of 1998. This makes 

provision for an Environmental Reserve which stipulates the quantity and quality of water flow required 

to protect the natural functioning of each water resource, including estuaries. The extent to which an 


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estuary’s functioning is catered for is determined by the designated future management “class” (where 

classes A – F describe state of health), called the Ecological Reserve Category (ERC). In future this will be 

determined in a recently-developed, holistic classification process. 

Exploitation of living resources in the estuary is governed by the Marine Fisheries Policy for South Africa 

(1997) and the Marine Living Resources Act (1998). The policy supports sustainable use of resources and 

use of these resources for economic growth and development as well as ecosystem and biodiversity 

protection. 

The Integrated Coastal Management Act, 2008 (ICMA) requires that a management plan be developed for 

each estuary in the country. ICMA also requires the designation of a coastal protection zones extending 

100 m from the high tide mark (including in estuaries) in areas zoned for residential, industrial or 

commercial land use, and much larger development setback of 1km for public land and land zoned for 

agricultural use. A development setback zone must also be designated for all coastal property, by 

agreement between local and provincial authorities. Within these designated setback zones, no new land 

transformation or development may take place without a permit issued by the MEC. There is also 

provision to create a larger setback line under the ICMA where necessary. In the case of the Uilkraals 

Estuary, most of the land surrounding the estuary is zoned rural, and thus in terms of ICMA a coastal 

protection zone of 1km will be required around much of the estuary. There is a strong argument to 

establish corresponding development setback zones for all estuaries in the country. 

The Municipal Systems Act (2000) requires the identification of development priorities for each province, 

district and local municipality, and the expression of development plans in a spatial layout. The latter in 

turn, has to be formalised in a detailed land use and management plan. Thus the key land-use decisionmaking 

is taking place by the local municipalities, in this case the Overstrand Local Municipality. Their 

plans have to fit in with broader scale plans of the district and province. The Western Cape Province 

Spatial Development Framework (SDF) highlights the conservation importance of the Uilkraals Estuary at 

a national level but offers little of specific relevance to the management of the Uilkraals Estuary. The 

Overberg District and Overstrand Local Municipality IDP and SDF documents offer more relevance at a 

local management level. Both SDF documents highlighted the importance of conservation areas and the 

need for protection of biodiversity and ecosystem functioning. Two strategies mentioned in both SDF 

documents key to restoration or rehabilitation of the Uilkraals Estuary, is the importance of and need for 

alien invasive plant clearance along the course of the river and estuary, as well the importance of 

regulating any modification of rivers and their natural flow patterns. Effective management of the 

catchment needs to be ensured. The local Overstrand SDF document focuses on a spatial planning 

concept that underpins the municipality’s approach to the integrated spatial management of land use 

and economic development within its area. The main principles involve identifying an overarching spatial 

development pattern within a clear hierarchy of nodes and settlements, the hierarchy of the 

development patterns being clearly defined based on empirical determined growth potentials, the 

principles of comparative advantage and the prerequisite of sustainable development. The growth of 

urban nodes and rural settlements should be strictly contained within well-defined boundaries and 

growth should be managed so as to ensure that development pressures are, wherever possible, directed 

and absorbed within the defined urban areas. Appropriate densification specific to each area must be 

encouraged to limit unwanted sprawl into the rural vicinity. The diversity, health and productivity of 

natural eco-systems, throughout the rural, urban and agricultural areas should be maintained through an 

interlinked web of natural spaces and the protection of important sensitive habitats. 


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Need for protection of the Uilkraals Estuary 

The Uilkraals Estuary is important in terms of its conservation value. It has unique macrophyte diversity 

and is a very important birding site. The Uilkraals Estuary was included within a set of estuaries in the 

country identified as requiring protection in order to achieve national biodiversity protection targets. The 

establishment of a protected area on the Uilkraals Estuary is highly recommended and is considered 

highly feasible. Specific recommendations, to be further developed in consultation with stakeholders, are 

as follows: 

1. Establish a nature reserve encompassing as much of the land around the estuary as possible 

including supratidal estuarine habitats; 

2. Establish a Marine Protected Area on the estuary incorporating the most significant bird 

habitats and fish nursery areas as well as a representative section of all habitat types present 

in the estuary (mudflat, salt marsh, submerged and emergent vegetation) 

3. Develop a zonation plan in which 50% of the MPA (not necessarily contiguous) is declared a 

no-take zone. 

The Uilkraals Estuary has also been identified as one in which there is a need for rehabilitation. Key 

management interventions identified in this respect include: 

1. Restoration of the quantity of freshwater inflows; 

2. Restoration of water quality; 

3. Removing significant obstructions to flow; and 

4. Removal of alien vegetation 

The degree to which these factors should be managed to restore the health of the system depends 

largely on the vision that is developed for the estuary, and on its future protection status. 


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ABBREVIATIONS AND ACRONYMS 

WMA 

BAS 

C.A.P.E. 

Chla 

CPUE 

DEA&DP 

DEAT 

DIN 

DRP 

DRS 

DWAF 

ERC 

EHI 

EWR 

HIV/AIDS 

IDP 

IEP 

NEMA 

NWA 

MAR 

MCM 

MEC 

Mm 3 

MSL 

PES 

RDM 

REI 

RSA 

RQO 

SDF 

TPC 

WCNCB 

Water Management Area 

Best Attainable State 

Cape Action Plan for People and the Environment 

Chlorophyll a 

Catch per unit effort 

Department of Environmental Affairs and Development Planning (provincial) 

Department of Environmental Affairs and Tourism (national) 

Dissolved Inorganic Nitrogen 

Dissolved Reactive Phosphate 

Dissolved Reactive Silicate 

Department of Water Affairs and Forestry 

Ecological Reserve Category 

Estuary Health Index 

Ecological Water Requirement 

Human Immunodeficiency Virus/Acquired Immunodeficiency Disease Syndrome 

Integrated Development Planning 

Integrated Environmental Programme 

National Environmental Management Act 

National Water Act 

Mean Annual Runoff 

Marine & Coastal Management 

Member of provincial Executive Council 

Million cubic metres 

Mean Sea Level 

Present Ecological Status 

Resource Directed Measures 

River-Estuary-Interface 

Republic of South Africa 

Resource Quality Objectives 

Spatial Development Framework 

Threshold of Potential Concern 

Western Cape Nature Conservation Board 


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TABLE OF CONTENTS 

1. INTRODUCTION ........................................................................................................................... 9 

2. GEOGRAPHIC AND SOCIO-ECONOMIC CONTEXT ....................................................................... 11 

2.1 LOCATION AND EXTENT OF THE ESTUARY AND ITS CATCHMENT ....................................................................... 11 

2.2 CATCHMENT CLIMATE, VEGETATION AND DRAINAGE .................................................................................... 13 

2.3 CATCHMENT POPULATION, LAND-USE AND ECONOMY.................................................................................. 15 

Population and socio-economic status ............................................................................................ 15 

Land-use .......................................................................................................................................... 16 

Economy .......................................................................................................................................... 17 

3. ECOLOGICAL CHARACTERISTICS AND FUNCTIONING OF THE ESTUARY ...................................... 18 

3.1 MOUTH DYNAMICS, HYDROLOGY AND CHANNEL SHAPE ................................................................................ 18 

3.2 WATER CHEMISTRY ............................................................................................................................... 22 

3.3 MICROALGAE ...................................................................................................................................... 22 

3.4 VEGETATION ....................................................................................................................................... 23 

Macroalgae ..................................................................................................................................... 23 

Submerged macrophytes................................................................................................................. 23 

Salt marsh ....................................................................................................................................... 23 

Reeds and sedges ............................................................................................................................ 24 

Terrestrial vegetation ...................................................................................................................... 24 

3.5 INVERTEBRATES ................................................................................................................................... 25 

Benthic invertebrates ...................................................................................................................... 25 

Hyperbenthic invertebrates ............................................................................................................. 25 

3.6 FISH .................................................................................................................................................. 26 

3.7 BIRDS ................................................................................................................................................ 28 

3.8 CURRENT HEALTH OF THE ESTUARY .......................................................................................................... 31 

Implications for the estuary ............................................................................................................ 33 

4. ECOSYSTEM SERVICES ............................................................................................................... 34 

4.1 WHAT ARE ECOSYSTEM SERVICES ........................................................................................................... 34 

4.2 GOODS AND SERVICES PROVIDED BY THE UILKRAALS ESTUARY ....................................................................... 34 

4.3 RAW MATERIALS .................................................................................................................................. 35 

4.4 CARBON SEQUESTRATION ...................................................................................................................... 35 

4.5 WASTE TREATMENT .............................................................................................................................. 36 

4.6 EXPORT OF MATERIALS AND NUTRIENTS .................................................................................................... 36 

4.7 REFUGIA AREAS AND NURSERY VALUE ....................................................................................................... 36 

4.8 GENETIC RESOURCES ............................................................................................................................. 38 

4.9 TOURISM AND RECREATIONAL VALUE ....................................................................................................... 38 

5. LEGISLATION AND MANAGEMENT ISSUES ................................................................................. 40 

5.1 THE MAIN THREATS AND OPPORTUNITIES TO BE CONSIDERED ........................................................................ 40 

5.2 GENERAL POLICY AND LEGISLATIVE BACKGROUND ....................................................................................... 40 

5.3 WATER QUANTITY AND QUALITY REQUIREMENTS ........................................................................................ 47 

Legislative context ........................................................................................................................... 47 

The classification process ................................................................................................................ 47 


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The reserve determination process ................................................................................................. 47 

5.4 EXPLOITATION OF LIVING MARINE RESOURCES ............................................................................................ 48 


Issues surrounding recreational fishing ........................................................................................... 48 

5.5 LAND USE AND MANAGEMENT OF ESTUARY MARGINS .................................................................................. 48 


Development planning pertaining to the Uilkraals Estuary ............................................................ 53 

Issues of surrounding land use and development ........................................................................... 66 

5.6 NON-CONSUMPTIVE RECREATIONAL USE ................................................................................................... 66 

Legislation ....................................................................................................................................... 66 

Management issues ........................................................................................................................ 66 

5.7 POTENTIAL FOR PROTECTED AREA STATUS ................................................................................................. 67 


Potential for protection of the Uilkraals Estuary ............................................................................. 68 

Recommendations and procedure for establishing a protected area ............................................. 68 

5.8 POTENTIAL AND NEED FOR RESTORATION ON THE UILKRAALS ESTUARY ........................................................... 69 

6. REFERENCES .............................................................................................................................. 70 


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1. INTRODUCTION 

The Uilkraals Estuary is one of South Africa’s approximately 279 functional estuaries (Turpie 

2004). It is one of 21 estuaries within the warm temperate biogeographical region to be 

classified as a temporarily open/closed, mixed blackwater system (van Niekerk & Taljaard 

2007). A medium to large sized estuary, it is estimated to cover an area of 105 ha (Turpie & 

Clark 2007) (Figure 1), and before the construction of the upstream Kraaibosch Dam had 

naturally hyposaline conditions and a strong tidal exchange when open to the sea. This tidal 

exchange helped to maintain an open mouth state (Harrison et al. 1995b), but since the 

construction of the dam in 1999, there has been a disruption in the natural freshwater inflows. 

Owing to its large size, high diversity and abundance of certain biota, the estuary is rated as 

34 th overall in terms of conservation importance in South Africa (Turpie et al. 2002, Turpie & 

Clark 2007). It has been identified as a particularly important estuary for macrophyte diversity 

(macroalgae, submerged macrophytes and saltmarsh) and birds (both residential and migrants) 

(Barnes 1996). 

Figure 1: The Uilkraals Estuary before it became closed to the sea (Source: Google Earth). 

Despite the widely acknowledged conservation importance of the Uilkraals Estuary, the system 

is currently under no formal protection. The estuary has been subjected to relatively high 

levels of development and anthropogenic disturbance. This includes the construction of the 

road bridge over the estuary which affected the natural east to west migration of the mouth. 

Increasing recreational use of the estuary, including natural resource use (such as fishing) and 

non-consumptive activities (birdwatching and hiking) is putting pressure on the system, which 

will most likely see a change in the character of the area. However, the most significant impact 

has been the reduction in freshwater flow into the estuary due to water storage. The 


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construction of the Kraaibosch dam some 10 km upstream from the estuary in 1999 has 

resulted in a reduction in freshwater input, which has had profound effects on the physical and 

ecological functioning of the estuary. Due to the prolonged variation in freshwater inputs, the 

estuary closed to the sea for an extended period for the first time in January 2009, and 

remained closed until July 2009. In December of the same year, the estuary enetered another 

prolonged closed phase. This alteration in the natural flow regime will most likely to result in a 

reduction in the frequency and extent of floodplain inundation, and a reduction in scouring of 

sediment in the estuary. Further threats to the estuary include increased siltation due to 

erosion, the loss and destruction of natural habitat by development and alien plant invasion, 

and deterioration in water quality caused by agricultural and residential pollution. 

This study forms part of the Cape Action Plan for the Environment (C.A.P.E.) Regional Estuarine 

Management Programme. The main aim of the programme is to develop a strategic 

conservation plan for the estuaries of the Cape Floristic Region (CFR), and to prepare detailed 

management plans for each estuary. The estuary programme is divided into three phases. The 

first phase involved the establishment of a regional conservation plan (Turpie & Clark 2007), 

the development of guidelines for estuary management plans (van Niekerk & Taljaard 2007), 

and the preparation of detailed management plans for a few selected systems. Of these, 

Anchor Environmental Consultants cc was tasked with preparing the management plan for the 

Uilkraals Estuary. These studies will then pave the way for preparation of management plans 

for the remaining systems in the region in subsequent phases of the programme. 

This document is the Situation Assessment report for the Uilkraals Estuary. It provides 

background information on the estuary including the geographic and socio-economic context, 

a description of the ecosystem functioning and biodiversity, the legal and planning context, 

threats to the system, and its conservation importance. This document will form the basis of 

the development of a vision and strategy for the management of the estuary in a participatory 

process involving stakeholders. Terms of Reference for the study are in Appendix 1. 


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2. GEOGRAPHIC AND SOCIO-ECONOMIC CONTEXT 

2.1 Location and extent of the estuary and its catchment 

The Uilkraals Estuary is situated approximately 60 km northwest of Cape Agulhas and 11 km 

east of Danger Point on the south-west coast within the cool temperate biogeographic region 

of South Africa (Whitfield 1998) (Figure 2). It is the first estuary to be found east of Danger 

Point (Heydorn & Bickerton 1982). The Uilkraals River runs southward and drains into the 

Indian Ocean 6 km southeast of Gansbaai. The total catchment area of the Uilkraals Estuary 

covers approximately 105 ha (Turpie & Clark 2007). 

Figure 2. Map of the south western tip of South Africa. The arrow indicates the relative position of the 

Uilkraals Estuary (adapted from Harrison 2004). 

Figure 3. Map showing Overberg region in which the Uilkraals Estuary is located. 


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The Uilkraals catchment lies within the Overberg District Municipality in the Western Cape 

Province and the estuary is located within the Overstrand Local Municipality (Figure 3 and 

Figure 4). The estuary enters the sea at 34˚36’23”S 19˚24’33”E when the estuary mouth is 

open (Whitfield 2000). The river is approximately 46 km in length from the mouth to the 

source of the Sondagskloof, one of its major tributaries. The junction of the Sondagskloof and 

the Perdeberg rivers forms the Uilkraals at an approximate elevation of 200 m roughly 30 km 

from the mouth. In the lower catchment the Boesmans River joins the Uilkraals approximately 

6 km from the mouth. The size of the estuary from the mouth to the the confluence of the 

Uilkraals and Boesmans is approximately 260 ha (Heydorn & Bickerton 1982). A bridge 

approximately 220 m long spans the estuary approximately 800 m from the mouth. A 

causeway approximately 120 m in length supports the eastern road access to the bridge whilst 

the remaining 100 m is spanned and supported by large concrete pylons (Heydorn & Bickerton 

1982). 

Figure 4. Overstrand Local Municipality map showing the main settlements. The Uilkraals Estuary 

(shown by the arrow) is located between Gansbaai and Pearly Beach (Source: Overstrand SDF 2009). 


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2.2 Catchment climate, vegetation and drainage 

The Uilkraals River Catchment is relatively small at 313 km 2 , is dominated by Table Mountain 

Sandstone (Heydorn & Bickerton 1982) and lies wholly within the Western Cape Province, 

which receives most precipitation during the winter rainfall season. MAR for the whole 

catchment is approximately 22 Mm 3 (van Niekerk, unpubl. data) and the average annual 

rainfall in the catchment ranges between 500 and 700 mm (Heydorn & Tinley 1980, Heydorn & 

Bickerton 1982) with peaks in June and July. The river flow is therefore high in winter with runoff 

declining in summer. At Franskraal, located at the estuary mouth, the annual average daily 

maximum temperature is 22°, with the monthly average maximum temperature ranging from 

27°C in February to 18°C in June, July and August. The annual average daily minimum 

temperature is 11°C. The settlement of Franskraal receives on average 500-600 mm annually 

with most of the rain falling in the winter months (South African Rain Atlas 2010). 

The spatial patterns in the natural vegetation within the Uilkraals River Catchment are 

determined primarily by the underlying geology and regional rainfall. The upper catchment is 

characterised by the acidic and nutrient poor Table Mountain Group (TMG) sandstones and 

quartzites, which are dominated by mountain fynbos. Lower down in the river valley, rocks of 

the Malmesbury Formation outcrop and support limestone fynbos. The mountain fynbos 

vegetation in the higher lying areas of the Uilkraals River catchment remain predominantly 

intact. The lower areas of the catchment have been altered by increased anthropogenic 

activities, mainly agriculture and alien plant invasion. Natural riparian vegetation along most 

of the Uilkraals River’s course (with the exeption of the saltmarsh alongside the estuary) has 

been replaced by invasive exotics, in particular gums, poplars, Port Jackson and rooikrans (Gale 

1998). 

Figure 5. Overstrand Local Municipality physical morphology and landscape map (Source: Overstrand 

SDF 2009). 


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The Kraaibosch dam (Figure 6) was constructed on the Uilkraals River in 1999 to supply the 

town of Gansbaai with water for domestic and industrial use and the surrounding areas with 

water for irrigation. The dam wall lies appproximately 10 km upriver from the estuary mouth 

(du Preez & Sasman 1999), covers 102 ha and can hold 5.5 x 10 6 m 3 . According to the dams 

permit conditions only winter flow is allowed to be retained and all summer flow is let through. 

Detailed flow records of river inflow, spillage, rainfall and outflow are kept on a daily basis. 

Data collected over the past 48 years shows that the average annual rainfall (Figure 7) has 

remained between 600 and 750 mm per annum. The amount of rain received over the last 10 

years is in fact comfortably above this annual average, which strongly suggests that recent 

anomalous mouth closure events are most likely attributable to the construction and operation 

of the Kraaibosch the dam, as opposed to changes in rainfall. Retaining water in the dam 

decreases riverine base flows and floods which changes the physical functioning of the estuary. 

Estuaries are not only reliant on base flow but also require flood peaks to scour them and 

maintain their dynamics, something that cannot easily be supported where in-channel storage 

dams are developed (DWAF 2004a). 

The Boesmansrivier which joins the Uilkraals approximately 6 km from the mouth also has a 

large dam upstream called the Nieuwedam. There is an unknown number of small dams and 

water abstraction points by local farmers on the river below the Nieuwedam. The total volume 

of water abstracted from these dams is not known though. The Breede Water Managament 

Area (WMA) Internal Strategic Perspective (ISP) anticipated that the Uilkraals River Catchment 

(G40M) would have a 40% increase in summer allocations out of the Kraaibosch Dam (DWAF 

2004a) indicating increasing demand, through the progressive implementation of agricultural 

development in the catchment. 

Figure 6. Kraaibosch Dam (Source: Google Earth) 


14 


Figure 7: Annual rainfall for the Uilkraals River Catchment from 1962 – 2009. 

2.3 Catchment population, land-use and economy 

Population and socio-economic status 

The total population living within the Overstrand Local Municipality, in which the Uilkraals 

River Catchment is located, was estimated at 74 546 in the 2007 StatsSA Community Survey. 

Population density was estimated at 35 people per square kilometre and total household count 

was 24 485. The majority of the population in the Overstrand Local Municipality are classified 

as Coloured (37%) and White (34%), followed by Black Africans (29%) (Local Economic 

Development 2008). The overall population of the Uilkraals River catchment (G40M) is a small 

proportion of the total for the Overstrand Local Municipality as it contains a relatively small 

urban area. Larger settlements such as Gansbaai with approximately 20 000 residents and 

Stanford with 8 000 residents are located outside of the boundaries of the Uilkraals catchment. 

The Overberg District Municipality population growth has been declining since 1995, and the 

average annual growth rate is only 3%. If the current trend of population growth continues, 

the Overberg will soon have a negative growth rate, as is already seen in the Cape Agulhas 

Local Municipality (Local Economic Development 2008). Approximately 56% of the population 

in the Overberg area is employed, with 20% of the population being unemployed (Local 

Economic Development 2008). Agriculture and trade are the economic sectors with the 

highest employment at 20.1% and 16.5%, respectively. The geographic trend in economic 

activity along the catchment is predominately agriculturally based in the middle and upper 


15 


eaches and tourism and fishing industry based near the mouth. One of the larger tourism 

developments within the catchment is the Uilenkraalsmond Holiday Resort, located at the 

estuary mouth, which includes permanent holiday cottages, caravan sites and recreational 

amenities. 

Land-use 

The catchment consists mainly of agricultural areas and an ecological corridor/area, with some 

private conservation areas and other statutory conservation areas. Development within the 

catchment includes small urbanised areas along the coast and larger areas developed for 

agricultural purposes, with agriculture, fruit farming, stock-farming, viticulture and nature 

conservation being the main land use activities. Agriculturally based industries dominate in the 

Overstrand and include wineries, fruit and fynbos cultivation (Overberg Spatial Development 

Framework 2004). The Overstrand Local Municipality lists the Uilkraals River Catchment as an 

intensive agricultural resource area (Figure 8). 

Urban development accounts for a very small proportion of the catchment land cover. The 

major towns in the area, Gansbaai and Stanford, lie adjacent to the Uilkraals catchment. The 

largest town within the catchment is Franskraal, which is located at the mouth of the estuary 

on the coast. 

Figure 8. Intensive agricultural resource areas showing the Uilkraals River Catchment as being one of 

the larger agricultural areas in the Overstrand (Source: Overstrand SDF 2009). 


16 


Economy 

Agriculture dominates much of the upper Uilkraals River Catchment, with wineries, fruit 

cultivation and fynbos cultivation being the most important contributors to this sector. 

Tourism is a major economic contributor across the catchment, through nature based 

recreation and holiday destinations. The estuary is considered a bird watching destination and 

recreational fishing remains a draw card. In addition, Pearly Beach and the Uilenkraalsmond 

Resort are big attractions to the Uilkraals catchment, where the popularity as a holiday 

destination results in a fourfold increase in the population over the holiday seasons. The 

Overstrand has had the highest positive annual Gross Domestic Product growth in the 

Overberg District since 1995 (Local Economic Development 2008). In 2008, the Gross Domestic 

Product for the Overberg District was estimated to be in the region of R4 billion, equivalent to 

approximately only 0.3% of the national GDP (Local Economic Development 2008). 


17 


3. ECOLOGICAL CHARACTERISTICS AND FUNCTIONING OF 

THE ESTUARY 

3.1 Mouth dynamics, hydrology and channel shape 

The Uilkraals Estuary has been classified as a temporarily open-closed estuary (Whitfield 2000), 

and is a mixed (in terms of salinity), blackwater system (van Niekerk unpubl. data). When 

functioning naturally, the estuary has tidal exchange and a high frequency of connection to the 

sea, similar to the Palmiet and Kleinmond estuaries, but is in a more advanced stage of 

progressive infilling and reduction of the tidal prism (Harrison et al. 1995a). The road bridge, 

which was constructed in 1973, is approximately 220 m long and crosses the river 

approximately 800 m from the mouth (Figure 9 and Figure 10). It is supported on the eastern 

side by a high embankment of rubble spanning almost two-thirds of the original high tide river 

width (Gaigher 1984). The remaining 100 m are supported by concrete pylons, effectively 

halving the width of the estuary there and concentrating the river flow against the western 

bank (Heydorn & Bickerton 1982). In 1978 a 150 m long rubble and rock embankment was 

built on the beach in front of the beach facing bungalows, forcing the estuary mouth 

eastwards, away from the caravan park (Heydorn & Bickerton 1982). However, the 

embankment was quickly eroded by wave and tidal action and a shallow, stagnant pool of 

water and a series of sand dunes formed on the beach in front of the bungalows (Figure 9). 

In the past the estuary mouth opened over a beach with a relatively flat profile and the open 

mouth status was probably maintained by strong tidal currents (Harrison 2004). Tidal currents 

play a major role in maintaining a connection with the sea in cool and warm-temperate 

estuaries (unlike subtropical estuaries, where river flow is the major factor; Cooper et al. 1999, 

Cooper 2001). Seasonal closure and migration of the estuary occurs due to strong seasonal 

variations of river flow and wave climate where limited river flow allows the formation of a 

sand bar across the estuary mouth. 


18 


Figure 9. An aerial view of the Uilkraals Estuary mouth in October 1979 (altitude of 500m). 

When functioning naturally, the river enters the sea via a meandering channel across the 

floodplain, which opens onto sand flats (Heydorn & Bickerton 1982). The road bridge crosses 

at the lower reaches of these sand flats. There are several river channels which flow across the 

sand flats upstream of the bridge (Heydorn & Bickerton 1982). The mouth was originally 

mobile and in the past could enter the sea at any point between the eastern dune and western 

part of the beach opposite the caravan park (Heydorn & Bickerton 1982). The mouth later 

became fixed by a combination of factors, including the causeway of the road bridge and the 

stabilization of both the eastern and western dunes (Heydorn & Bickerton 1982). 

Figure 10. Picture of the bridge and causeway of the Uilkraals Estuary facing downstream. 


19 


The first time in recorded history that the Uilkraals Estuary became closed for a long period of 

time was in January 2009. It re-opened six months later for a short period but closed again for 

an extended period in December 2009. Water storage in the Kraaibosch Dam, approximately 

10 km upstream from the estuary, has significantly altered the natural freshwater in-flows to 

the estuary while agricultural activities in the upper catchment have introduced an increased 

sediment load into the estuary, ultimately resulting in reduced flow over time and an increased 

likelihood of mouth closure of the estuary in low flow periods. 

The lower reaches of the estuary used to consist of several braided channels that expanded to 

a single 400 m wide channel at high tide (Harrison et al. 1995b). Water in the area below the 

bridge is now restricted to two smaller shallow channels, the larger of which ends at the beach 

in front of the huts at the caravan park (Figure 11). Before mouth closure occurred, tidal 

influence reached beyond the bridge, with the majority of the sandflats becoming inundated at 

high tide (Harrison et al. 1995b). Tidal interchange was recorded up to 3 km upstream in a 

1981 survey (Heydorn & Bickerton 1982). Currently, a very shallow braided channel runs 

across the sandflats upstream from the bridge, probably similar to former low tide conditions. 

The majority of the sandflats are now permanently exposed (Figure 12). 

Figure 11. The closed estuary mouth facing upstream (left) and the area below the bridge facing 

downstream (right, picture taken from the bridge), February 2010. 

The middle reaches of the estuary consist of a wide meandering channel across a large 

floodplain, surrounded by saltmarsh vegetation. Before the road bridge was built, the estuary 

was a marine-dominated tidal lagoon. The large volumes of tidal exchange would have rapidly 

reduced any effects of floods, when they did occur (Gaigher 1984). Factors affecting 

circulation also affect salinity by altering the volumes of salty water entering the estuary as 

well as the ratio of dilution of fresh and salt water (Clark 1977). The obstruction caused by the 

road bridge would therefore have changed the circulation and hence salinity regime of the 

estuary immensely. This would have been most critical during periods of freshwater flooding, 

by prolonging the extension time of freshwater over tidal sandbanks. This effect would have 

been most intensive in the extensive flood area on the landside of the bridge (Gaigher 1984). 


20 


Figure 12. Pictures of the exposed sandflats above the bridge, February 2010. 

Flows recorded at Kraaibosch Dam (some 10 km upstream of the estuary) are well correlated 

with rainfall in the area. While flows are largely natural in the upper reaches, there are 

substantial decreases in downstream flow during the winter months compared with natural 

condition, and increases in summer flow along parts of the river. Annual flood peaks into the 

estuary are important, but the impact of a flood also depends to some extent on the base flow, 

with greater flooding impact when the base flows are higher. The estuary currently receives an 

estimated 80% of its natural MAR (van Niekerk, unpubl. data), however, an important 

component of the natural flow (i.e. winter and summer base flows) has been modified to a 

large extent, including reductions in floods that would normally scour the system and maintain 

the opening of the estuary to the sea. 

There is little data on the sediments or on historical sedimentation processes of the Uilkraals 

Estuary. Estuaries contain a mixture of river and marine sediments, the balance of which is 

determined by the amount of water moving in and out of the estuary during a tidal cycle, 

riverine base flows and floods. The size of particles that can be transported from the 

catchment increases with amplified velocity, and larger particles are deposited before small 

particles as flow decreases. Base flows carry relatively little sediment, mostly fine silts, and this 

is deposited when freshwater flows are slowed by the pushing effect of incoming sea water. 

This process generally leads to an accumulation of fine sediments in the lower to middle 

reaches of the estuary, which results in the channel and inter-tidal areas becoming muddier 

and shallower with time. Floods carry a lot of silt from the catchment, and this is deposited 

wherever floodwaters slow down significantly, such as on the floodplain. They also scour away 

accumulated sediments from the estuary the channel and in the lower inter-tidal areas. Very 

large floods may scour the floodplain as well. The area of scouring versus deposition depends 

on the size of the flood. 


21 


3.2 Water chemistry 

The distribution of saline water in an estuary (the longitudinal salinity distribution) is of 

fundamental importance as it affects the distribution of all biota in the system due to their 

differing salinity tolerances. River inflow and sea level together determine the penetration of 

seawater into the system, thereby determining the salinity profile of the estuary. 

In 1979 and 1981 surveys showed that salinities below the bridge ranged from 35.5‰ at the 

mouth to 26‰ at the bridge. The main channel had a salinity of 20‰ 2 km from the mouth 

and 0‰ only 500 m further upstream (Heydorn & Bickerton 1982). Harrison (2004) measured 

salinities at six stations along the estuary and reported a mean value of 15.43‰ (SE ± 2.11). 

Surface water temperature was recorded as 24.5˚C to 25.5˚C at 400 m and 500 m from the 

mouth respectively in the 1979 survey (Heydorn & Bickerton 1982). At the same sampling sites 

dissolved oxygen concentrations of 9.8 mg/l and 10.8 mg/l were measured, with a higher 

measurement of 13.0 mg/l near algae at the latter (Heydorn & Bickerton 1982). Harrison 

(2004) measured a mean temperature of 17.33˚C (SE ± 0.27), a mean dissolved oxygen 

concentration of 8.49 (SE ± 0.11) mg/l and a mean turbidity of 5.33 (SE ± 0.88) NTU. Extended 

mouth closure events will affect the water chemistry of the estuary. The estuary is no longer 

flushed by the sea or freshwater as frequently as it was in the past and this could result either 

in hypersaline conditions or fresh conditions developing within the estuary, depending on the 

amount of freshwater inflows and the amount of evaporation. 

3.3 Microalgae 

Microalgae in estuaries comprise unicellular algae that live either suspended in the water 

column (termed phytoplankton) or benthically on rocks or sediments in the estuary (termed 

microphytobenthos or benthic microalgae). These microalgae (i.e. phytoplankton and 

microphytobenthos) are very important in estuarine systems as they are generally the main 

source of primary production in the estuary. 

Phytoplankton communities in estuaries are influenced by salinity, generally dominated by 

flagellates where river flow dominates and by diatoms in marine dominated areas. Diatoms 

are most common in the area of the estuary where the salinity is in the region of 10-15‰, 

often referred to as the River Estuary Interface (REI) zone. Phytoplankton biomass in an 

estuary is also generally at its maximum in this region. Biomass of phytoplankton in estuaries 

varies widely and may range from 0-210 µgChla/l (Adams et al. 1999). If nutrient 

concentrations in an estuary are high (particularly in the case of nitrogen) then phytoplankton 

biomass in the estuary is generally high too. Under extreme conditions, when nutrient levels 

are very high, certain toxic dinoflagellate species may form dense blooms known as red tides. 

Less is known about benthic microalgae (microphytobenthos) in estuaries than phytoplankton. 

Values for benthic microalgae biomass are often reported in different units which makes 

comparisons between estuaries difficult. Currently there is no available information on 

microalgae in the Uilkraals Estuary. 


22 


3.4 Vegetation 

There are four main vegetation communities associated with the Uilkraals Estuary: macroalgae, 

submerged macrophytes, reeds and sedges, and salt marsh. 

Heydorn & Bickerton (1982) recorded 13 species of semi-aquatic plants in and around the 

Uilkraals Estuary. These included Crassula glomerata, Plantago carnosa, triglochin bulbosum, 

Scirpus littoralis, Sebaea minutiflora, Sebaea albens, Spergularia marginata, Cotula eckloniana, 

Chenolea diffusa, Samolus deis and Limonium scabrum. 

Macroalgae 

Macroalgae can be indicative of water quality and nutrient enrichment. Macroalgae may be 

intertidal (intermittently exposed) or subtidal (continually submerged) and can be attached to 

hard or soft substrata or they may float (Adams et al. 1999). Opportunistic macroalgae are 

found in temporary closed estuaries like the Uilkraals as they can tolerate fluctuating salinities. 

During a survey in 1981 the filamentous algae Enteromorpha and Cladophora were recorded in 

the estuary and Ulva beds were present under the road bridge (Heydorn & Bickerton 1982). 

Enteromorpha and Cladorphora belong to the family Chlorophyta, and are often found to 

extend further into estuaries due to their salinity tolerance (Adams et al. 1999). 

Submerged macrophytes 

The high macrophyte diversity in the Uilkraals Estuary is of conservation importance. There 

are approximately 2 ha of submerged macrophytes in the estuary, which provide an important 

habitat for invertebrates and juvenile fish. Submerged macrophytes are plants rooted in both 

soft subtidal and low intertidal substrata, which are completely submersed for most states of 

the tide (Adams et al. 1999). Submerged macrophyte beds support diverse and abundant 

invertebrate and juvenile fish communities (Whitfield 1984, 1989). Primary productivity of 

submerged macrophytes is high and on par with the most productive plant habitats in marine 

and terrestrial ecosystems (Day 1981, Fredette et al. 1990). Adams et al. (1999) found in saline 

waters in the region, Zostera capensis is prevalent. Submerged macrophytes are important in 

their provision of food for epifaunal and benthic invertebrate species as well as nursery areas 

for juvenile fish through the provision of food, shelter and protection (Adams et al. 1999). 

Salt marsh 

Salt marshes in estuaries are a source of primary production and provide habitat and food for a 

variety of faunal species (Adams et al. 2006). The degree of tidal flushing is important in 

determining how much nutrients they release into the water column (Childers & Day 1990). 

An open mouth is important as this maintains the intertidal salt marsh community. Salt marsh 

plants are distributed away from the water’s edge along an inundation gradient (Figure 13). 

Intertidal salt marsh occurs between the limits of the high and low tide ranges, while supratidal 

marsh occurs above the intertidal zone and is only normally flooded during spring tide and 


23 


other associated high water levels. Floodplain marshes are normally elevated above the rest of 

the estuary, and are normally only covered with water during large flood events. 

Mucina et al. (2003) described and classified 11 salt marsh plant communities at the Uilkraals 

Estuary. Dominant species included Salicornia meyeriana, Sarcocornia perennis agg., S. 

capensis, S. decumbens, Bassia diffusa, Limonium sp. nova, Juncus kraussii subsp. kraussii, 

Sporobolus virginicus and Triglochin bulbosa. In a 1981, study the saltmarsh covered an area of 

approximately 1.3 ha or 0.6% of the studied estuarine region (Heydorn & Bickerton 1982) and 

had the highest cover (95%) of all recorded vegetation types. A more recent vegetation study 

recorded approximately 38 ha of saltmarsh, which is still the highest cover of all recorded 

vegetation types and is of high conservation importance. 

Figure 13. Picture of the upper channel and saltmarsh area facing upstream, February 2010. 

Reeds and sedges 

Reeds and sedges act as natural biological filters, they are important for bank stabilisation as 

they are rooted in soft intertidal or shallow subtidal strata (Adams et al. 1999). Reeds and 

sedges contribute to the diversity of aquatic life, particularly the avifauna (Coetzee et al. 1997). 

Terrestrial vegetation 

Parsons (1982) identified 10 main terrestrial plant communities around the Uilkraals Estuary, 

including the saltmarsh (Error! Reference source not found.). These can be consolidated into 

five plant formations visually: low shrubland (0.25-1.0 m), mid-high shrubland (1-2 m), 

woodland, herbland and grassland. In the study area (205 ha) the low shrubland was the most 

extensive (39 ha), followed by the herbland (37 ha) and woodland (32 ha). Mid-high shrubland 


24 


covered 19 ha and grassland 1.3 ha. Open sand, including the beach, made up 46 ha. Fynbos 

communities made up fairly large patches in the study area with a total cover of 56 ha or 

27.3% of the study area. Dense stands of exotic vegetation surround the estuary with the main 

invader being the rooikrans Acacia cyclops (Heydorn & Bickerton 1982). 

3.5 Invertebrates 

Invertebrates inhabiting estuaries can be divided into a number of sub-groups based on where 

they reside in the estuary. Zooplankton live mostly in the water column, benthic organisms 

live in the sediments on the bottom and sides of the estuary channel, and hyperbenthic 

organisms live just above the sediment surface. Benthic organisms are frequently further 

subdivided into intertidal (those living between the high and low water marks on the banks of 

the estuary) and subtidal groups (those living below the low water mark). Only limited 

information on some benthic and hyperbenthic species is available for the Uilkraals Estuary, 

summarised below. 

Benthic invertebrates 

During a 1955 survey, before the construction of the road bridge, a good population of 

bloodworms Arenicola loveni, sandprawns Callianassa kraussi and mudprawns Upogebia 

africana were found both up- and downstream of the foot bridge (Heydorn & Bickerton 1982, 

Gaigher 1984). In 1973 a strong, viable population of bloodworms was reported in the tidally 

exposed sandbanks of the estuary reaching at least 2 km upstream (Gaigher 1984). Three 

years later, after the erection of the road bridge and the long rubble embankment on which it 

was built, no bloodworms were found above the bridge, which is situated approximately 800 m 

from the mouth. Another survey in 1979 confirmed the extinction of the bloodworm in the 

estuary. A very small juvenile bloodworm population was found in a permanent seawater pool 

on the beach adjacent to the estuary mouth (Gaigher 1984). The associated change in the 

salinity regime of the estuary caused by the construction of the road bridge is the most likely 

cause of the loss of this species from the estuary. 

In December 1979 sandprawns and mudprawns were found up and downstream of the new 

road bridge, with sandprawns being more abundant and more widely distributed. Mudprawn 

distribution ended abruptly 100 m upstream of the bridge (Heydorn & Bickerton 1982). In 

March 1981, sandprawns were found in abundance from the mouth across the floodplain to 

where freshwater conditions prevailed. Only a few mudprawn burrows were noted (Heydorn 

& Bickerton 1982). 

Hyperbenthic invertebrates 

The crown crab Hymenosa orbiculare and the hermit crab Diogenes brevirostris were abundant 

near the road bridge in 1979, while smaller numbers of the crab Cyclograpsus punctatus were 

found in the same area. In 1981 large numbers of C. punctatus were found just above the 

bridge, as well as large numbers of the shrimp Palaemon pacificus (Heydorn & Bickerton 1982). 


25 


3.6 Fish 

Estuaries provide an extremely important habitat for fish in southern Africa. The vast majority 

of coastal habitat in southern Africa is directly exposed to the open ocean, and as such is 

subject to intensive wave action throughout the year (Field & Griffiths 1991). Estuaries in 

southern Africa are thus disproportionately important relative to other parts of the world, in 

that they constitute the bulk of the sheltered, shallow water inshore habitat in the region. 

Juveniles of many marine fish species in southern Africa have adapted to take advantage of 

this situation, and have developed the necessary adaptations to enable them to persist in 

estuaries for at least part of their life cycles. There are at least 100 species that show a clear 

association with estuaries in South Africa (Whitfield 1998). Most of these are juveniles of 

marine species that enter estuaries as juveniles, remain there for a year or more before 

returning to the marine environment as adults or sub-adults where they spawn, completing 

the cycles. Several other species also use estuaries in southern Africa, including some that are 

able to complete their entire life cycles in these systems, and a range of salt tolerant 

freshwater species and euryhaline marine species. Whitfield (1994) has developed a detailed 

classification system of estuary associated fishes in southern Africa. He recognized five major 

categories of estuary associated fish species and several subcategories (Table 1). 

Table 1. Classification of South African fish fauna according to their dependence on estuaries (Whitfield 

1994) 

Category 

I 

Ia 

Ib 

II 

IIa 

IIb 

IIc 

III 

IV 

V 

Description 

Truly estuarine species, which breed in southern African estuaries; subdivided as follows: 

Resident species which have not been recorded breeding in the freshwater or marine 

environment 

Resident species which have marine or freshwater breeding populations 

Euryhaline marine species which usually breed at sea with the juveniles showing varying 

degrees of dependence on southern African estuaries; subdivided as follows: 

Juveniles dependant of estuaries as nursery areas 

Juveniles occur mainly in estuaries, but are also found at sea 

Juveniles occur in estuaries but are more abundant at sea 

Marine species which occur in estuaries in small numbers but are not dependant on 

these systems 

Euryhaline freshwater species that can penetrate estuaries depending on salinity 

tolerance. Includes some species which may breed in both freshwater and estuarine 

systems 

Obligate catadromous species which use estuaries as transit routes between the marine 

and freshwater environments 

Fish species in categories I, II, and V as defined by Whitfield (1994) are all wholly or largely 

dependent on estuaries for their survival and are hence the most important from an estuary 

conservation perspective. These species need to receive most attention from a management 

perspective. 


26 


Because the Uilkraals Estuary is categorised as a cool-temperate open-closed system its 

icthyofaunal composition is likely to be consistent with estuaries in the same category as fish in 

estuaries respond to their environment in a consistent manner and estuaries with similar 

habitats and environmental regimes support similar species assemblages (Whitfield 1998). 

Harrison (2005) described species caught during extended field research carried out in the 

1990s, with open cool-temperate estuaries having an average of 6.8 species captured per 

estuary. The numerically dominant species caught included harder Liza richardsonii, cape 

silverside Atherina breviceps and estuarine round-herring Gilchristella aestuaria. Kob 

Argyrosomus sp., shad Pomatomus saltatrix , flathead mullet Mugil cephalus , and cape white 

catfish Galeicthys feliceps also contributed to the overall biomass (Harrison 2005). In open 

cool-temperate estuaries like the Uilkraals, Harrison (2005) found that they did not appear to 

contain any unique taxa, instead comprising of a mix of widespread and endemic species which 

prefer cooler waters (e.g. Cape silverside and harder). 

G F van Wyk recorded white steenbras Lithognathus lithognathus, mullet (Family: Mugilidae) 

and nude goby Caffrogobius nudiceps in the estuary in 1955. During a 1981 site visit the 

presence of mullet in abundance was noted as well as the presence of white steenbras and the 

Knysna sandgoby Psammagobius knysnaensis in smaller numbers (Heydorn & Bickerton 1982). 

White steenbras is a category IIa species and is dependent on estuaries as a nursery area for at 

least the first year of life (Whitfield 1994). Harrison et al. (1995b) recorded four species of fish 

in the estuary; Cape silverside, Knysna sand goby, harder, and flathead mullet. 

An ichthyological survey at the Uilkraals Estuary was conducted in 2006. Ten hauls were done 

at 10 sampling sites, covering a total sampling area of 3000 m 2 . 11 species of fishes were 

recorded (Table 2). Three of these were likely to be breeding in the Uilkraals Estuary; Cape 

silverside, nude goby, and the Knysna sand goby. One species, flathead mullet, was likely to be 

dependent on the estuary as a nursery area for at least its first year of life. Another five 

species were at least partially dependent on the estuary as a nursery area; Cape sole 

Heteromycteris capensis, groovy mullet Liza dumerilii, blackhand sole Soleo bleekeri, harder, 

and white stumpnose Rhabdosargus globiceps. 

In total, nine species (82% of the fish species recorded from the Uilkraals Estuary) can be 

regarded as either partially or completely dependent on the estuary for their survival. The 

most abundant species in terms of numbers was the Knysna sand goby, followed by harder 

(Table 2). Both species are at least partially dependant on the estuary. In terms of biomass 

sandshark contributed most to the total biomass in the system, followed by harders. However, 

sandsharks do not rely on estuaries as part of their life cycle. 


27 


Table 2. Species composition, abundance and biomass of fish in 10 seine net hauls at Uilkraals Estuary, March 

2006. 

Species Common name Number per ha kg/ha 

Atherina breviceps Silverside 176.7 48.7 

Caffrogobius nudiceps Nude goby 6.7 11 

Psammogobius knysnaensis Knysna sand goby 13284.2 700.7 

Mugil cephalus Flathead mullet 36.7 303.3 

Heteromycteris capensis Cape sole 213.3 233.3 

Liza dumerilii Groovy mullet 3.3 496.7 

Solea bleekeri Blackhand sole 6.7 33.3 

Liza richardsonii Harder 3036.7 42492 

Rhabdosargus globiceps White stumpnose 110 52.7 

Amblyrhynchotes hokenii Evil eye blassop 33.3 70.3 

Rhinobatos annulatus Sandshark, guitarfish 20 58020 

3.7 Birds 

The Uilkraals Estuary has been identified as an important area for waterbirds (Barnes 1996). 

On a national scale it is ranked 14 th in terms of waterbird abundance in a conservation priority 

analysis study (Turpie 1995). Regionally, it was ranked 11 th out of 65 coastal wetland systems 

in the south-western Cape in terms of total bird numbers supported (Ryan et al. 1988). A total 

of 48 water-associated bird species have been recorded at the Uilkraals Estuary (Table 3). Of 

these, 23 species are piscivorous, 21 are invertebrate-feeding and only four species are 

herbivorous. 

The estuary has supported large numbers of terns and migratory waders in the past (Summers 

et al. 1976, Heydorn & Bickerton 1982, Ryan et al. 1988) and has been recognised as one of the 

largest mainland tern roosts in the south-western Cape (Ryan et al. 1988). 

Only a few bird counts have been conducted on the estuary, all of which were done in the 

summer months (Table 4). Previous counts conducted between 1976 and 1981 showed bird 

abundances ranging from 4 864 to 6 755 individuals. The count conducted in 1996 showed a 

decrease of over 4 500 individuals compared to the 1981 count. This was due to much lower 

numbers of terns being recorded, also on subsequent visits to the estuary in the following few 

days. This decrease was probably caused by changes in habitat availability. Increased erosion 

and changes in sedimentation and river flow have occurred as a long-term result of the 

causeway supporting the bridge built in 1973, and the erection of a rubble embankment 

(Barnes 1996), and more recently the decreased flows due to the upstream dam. The number 

of invertebrate-feeding waders present at the estuary remained relatively stable (Table 4). 


28 


Piscivores 

Table 3. Water-associated birds recorded at Uilkraals Estuary (Summers et al. 1976; Heydorn & 

Bickerton 1982; A. Terörde, unpubl. data). 

Invertebrate feeders 

African Darter Anhinga rufa African Oystercatcher Haematopus moquini 

African Fish-eagle Haliaeetus vocifer African Sacred Ibis Threskiornis aethiopicus 

African Spoonbill Platalea alba Bar-tailed Godwit Limosa lapponica 

Black Stork Ciconia nigra Blacksmith Lapwing Vanellus armatus 

Cape Gannet Morus capensis Blackwinged Stilt Himantopus himantopus 

Cape Cormorant Phalacrocorax capensis Cape Wagtail Motacilla capensis 

Caspian Tern Sterna caspia Common Greenshank Tringa nebularia 

Common Tern Sterna hirundo Common Ringed Plover Charadrius hiaticula 

Crowned Cormorant Phalacrocorax coronatus Common Sandpiper Actitis hypoleucos 

Giant Kingfisher Megaceryle maxima Eurasian Curlew Numenius arquata 

Great Egret Casmerodius albus Curlew Sandpiper Calidris ferruginea 

Greyheaded Gull Larus cirrocephalus Grey Plover Pluvialis squatarola 

Grey Heron Ardea cinerea Kittlitz's Plover Charadrius pecuarius 

Hartlaub's Gull Larus hartlaubii Little Stint Calidris minuta 

Kelp Gull Larus dominicanus Marsh Sandpiper Tringa stagnatilis 

Little Egret Egretta garzetta Ruddy Turnstone Arenaria interpres 

Malachite Kingfisher Alcedo cristata Sanderling Calidris alba 

Osprey Pandion haliaetus Terek Sandpiper Xenus cinereus 

Pied Kingfisher Ceryle rudis Three-banded Plover Charadrius tricollaris 

Reed Cormorant Phalacrocorax africanis Whimbrel Numenius phaeopus 

Sandwich Tern Sterna sandvicensis White-fronted Plover Charadrius marginatus 

Swift Tern Sterna bergii Herbivores 

White-breasted Cormorant Phalacrocorax lucidus Common Moorhen Gallinula chloropus 

Egyptian Goose 

Red-knobbed Coot 

Yellow-billed Duck 

Alopochen aegyptiaca 

Fulica cristata 

Anas undulata 

Table 4. Summary of bird count results conducted at the Uilkraals Estuary. 

January 1976 

(Summers et al. 1976) 

January 1976 

(Summers unpublished 

data) 

December 1979 

(Heydorn & Bickerton 

1982) 

January 1981 

(Ryan et al. 1988) 

February 1996 

(Barnes 1996) 

February 2010 

(A. Terörde, unpub. 

data) 

Number of 

species 

Total 

abundance 

Wader 

abundance 

Most abundant species 

32 Not counted 774 Waders: Curlew Sandpiper (480) 

17 4864 720 Sandwich Tern (2000) 

Waders: Curlew Sandpipers 

(440) 

26 5879 584 Sandwich Tern (5000) 

Waders: Curlew Sandpiper (480) 

24 6755 880 Common Tern (4720) 


30 2180 1041 Common Tern (513) 


22 435 60 Kelp Gull (310) 

Waders: Whimbrel (17) 


29 


For this study, a count of water-associated birds was conducted in late February 2010, when 

summer migrant numbers are usually maximal. Birds were recorded from the mouth to the 

section of the estuary where the wider channel becomes a series of smaller braided channels, 

approximately 3 km from the mouth. 

Counts during this study showed a drastic decrease in bird numbers compared to previous 

years, while diversity was not affected as much (Table 4). Only 435 individuals were recorded, 

the majority of these being Kelp Gulls (310 individuals). Most birds (89%) were found in the 

sandflats above the bridge (Error! Reference source not found.). Ten species were piscivores 

nd 12 species were invertebrate-feeding waders. No herbivores were recorded. Compared to 

the study by Barnes (1996) the proportion of invertebrate-feeders, piscivores and herbivores 

was similar. Barnes (1996) recorded 15 species of piscivores, 18 species of invertebratefeeders 

and one species of herbivore (Egyptian Goose). 

The low numbers can be explained by the significant decrease in the numbers of Curlew 

Sandpipers, as well as only a small number of terns being present (32 individuals) as compared 

to previous counts (Error! Reference source not found.). Curlew Sandpiper has been recorded 

t the estuary in high numbers during every previous survey conducted (Error! Reference source 

not found.). It is an Arctic-breeding migratory species, and is found in southern Africa from 

August/November to March/April. It forages for nereid worms, snails and crustaceans mainly 

in the intertidal area of coastal lagoons and estuaries and on sheltered open shores with much 

stranded algae (Hockey et al. 2005). The estuary was closed to the sea during the study and 

had been closed for approximately two months. Therefore, the large inter-tidal feeding habitat 

which covered the entire sandflat region below and above the road bridge was lost. Most 

inter-tidal invertebrates had probably desiccated and died or migrated elsewhere. While many 

sandprawn burrows were still present, these animals are able to burrow deeper to a level of 

sufficient moisture in dry times and are often found in closed systems. They are also very 

tolerant of varying salinities (Forbes 1974). Due to their large size and the depth of their 

burrows it is unlikely that sandprawns can be utilised as prey by small invertebrate-feeding 

waders. 

Kelp Gulls were recorded roosting for the first time in high numbers at Uilkraals with 310 

individuals recorded (Table 5). Barnes (1996) recorded 67 and Ryan et al. (1988) recorded 77 

individuals. On the day of the count a strong south-easterly wind was blowing and it is possible 

that this species seeks shelter in the estuary sporadically. Similar numbers of Kelp Gulls were, 

however, still present the following two days, even after the wind had died down. The low 

numbers of terns recorded are of particular concern as this site was once a major roost for 

several tern species including the Caspian Tern, Sandwich Tern and Swift Tern, of which it 

hosted 6.8%, 2.8% and 6.6% respectively of the south-western Cape’s population (Barnes 

1996). Whimbrel has previously been recorded in high numbers at the estuary (76 and 65 

individuals) making it the second largest population in the south-western Cape after Langebaan 

Lagoon (Barnes 1996). Only 17 individuals were recorded in this study. Whimbrel are relatively 

sensitive to disturbance and higher levels of recreational use of the estuary by people may be a 

contributing factor, in addition to the loss of intertidal feeding habitat. 


30 


In addition to the changes associated with the building of the bridge and the closure of the 

mouth, disturbance would have increased with the size of the surrounding settlements and 

amount of people utilizing the adjoining caravan park and estuary for recreational purposes. 

Table 5. Results of the waterbird count (February 2010). Area 1: mouth to bridge; Area 2: bridge to 

saltmarsh (sandflats); Area 3: channel through to saltmarsh. 

Piscivores Area 1 Area 2 Area 3 TOTAL 

Cape Cormorant 1 1 

Caspian Tern 4 2 6 

Common Tern 12 12 

Grey Heron 1 1 

Hartlaub's Gull 8 8 

Kelp Gull 310 310 

Little Egret 1 11 12 

Reed Cormorant 1 1 

Sandwich Tern 1 1 

Swift Tern 13 13 

Invertebrate-feeders 

Blacksmith Lapwing 2 3 5 

Cape Wagtail 2 2 4 

Common Sandpiper 1 1 

Curlew Sandpiper 12 12 

Common Greenshank 1 1 

African Oystercatcher 4 4 

Ruff 4 4 

Sacred Ibis 2 2 

Terek Sandpiper 3 3 

Whimbrel 17 17 

White-fronted Plover 9 7 16 

Wood Sandpiper 1 1 

Total number of individuals 24 387 24 435 

Total number of species 6 15 6 22 

3.8 Current health of the estuary 

Whitfield (2000) conducted an assessment on the condition of estuaries of the entire South 

African coast. The estuaries were broadly classified as follows: 

 

 

 

 

Excellent: estuary in near pristine condition (negligible human impact) 

Good: no major negative anthropogenic influences on either the estuary or catchment 

(low impact) 

Fair: noticeable degree of ecological degradation in the catchment and/or estuary 

(moderate impact) 

Poor: major ecological degradation arising from a combination of anthropogenic 

influences (high impact) 

The Uilkraals Estuary was classified by Whitfield (2000) as being in a fair condition. A more 

recent health assessment found that the Uilkraals Estuary has an Estuarine Health Index (EHI) 


31 


score of 55 (van Niekerk, unpubl. data). The EHI assesses the degree to which the current state 

resembles the reference (i.e. natural) condition. Once the natural hydrological conditions have 

been described, specialists assess the condition of the estuary in terms of a range of 

biophysical variables. The current state is then scored for each of these variables on a scale of 

0 (no resemblance to original state) to 100 (same as natural state). The health scores and 

overall score are summarised in Table 6. Although the estuary currently receives some 80% of 

its natural MAR, an important part of the hydrology and natural functioning of the estuary has 

been removed (winter and summer base flows) which affects the mouth condition 

significantly. The similarity score given for the hydrology of system is 50% of the natural 

condition, which is lower than the percentage in natural MAR (80% of natural). This is because 

an important component of the natural flow regime has been modified to a large extent, the 

hydrodynamics and mouth condition (0% of natural condition) are severely altered. The 

reduction in flow has also had an impact on the water quality of the system, both due to the 

reduced ability to dilute pollution and due to the increase in polluted return flows as a result of 

water use for irrigation. The reduced flows may have also altered the physical habitat of the 

estuary in that the depth and profile have changed. There has been a recorded 81% 

transformation in the 1 km buffer zone of the estuary (van Niekerk, unpub. data), most likely a 

consequence of increased alien vegetation and reduced flows. 

The reduction in flows has also resulted in considerable changes to the biota of the estuary. 

Primary productivity by microalgae is thought to have increased due to the nutrient input and 

reduction in flushing of the estuary. Being a blackwater system, the Uilkraals is naturally 

oligotrophic and because the water is being retained in the estuary for an extended period of 

time, the primary productivity has increased substantially. Plants have also been significantly 

affected. Mouth closure for such extended periods can lead to a significant reduction in 

saltmarsh vegetation. Saltmarsh cannot survive inundation which is caused by the permanent 

rise of the water level in the estuary due to a closed mouth. A reduced cueing effect to 

estuarine dependent invertebrate and fish species could result in a reduction in nursery 

function, abundance and diversity of species. Birds have also been significantly affected by the 

closure of the estuary. The large intertidal feeding habitat which covered the entire sandflat 

region below and the above the causeway has been lost, resulting in a severe decrease in 

wader numbers. The estuary has also become less suitable as a tern roost. The score of 80% 

allocated to birds is most likely an over estimate and has become even lower as the estuary 

continues to remain closed off from the sea. 

Table 6. The Estuarine Health Index scores allocated to the Uilkraals Estuary (Present State) 

VARIABLE 

SCORE (% resemblance to natural condition) 

Hydrology 50 

Hydrodynamics and mouth condition 0 

Water quality 70 

Salinity 50 

Total Water Quality Score 62 

Physical habitat 70 

Habitat health score 45.5 

Microalgae 35 

Plants (macrophytes) 70 

Invertebrates 70 

Fish 75 


32 


Birds 80 

Biological health score 64 

OVERALL EHI SCORE 55 

The overall health score of 55 translates into a Present Ecological Status of a D, which is classed 

as a largely modified system (Table 7). 

Although the Present State of the Uilkraals Estuary currently falls within an Ecological Category 

D, it is likely that the estuary is on a negative trajectory of change, because of the extremely 

low base flows under the Present State. Turpie & Clark (2007) listed the Uilkraals Estuary as a 

high priority estuary in need of rehabilitation. Alien plant clearance and the removal of the 

causeway were listed as the types of requirements needed to rehabilitate the estuary. 

Increasing freshwater inflow and ensuring more natural flows into the system are also needed. 

Table 7. Relationship between Estuarine Health Score, Present Ecological Status (PES) classification, 

and how it is understood. 

EHI Score PES General description 

91 – 100 A Unmodified, natural 

76 – 90 B Largely natural with few modifications 

61 – 75 C Moderately modified 

41 – 60 D Largely modified 

21 – 40 E Highly degraded 

0 – 20 F Extremely degraded 

Implications for the estuary 

The estuary is degrading under the current flows. The main consequences of maintaining the 

Uilkraals Estuary in an Ecological Category D through these flows are considered to be as 

follows: 

1. Excessive (or nuisance) macrophyte growth during the late summer months in the 

upper reaches, particularly if nutrient inputs are not reduced, negatively impacting on 

water intake systems, recreational usage and aesthetics (i.e. ‘loss of value’). 

2. Reduced cueing effect to estuarine dependent invertebrate and fish species and 

resulting reduction in nursery function. 

3. A loss of saltmarsh through inundation or dessication if the estuary remains closed to 

the sea. 

4. A further decrease in bird numbers as the estuary becomes less suitable for waders 

and terns. Birds that require an inter-tidal feeding area are severely affected. 


33 


4. ECOSYSTEM SERVICES 

4.1 What are ecosystem services 

Ecosystems can be viewed as natural capital which contributes to economic production. They 

provide goods, services and attributes, collectively known as ecosystem services that 

contribute to human welfare (Barbier 1994): 

Goods are harvested resources, such as fish. 

Services are processes that contribute to economic production or save costs, such as water 

purification. 

Attributes relate to the structure and organisation of biodiversity, such as beauty, rarity or 

diversity, and generate less tangible values such as spiritual, educational, cultural and 

recreational value. 

The Millennium Ecosystem Assessment (2003) recently re-categorized the services obtained 

from ecosystems as follows: 

Provisioning services such as food and water; 

Regulating services such as flood and disease control; 

Cultural services such as spiritual, recreational, and cultural benefits; and 

Supporting services, such as nutrient cycling, that maintain the conditions for life on Earth. 

The first three align well with the definitions of goods, services and attributes described above, 

while the fourth underlies these and need only be considered inasmuch as changes in these 

affect the values of the first three (Turpie 2007). 

4.2 Goods and services provided by the Uilkraals Estuary 

The main types of ecosystem services that are associated with temperate South African 

estuaries are listed in Error! Reference source not found.Table 8. 

The goods and services provided by Uilkraals Estuary are described in more detail below. 


34 


Attributes 

Services 

Goods 

Table 8. Ecosystem goods, services and attributes based on definitions by Costanza et al. (1997) that 

are likely to be provided by temperate South African estuaries (Turpie 2007) 

Ecosystem Goods, 

Services & Attributes 

Description 

Importance in 

estuaries 

Food, medicines Production of fish and food plants; medicinal plants High 

Raw materials 

Production of craftwork materials, construction materials and 

fodder 

Medium 

Gas regulation Carbon sequestration, oxygen and ozone production, Low 

Climate regulation Urban heat amelioration, wind generation Low 

Erosion control and 

sediment retention 

Waste treatment 

Refugia 

Nursery areas 

Export of materials 

and nutrients 

Genetic resources 

Structure and 

composition 

Prevention of soil loss by vegetation cover, and capture of soil in 

wetlands, added agricultural (crop and grazing) output in 

wetlands/floodplains 

Breaking down of waste, detoxifying pollution; dilution and 

transport of pollutants 

Critical habitat for migratory fish and birds, important habitats for 

species 

Critical breeding habitat, 

Nurseries for marine fish 

Export of nutrients and sediments to marine ecosystems 

Medicine, products for materials science, genes for resistance to 

plant pathogens and crop pests, ornamental species 

Species diversity and habitats providing opportunities for 

recreational and cultural activities 

Low 

Medium 

High 

High 

High 

Low 

High 

4.3 Raw materials 

There is no recorded use of building materials (e.g. reeds, sand) gathered from the Uilkraals 

Estuary for subsistence of commercial purposes. The lack of subsistence use is unsurprising 

because of the population make-up and the lack of traditional dwellings in this catchment. 

4.4 Carbon sequestration 

Carbon sequestration is measured in terms of the net storage or loss of carbon that takes place 

as a result of a long-term increase or decrease in biomass. The contribution made by estuaries 

to carbon sequestration is largely unknown, and was thought unlikely to be significant apart 

from in mangrove systems. However recent studies have found estuarine wetlands are able to 

sequester carbon at ten times the rate of any other wetland ecosystem due to the high soil 

carbon content and burial due to sea level rise (Brigham et al. 2006). Therefore higher rates of 

carbon sequestration and lower methane emissions in marsh areas, such as those identified in 

the Uilkraals by Mucina et al. (2003) have the potential to be valuable carbon sinks. 

Nevertheless, the area is not extensive and the overall value is not likely to be significant in 


35 


isolation, but only inasmuch as it contributes cumulatively to this service provided by 

ecosystems in general. 

4.5 Waste treatment 

Waste treatment is likely to be an important ecological service provided by the aquatic 

ecosystems of the Uilkraals catchment, particularly in that agricultural return flows are diluted 

and assimilated by the system. The value of this function is usually estimated in terms of the 

cost savings of treating the water before it is released. However, the quantity of pollutants 

released into the system is unknown. It is important to note that the value of the system is 

only measured in terms of the amount assimilated by the system. This capacity could be 

reduced under certain circumstances, resulting in decreased water quality downstream and 

exacerbating the negative impacts on downstream users that would already be caused by 

increased pollution loads due to agricultural expansion. 

In order to effectively quantify the value of the waste treatment services water quality 

assessments would have to identify any periods of elevated loads, which would signify when 

the Uilkraals system was not able to assimilate and dilute agricultural return flows, which have 

the capacity to deliver of organic pollutants into the estuary. 

The capacity to assimilate pollutants could also be reduced under certain circumstances, 

resulting in decreased water quality downstream and exacerbating the negative impacts on 

downstream users that would already be caused by increased pollution loads due to 

agricultural expansion. 

4.6 Export of materials and nutrients 

The export of sediments and nutrients to the marine zone is an important function of some 

river systems. For example, the prawn fisheries of KwaZulu-Natal depend on such exports 

(DWAF 2004b). However, this function is far more important on the east coast, which is 

relatively nutrient-poor, than on the west coast, where the outputs of estuaries do not 

compete with the nutrients supplied by the Atlantic upwelling systems (Turpie & Clark 2007). 

It is unlikely that the export of materials and nutrients is important in this system because its 

low mean annual runoff (MAR). 

4.7 Refugia areas and nursery value 

Refugia areas are areas that help to maintain populations in a broader area. For example, 

wetlands within relatively arid areas may play an important seasonal role in the maintenance 

of wild herbivores that are utilised in tourism operations well beyond the wetland. This is 

probably not important in the study area apart from for fish. In the rivers, some of the smaller 

tributaries have become important as refuge areas for endemic fish, although their ability to 


36 


epopulate the rest of the river system is low at present. In the estuary, some inshore marine 

fish populations may utilise the estuary as a warmer refuge during upwelling events (Lamberth 

2003). The extent of this function in its contribution to marine populations is unknown. 

Estuaries are typically shallow and sheltered habitats that provide a refuge from the action of 

waves that are characteristic of the South African coastline, making them ideal nursery 

habitats for juvenile fish species, many of which are of commercial importance (Wallace et al. 

1984). While estuaries are widely accepted as being among the most biologically productive 

ecosystems on earth (Kennish 2002), estuaries in the region where the Uilkraals is located are 

fed by oligotrophic (nutrient‐poor) rivers, and are thus not particularly productive. 

There are about 431 000 recreational fishers and well over 21 000 commercial fishers active in 

the inshore marine environment in South Africa. Commercial net fisheries (beach seine and gill 

net) on the south coast are likely to be the fisheries that benefit most from the Uilkraals 

Estuary. The commercial line fishery, recreational shore angling and recreational boat angling 

fisheries could also benefit to a small extent. 

Nursery areas are breeding habitat for populations that reside elsewhere. Estuaries provide 

nursery areas and habitat for numerous species of fishes which are exploited by recreational 

and commercial harvesting in the inshore marine environment. Different species are 

dependent on estuaries to different degrees for stages of their development and growth. 

Freshwater flow and the frequency and duration of estuary mouth openings are major factors 

affecting estuarine biota (Turpie & Clark 2007), and particularly the juveniles of marine 

organisms that use them as nursery grounds (Whitfield 1994, Strydom et al. 2003) either 

directly through habitat availability, or indirectly through their impact on estuarine 

productivity (Gillanders & Kingsford 2002). Factors that make estuaries suitable nursery areas 

are increased food, higher temperature, turbid waters and lower salinities, all of which can be 

changed by the variation in freshwater input (GiIlanders & Kingsford 2002, Turpie & Clark 

2007). The nursery function of the Uilkraals Estuary is considered to be relatively important, in 

that some marine species caught in the surrounding marine fisheries are dependent on 

estuaries as nursery areas. With high macrophyte diversity and a large area of submerged 

macrophytes within the estuary, nursery areas and refugia are important. However, the 

nursery areas may have been reduced or possibly eliminated as a result of the changes in 

functioning and mouth dynamics brought about by the upstream dams. 

As per the ichthyological survey carried out in 2006, three of the species found within the 

Uilkraals Estuary breed in the estuary, one species is completely dependent on the estuary for 

the first year of its life and five species are partially dependent on the estuary. The nursery 

value is derived from the amount of fish caught which fall under I, III and IV in terms of their 

dependence on estuaries (Table 1). Of particular importance in calculating the value is 

Category II species for which management of estuaries plays a crucial role in inshore fisheries. 

Turpie & Clark (2007) estimated the total nursery value of all the estuaries within South Africa 

from the Orange River to Kosi Bay to be in the order of R773 million per annum, ranging from 

R900 to R167 million per estuary. The majority of estuaries were estimated to have a nursery 

value in the range of R100 000 to R10 million per annum. The Uilkraals Estuary theoretically 

falls within this category (Turpie & Clark 2007), but it is unlikely that this value is realised now 

due to the closure of the estuary to the sea for such an extended period of time, and the 

reduction in freshwater flow. 


37 


4.8 Genetic resources 

Genetic resources are valuable in many systems, but probably least valuable in freshwater and 

estuarine systems, where most species are extremely widespread. There are also few species 

that have widespread commercial potential (e.g. for agriculture or horticulture). Nevertheless, 

there are endemic species, and there is a possibility that these may become useful. The 

Uilkraals, because of its high macrophyte abundance, is one of the more interesting systems 

within the area in terms of diversity. However, it is not possible to determine this value. 

4.9 Tourism and recreational value 

The Overstrand coastline, between Rooiels and Pearly Beach which includes the Uilkraals 

catchment has become an increasingly popular tourist destination for South Africans and 

overseas tourists. Much of the appeal lies in the natural features of the area, particularly the 

coastline which provides opportunities for peaceful getaways or adventure holidays involving a 

variety of aquatic and non-aquatic outdoor activities. The area is surrounded by hills in the 

form of the western Franskraalberge, the central Koudeberge and range of limestone hills 

which merge into the coastal plains. In the scale of the Western Cape mountain ranges these 

are a minor attraction (van der Merwe 2008), but do contribute positively to the aesthetic 

attraction of the region. In addition the shifting sand dunes and limestone hills have high 

species endemism. There are a number of protected areas in the vicinity of the Uilkraals 

catchment including the Uilkraalsmond Nature Reserve, Pearly Beach, Groot Hagelkraal Nature 

Reserve and Quoin Point Nature Reserve. 

Tourism is a major economic driver in the Overstrand and its popularity as a holiday and 

recreational destination is on the increase. During the peak holiday seasons, the population 

can increase four fold. As with many estuaries in South Africa, there is an urban settlement 

around the mouth of the Uilkraals Estuary. The Uilenkraalsmond Holiday Resort is located 

directly at the mouth of the estuary and is a very popular holiday resort, generally being full 

during all major holiday periods (Figure 14). The holiday resort covers a large area having both 

cottages and a caravan park with camping facilities. At R550 per night in self catering 

accommodation during the peak season and R400 a night out of season, it is expected that the 

resort generates a relatively substantial amount, which can be ultimately attributed to the 

estuary. There are a couple of upmarket bed and breakfast facilities located in the Franskraal 

village. The main attractions of the estuary are for fishing, birdwatching, and relaxation. The 

Uilkraalsmond area is considered to be under increasing development pressure, with the 

proposed rural development in the area (van de Merwe 2008). Tourism is also an important 

industry in the areas in the vicinity of the Uilkraals Estuary, with a range of adventure, ecotourism 

and consumptive (fishing) activities available to visitors. 

The Uilkraals River is considered an asset amongst the five rivers listed within the Strandveld 

area, with the coastal features at the mouth of the Uilkraals Estuary listed as important 

because of the tourism value that they hold. T he area adjacent to the mouth is varied with the 

western section forming the rocky outstretches linking to Gansbaai and the eastern section 


38 


comprised of smooth fine grained sandy beaches which continue on to Pearly Beach. The 

Uilkraals catchment is also important as a Fynbos biodiversity hotspot, containing important 

strands of remnant undisturbed fynbos. A number of places have reported the occurrence of 

red data species, in addition a number of flower harvesting and processing centres are located 

in the catchment, for example Concordia and Niewedam (van der Merwe 2008). 

Figure 14. Uilkraals Estuary (which is now closed to the sea) with the Uilenkraalsmond Holiday Resort 

situated at the mouth (inside red box). Source: Google Earth. 

Recreational use of estuaries is significant in South Africa, with an estimated total of 67 000 

recreational anglers and 5700 cast netters (Turpie & Clark 2007). Although this activity is 

relatively small in the Uilkraals Estuary area and on the coast, recreational angling (mainly 

shore angling) is carried out by many of the locals and visitors to the area. The bulk of the 

Uilkraals Estuary linefish catch is made within 500 m of the mouth. The total fishing effort for 

the Uilkraals Estuary is 2.1 tonnes, which is considerably less when compared to the Klein (80 

tonnes), the Bot (70 tonnes) and the Heuningnes (10 tonnes; Lamberth & Turpie 2003). 

The economic value of the recreational fishery can be considered in terms of the expenditure 

on fishing by recreational fishers (i.e. the income to subsidiary industries such as 

accommodation and fuel). While the commercial and traditional fisheries are forms of 

generating cash or subsistence income, and are largely valued in terms of the market value of 

their catches, the value of recreational angling does not lie mainly in the market value of the 

fish caught. Recreational anglers value the sport and experience, and expend considerable 

sums on this activity, largely irrespective of their catch returns (McGrath et al. 1997). The 

value attributed to this fishery is mostly in terms of gains to subsidiary industries that benefit 

from angler expenditure (McGrath et al. 1997). 


39 


5. LEGISLATION AND MANAGEMENT ISSUES 

5.1 The main threats and opportunities to be considered 

There are a number of factors that threaten the future health of the Uilkraals Estuary and 

hence its biodiversity and capacity to deliver ecosystem services. The main threats to the 

system or areas of potential conflict are as follows: 

1. Water quantity and quality 

a. reduction in freshwater inflows due to water storage in the catchment 

(Kraaibosch Dam), and a continuing increase in the demand for water 

b. increasing nutrient enrichment due to agriculture in the catchment 

c. Loss of important habitat area such as saltmarsh through inundation caused 

by increasing water levels in the estuary as the mouth remains closed. 

2. Exploitation of living resources 

a. potential for future overexploitation by recreational fishers 

3. Land-use and associated disturbance 

a. potential for residential/resort development around the estuary leading to 

change in sense of place and existence value, increased human disturbance 

of biota, and damage or loss of estuarine habitat 

In addition to meeting the existing legislation governing the above activities, opportunities to 

protect the health and value of the system over the medium to long term include: 

1. The establishment of terrestrial and estuarine protected areas, and 

2. Implementation of rehabilitation measures. 

All of the above issues are discussed below in the context of the prevailing policies and 

legislation. 

5.2 General policy and legislative background 

This section provides an overview of legislation and policy applicable to management of 

estuaries in South Africa and specifically to the Uilkraals Estuary. More details on the 

legislative framework for estuary management including international and regional treaties 

and obligations, national policies and laws, and provincial and local policies and legislation is 

provided in Taljaard (2007). 

The South African Constitution is the supreme law of the land, and provides the legal 

framework for legislation regulating environmental management in general. Section 24 of the 

Constitution states that: 

"Everyone has the right: 


40 


• to an environment that is not harmful to their health or well-being; and 

• to have the environment protected, for the benefit of present and future generations 

through reasonable legislative and other measures that – 

• prevent pollution and ecological degradation; 

• promote conservation; and 

• secure ecologically sustainable development and use of natural resources while 

promoting justifiable economic and social development. 

This lays the basis for environmental law in South Africa (Breen & McKenzie 2001) and is a very 

important justification for the wise use of estuarine biodiversity. 

Because they are not freshwater, terrestrial or marine, estuaries have tended to be neglected 

in past legislation. However, the fact that estuaries contain freshwater, terrestrial and marine 

components, and are heavily influenced by activities in a much broader catchment and 

adjacent marine area, means that they are affected by a large number of policies and laws. 

The situation has improved with newer policies and legislation, but there is still no specific 

provision for Estuarine Protected Areas. 

South African policy and law as pertaining to estuaries has been summarised in detail 

elsewhere (Smith & Cullinan 2000, van Niekerk & Taljaard 2002). A brief summary of the most 

relevant policies is given here (Table 9 and Table 10). Policy and legislation which affects 

estuaries directly can be roughly divided into that affecting (a) water quality and quantity, (b) 

land use and infrastructure development, and (c) living resources within estuaries (Van Niekerk 

& Taljaard 2002, Taljaard 2007). 

Estuary management falls mainly under two national government departments: the 

Department of Water Affairs and Forestry, responsible for water resources, and the 

Department of Environmental Affairs and Tourism (DEAT), responsible for everything else, e.g. 

land use, living resources. Environmental management in most instances is devolved to 

provincial level through whichever provincial department is responsible for environmental 

matters. Management and conservation of marine living resources is an exception in this 

respect, in that this is retained as a national competency, responsibility residing with the 

Branch Marine & Coastal Management (MCM) of DEAT. In instances where provincial or local 

legislation are in conflict with national legislation, national legislation prevails. At a local 

(municipality) level, municipal councils pass municipal by-laws, which in turn, cannot conflict 

with provincial and national laws (Breen & McKenzie 2001). 

The Western Cape Government has also released a Coastal Management Programme which 

includes a suite of goals, objectives and strategies designed to achieve sustainable coastal 

development in the Western Cape. These are closely aligned with the National Coastal 

Management Programme and are organised within five themes: 

Theme A: Governance and Capacity Building 

Theme B: Our National Asset 

Theme C: Coastal Planning and Development 

Theme D: Natural Resource Management 

Theme E: Pollution Control and Waste Management 

A number of goals within each of these themes are of relevance to the management of the 

Uilkraals Estuary (Table 11). 


41 


Land use & 

management 

Water quality 

& quantity 

Table 9. 

Summary of national policies which affect water quality and quantity in estuaries in general, landing use, development and resource use in the estuarine environment. 

White Paper (= Policy) Bill or Act (= Law) Lead 

Agent 

White Paper on National 

Water Policy for SA (1997) 

White Paper on Integrated 

Pollution and Waste 

Management for South Africa 

(2000) 

Implications 

National Water Act 36 of 1998 DWEA Defines the environmental reserve in terms of quantity and quality of water; provides for 

national, catchment and local management of water 

Marine Pollution (Control and 

Civil Liability) Act (1981) 

National Environmental 

Management: Integrated 

Coastal Management Act no 24 

of 2008 

Seashore Act 

(1935) as amended 

DOT/ 

DWEA 

DWEA 

DEADP 

Provides for the protection of the marine environment from pollution by oil and other harmful 

substances, the prevention and combating of such pollution, and the determination of liability in 

certain respects for loss or damage caused by the discharge of oil from ships, tankers and 

offshore installations. 

Provides for the control of dumping at sea and pollution in the coastal zone (including estuaries). 

The leasing of the sea shore for the purposes of construction on the sea-shore or in the sea. 

Environmental Conservation Act 

(1989) 

Most of the provisions of this Act have been repealed by NEMA, apart from the regulation on 

Sensitive Coastal Areas. 

National Heritage Resources Act 

(1999) 

DWEA 

Provides for managements of national heritage resources (including landscapes and natural 

features of cultural significance, and for participation of communities in the identification, 

conservation and management of cultural resources 

White Paper for Sustainable 

Coastal Development in 

South Africa (2000) 


Management: Integrated 

Coastal Management Act no 24 

of 2008 

DWEA 

Provides for integrated coastal and estuarine management in South Africa, and sustainable 

development of the coastal zone, defines rights and duties in relation to coastal areas; includes a 

National Estuarine Management Protocol for South Africa, and requires that estuarine 

management plans be developed and implemented for all estuaries 

White Paper on Spatial 

Planning and Land-use 

Management (2001) 

Local Government: Municipal 

Systems Act (2000) 

DPLG 

Requires each local authority to adopt a single, inclusive plan for the development of the 

municipality intended to encompass and harmonise planning over a range of sectors such as 

water, transport, land use and environmental management. 


42 


Use of living resources 

& MPAs 

Protected 

areas 

White Paper (= Policy) Bill or Act (= Law) Lead 

Agent 

White Paper: Mineral and 

Mining Policy for South Africa 

(1998) 

White Paper on the 

Conservation and Sustainable 

Use of South Africa’s 

Biological Diversity (1998) 

Marine Fisheries Policy for 

South Africa (1997) 

Mineral and Petroleum 

Resources Development Act 

(2002) 


Management: Protected Areas 

Act (2003) 

World Heritage Convention Act 

(1999) 


Management: Biodiversity Act 

(2004) 

Marine Living Resources Act 

(1998) 

DME 

DWEA 

DWEA 

DWEA 

DWEA 

Implications 

Deals with environmental protection and management of mining impacts, including sand and 

coastal mining. 

Provides for the protection and conservation of ecologically viable areas representative of South 

Africa’s biological diversity and its natural landscapes and seascapes; and for establishment of a 

national register of national, provincial and local protected areas, describes the different types of 

protected areas that can be declared which may also apply to estuaries. 

Provides for the incorporation of the World Heritage Convention into South African Law, and for 

the recognition and establishment of World Heritage Sites in South Africa 

Provide for the conservation of biological diversity, and regulates sustainable use of biological 

resources 

Regulates living resource use within marine and estuarine areas, mainly through licensing; 

provides for establishment of Marine Protected Areas 


43 


Table 10. 

Provincial and local government legislation applicable to the Uilkraals Estuary 

Act/Ordinance Lead Agent Implications 

Municipal Ordinance (Cape) (1974) DEADP Grants local authorities in the province of the Western Cape the power ‘to drain storm water into any natural water 

course’. 

Western Cape Nature Conservation Laws 

Act No. 15 of 1998 

Land Use Planning Ordinance (1985) as 

amended 

WCNCB 

DEADP 

Provides for the establishment of the Western Cape Nature Conservation Board. 

Most planning applications received by the provincial department are in terms of this Act including applications for 

departure, rezoning or subdivision and appeals against planning decisions taken by a municipality 

Western Cape Planning and Development Act DEADP Provides guidelines for the future spatial development in province of Western Cape 

(1999) 

Nature Conservation Ordinance (1974) WCNCB Provides for the establishment of provincial, local and private nature reserves and the protection of indigenous species of 

flora and fauna. Protected and endangered species of flora and fauna are listed in schedules to the ordinance. It is 

administered by the Western Cape Nature Conservation Board (WCNCB) and grants certain powers to the WCNCB. 


44 


Table 11. 

Goals and strategies in the Western Cape Integrated Coastal Management Programme with particular relevance to management of the Uilkraals Estuary. 

Goal # Goal Strategies 

Goal B3: 

Goal C1: 

Goal C3: 

Goal C4: 

Goal C5: 

Goal D1 

Goal D2: 

To preserve, promote or protect archaeological, historical and 

cultural resources and activities of the coast 

To promote the diversity, vitality and long term viability of coastal 

economies and activities, giving preference to those that are 

distinctly coastal or dependent on a coastal location 

To maintain an appropriate balance between built, rural and 

wilderness coastal areas in the Western Cape 

To design and manage coastal settlements to be in harmony with the 

aesthetic, environmental and cultural attributes of the Western Cape 

Coast 

To plan and manage coastal development so as to avoid increasing 

the incidence and severity of natural hazards and to avoid exposure 

of people, property and economic activities to significant risk from 

dynamic coastal processes 

To maintain the diversity, health and productivity of coastal and 

marine processes and ecosystems 

To establish and effectively manage a system of coastal protected 

areas 

B3.1.1: Implementation of section 38 of the National Heritage Resources Act 

B3.1.2: Encouragement of heritage conservation planning 

B3.1.6: Termination of inappropriate uses of places, illegal activities 

C1.7.1: Diversify tourism opportunities 

C1.7.3: Build capacity of communities to initiate and effectively participate in sustainable 

tourism ventures 

C1.7.4: Identify and address the limits imposed by natural and manmade environments 

when planning tourism (and other) initiatives 

C3.4.2: Ensure the protection and conservation of natural/wilderness areas 

C4.1.1: Determine adequate setback and buffer zones along the coast 

C4.1.2: Control the sitting of infrastructure in the coastal zone 

C4.1.3: Restrict non-coastal related land uses from being located in the coastal zone 

C4.1.4: Encourage appropriate forms of coastal settlement and building 

C4.1.5: Formulate design guidelines for all buildings and structures in the coastal zone 

C4.2.1: Develop regulations to restrict the alteration of landforms and vegetation cover in 

dynamic coastal zones 

C4.2.3: Manage pedestrian and vehicular access in coastal environments 

C5.1.1 Protect and maintain dynamic coastal features that act as a buffer against natural 

coastal processes and hazards 

C5.2.1: Incorporate appropriate preventative and adaptive measures into all planning and 

management policies, plans and decision-making processes to account for projected 

changes in climate, particularly increases in sea level 

D1.2.1 Identify and protect unique sensitive environments and habitats in the coastal and 

marine zones 

D2.1.3: Ensure proper management of protected areas that caters for ecological and 

human use requirements 

Goal D3: To ensure that the use of renewable resources and associated user D3.1.2: Adopt holistic rather than single species management approaches 


45 


Goal # Goal Strategies 

practices do not compromise the regenerative capacity of coastal 

ecosystems 

D3.1.3: Set harvest levels that correspond to the regenerative capacity of coastal 

resources 

D3.1.5: Develop adequate strategies for monitoring and compliance 

D3.1.6: Promote participation of all stakeholders in management 

Goal D5: 

Goal E1: 

Goal E2: 

To rehabilitate damaged or degraded coastal ecosystems and 

habitats 

To implement pollution control and waste-management measures in 

order to prevent, minimize and strictly control harmful discharges 

into coastal ecosystems 

To manage polluting activities to ensure that they have minimal 

adverse impact on the health of coastal communities, and on coastal 

ecosystems and their ability to support beneficial human uses 

D5.1.1: Identification of significantly degraded coastal areas and ecosystems and 

development of rehabilitation management plans 

D5.2.1: Put in place procedures to enforce rehabilitation of degraded coastal areas by 

those responsible 

E1.2.3: Inclusion of pollution and waste management into land-use planning 

E2.1.7: Reduce pollution entering rivers and estuaries by promoting catchment 

management 


46 


5.3 Water quantity and quality requirements 

Legislative context 

Water quality and quantity are mainly controlled from the terrestrial side under the National 

Water Act 36 of 1998, under DWEA (Table 9). Legislation being developed under the White 

Paper on Integrated Pollution and Waste Management for SA (2000) will also have a bearing on 

river systems. The risk of marine pollution is addressed by the Combating Pollution of the Sea 

by Oil Act 6 of 1981, under DEAT. This discussion focuses on National Water Act and the 

Integrated Coastal Management Act as being the most pertinent to the development of the 

Uilkraals Estuary Management Plan. 

The White Paper on National Water Policy for SA (1997) promotes efficiency, equity and 

sustainability in the use of water resources through its slogan “some, for all, forever”. The 

policy explicitly recognises the environment as a legitimate user of water and makes provision 

to protect the environment from overexploitation of water resources. The National Water Act 

36 of 1998 (NWA) provides the legal framework for this policy. The NWA makes provision for a 

water “Reserve” which provides the quantity and quality of water flow required in aquatic 

ecosystems required to meet basic human needs and to protect the natural functioning of a 

water resource. The latter portion of the reserve is known as the environmental Reserve. 

The classification process 

The extent to which an estuary’s functioning is catered for is determined by the designated 

“class” (= future state of health) of that estuary, with some estuaries being assigned a low class 

to allow maximal water provision and others being assigned a high class in order to meet 

conservation needs. The decision as to the designated class of the estuary is thus a critical one. 

In future, this will take place using a classification process that has recently been devised by 

DWAF and is being gazetted. This process will entail consideration of the trade-offs in value 

generated by allocating water (or pollution rights) to off-stream users (e.g. irrigation 

agriculture), flow-reducing activities (e.g. plantation forestry) and polluters (e.g. municipalities, 

farmers) versus allocating water to the environment for the provision of ecosystem services 

(e.g. fishing, tourism). The Catchment Management Agencies will in future probably play the 

key role in this decision –making process, but until these agencies are operational, decisions 

are being made with the aid of water situation assessments known as Internal Strategic 

Perspectives (ISPs) that were developed as an interim aid. 

The reserve determination process 

In the absence of a gazetted classification process, the environmental Reserve is currently 

determined on the basis of recommendations emanating from a reserve determination study 

using the Resource Directed Measures methodology in conjunction with considerations of the 

demand for water in the catchment (the classification process described above will effectively 

standardise the way this is done). In the case of the Uilkraals River System, a Reserve 

Determination Study has not been undertaken and there is no preliminary assessment of the 

freshwater requirements for individual components of the estuary. 


47 


5.4 Exploitation of living marine resources 


The exploitation of marine living resources in South Africa (which includes those in estuaries) is 

governed by the Marine Fisheries Policy for South Africa (1997) and the Marine Living 

Resources Act (1998). Objectives of the policy are as follows: 

 

 

 

 

 

to achieve optimum utilisation and ecologically sustainable development of marine living 

resources; 

to conserve marine living resources for present and future generations, to use marine 

living resources; 

to achieve economic growth, human resource development, capacity building within 

fisheries and mariculture branches, employment creation and a sound ecological balance 

consistent with the development objectives of national governments; 

to protect the ecosystem as a whole, including species which area not targeted for 

exploitation; and 

to preserve marine biodiversity. 

The Marine Living Resources Act (1998) defines the species that can be exploited, and 

protection measures for those species, such as closed areas, closed seasons and size and bag 

limits. Various types of resource-use permit systems are also defined under this act. 

Issues surrounding recreational fishing 

Compared to other estuaries along the southwest and east coasts, the Uilkraals Estuary is 

currently utilised by a relatively low number of recreational fishers. This situation could 

change in the future depending on how development in the area proceeds. 

Due to the large number of participants, and associated expenditure (tackle, bait, 

accommodation, food, travel costs), recreational fisheries have been shown to contribute 

significantly to regional economies (Mann et al. 2002, Lamberth & Turpie 2003, Pradervand et 

al. 2003). It has been shown that the demand for recreational angling is largely driven by a 

desire for relaxation and that the quantity of fish caught does not negatively affect the 

expenditure by recreational anglers (McGrath et al. 1997). Increased tourism and real estate 

development along the banks of the Uilkraals Estuary could lead to increases in recreational 

fishing effort. 

5.5 Land use and management of estuary margins 


Land use management and control of development in the coastal zone is mostly the 

responsibility of the provincial government and local authorities (municipalities), and is 

administered through the Local Government: Municipal Systems Act (2000), the National 

Environmental Management: Integrated Coastal Management Act (2009), the Seashore Act 

(1935), the National Environmental Management Act (2003) (NEMA) and associated EIA 

regulations. 


48 


Development planning has been rather ad hoc in the past, but has now been formalised under 

the Municipal Systems Act, which requires that all municipalities (i.e. Metros, District 

Municipalities and Local Municipalities) have to produce Integrated Development Plans (IDPs). 

As the IDP is a legislative requirement it has a legal status and supercedes all other plans that 

guide development at local government level. The IDP process is one of the key tools for local 

governments to cope with their developmental roles and responsibilities. It is the principal 

strategic planning instrument which guides and informs all planning, budgeting, management 

and decision-making in a municipality for a five-year period. IDPs are also supposed to guide 

the activities of other spheres of government, corporate service providers, NGOs and the 

private sector within the municipal area. Because of the participatory process it takes 

approximately 6 – 9 months to complete an IDP. The IDP is updated every five years. 

Every municipality is required to produce an indicative plan, called a Spatial Development 

Framework (SDF), showing desired patterns of land use, directions of growth, urban edges, 

special development areas and conservation-worthy areas. It must also produce a scheme, 

called a Land use Management System (LUMS)’ recording the land use and development rights 

and restrictions applicable to each erf in the municipality. The plan should be flexible enough 

to accommodate changing priorities, and the scheme has to conform to the plan. The plan 

(SDF) is a guide to development, and the scheme (LUMS) is binding. 

The National Environmental Management: Integrated Coastal Management Act No. 24 of 

2008 (ICMA), which came into force in December 2009, seeks to: 

 

 

 

 

 

 

promote the conservation of the coastal environment, and maintain the natural 

attributes of coastal landscapes and seascapes, and to ensure that development 

and the use of natural resources within the coastal zone is socially and 

economically justifiable and ecologically sustainable; 

define rights and duties in relation to coastal areas; 

determine the responsibilities of organs of state in relation to coastal areas; 

prohibit incineration at sea; 

control dumping at sea, pollution in the coastal zone, inappropriate development 

of the coastal environment and other adverse effects on the coastal 

environment; and 

give effect to South Africa’s international obligations in relation to coastal 

matters 

The ICMA defines the coastal zone as: 

“The area comprising coastal public property, the coastal protection zone, coastal access 

land and coastal protected areas, the seashore, coastal waters and the exclusive economic 

zone and includes any aspect of the environment on, in under and above such area”. 

All land below the high water mark, coastal waters and natural resources up to the boundary 

of the exclusive economic zone are considered coastal public property (s.7) that is held in trust 

by the state on behalf of the citizens of the country (s.11) 1 . The state is required by ICMA to 

take “whatever reasonable legislative and other measures it considers necessary to conserve 

and protect coastal public property for the benefit of present and future generations” (s.12). 

1 Section 11, which deals with the ownership of coastal public property, is scheduled to come into force at 

a later date. 


49 


In terms of ICMA, all land within one kilometre of the high water mark zoned for agricultural or 

undetermined use and not part of a lawfully established township at the time at which the Act 

came into force, and all other land within 100 metres of the high-water mark will be 

incorporated within a “coastal protection zone” (s.16). The purpose of coastal protection zone 

is to protect ecological integrity, natural character and the economic, social and aesthetic value 

of the land and sea below the high water mark and to maintain the natural functioning of the 

littoral active zone (s.17). Authorisation for construction of any structures within this zone 

may only be issued in terms of the NEMA EIA regulations provided the structure in question is 

inconsistent with the purpose for which the coastal protection zone was established, is likely to 

cause irreversible or long-lasting adverse effects to any aspect of the coastal environment that 

cannot satisfactorily be mitigated nor is likely to be significantly damaged or prejudiced by 

dynamic coastal processes. Provincial MEC’s are required to establish or coastal set-back lines 

so to protect the coastal public property, private property and public safety; protect the 

coastal protection zone; preserve the aesthetic values of the coastal zone; or for any other 

purpose consistent with the objectives of ICMA. The building, erection, alteration or extension 

of structures will be prohibited seaward of the coastal set back line. 

All municipalities in the country are required to facilitate public access to the seashore through 

the designation of coastal access land. 

Certain sections of the coast may be designated as “special management areas” in terms of 

the Act for the purpose of conserving, protecting or enhancing coastal ecosystems and 

biodiversity in the area and for facilitating the management of coastal resources by a local 

community. 

The Act requires that all estuaries in the country be managed in a co-ordinated and efficient 

manner and in accordance with a national estuarine management protocol. 

Minister and provincial MECs are also empowered to remove any structure on or within the 

coastal zone deemed to be having an adverse effect on the coastal environment by virtue of its 

existence or because it has been erected, constructed or upgraded in contravention of this Act 

or any other law. 

The national government (DEAT), all coastal provinces and coastal municipalities are also all 

required to prepare coastal management programmes for managing the coastal zone within 

their areas of jurisdiction. These coastal management programmes are required to set out a 

vision, objectives, priorities and strategies for achieving objectives, norms and standard for 

management of the coastal zone, and a framework for co-operative governance that identifies 

the responsibilities of different organs of state in respect of the management of the coast. 

Coastal management programmes are required to be consistent with other planning 

documents (e.g. IDP and SDF documents) and vice versa. Coastal municipalities are also 

empowered to pass bylaws in terms of the Act for the purpose of administrating and enforcing 

their coastal management programmes. 

Agricultural activities in and around the Uilkraals Estuary, include livestock grazing, fruit 

farming, viticulture and wild flower farming and are all subject to the Conservation of 

Agricultural Resources Act (1983) which gives the Minister of Agriculture, Forestry and 

Fisheries the power to prescribe control measures to achieve the objectives of the Act (viz. the 

maintenance of the production potential of land, by the combating and prevention of erosion 


50 


and weakening or destruction of the water sources (including estuaries), and by the protection 

of the vegetation and the combating of weeds and invader plants). 

Development within the coastal zone is also to some extent controlled through National 

Environmental Management Act No.107 0f 1998 (NEMA) and associated EIA regulations. A 

range of listed activities are included in the annexures to the regulations for which either a 

Basic or full EIA are required. In the event that a developer wishes to undertake a project 

involving any of the listed activities, the developer is required to appoint an independent EIA 

practitioner to conduct a Basic Environmental Assessment (in the case of the former) or initiate 

a scoping exercise in the case of the latter). Following completion of such an assessment, an 

application must then be made to the relevant authority (Western Cape Department of 

Environmental Affairs & Development Planning or DEAT in the case of the Kogelberg area) for 

approval of the project. The application will be considered by the MEC/Minister and his/her 

staff and a Record of Decision issued indicating that the development may either proceed 

under certain conditions, must be subject to a more detailed assessment (i.e. full EIA), or may 

not proceed at all. The Record of Decision (ROD) issued by the authority (DEADP) may be 

appealed by the applicant (or anyone opposed to the development) which could result in the 

ROD being upheld, additional conditions being imposed on the development, or the ROD being 

overturned. Such an appeal must be lodged within 30 days of the ROD being published, using 

the appropriate forms. Further details on the EIA process, application and appeal forms are 

available on the Cape>Gateway website 

(www.capegateway.gov.za/eng/directories/services/11537/10199). 

NEMA requires that activities identified by the Minister may not commence without an 

environmental authorisation in terms of section 24. When applying for an environmental 

authorisation an environmental impact assessment must be undertaken to assess potential 

impacts on the environment, socio-economic condition and cultural heritage, the results of 

which must be reported to the authority charged with authorizing, permitting or otherwise 

allowing the implementation of an activity (in this case DEA&DP). 

Regulations were promulgated in 2006 which regulate procedures and criteria for EIA and list 

activities which are subject to basic assessment reports and scoping assessment and 

environmental assessment reports. Applications for the following activities, listed in GN No. R. 

386, are subject to a basic assessment as provided in regulations 22 – 26 of the Environmental 

Impact Assessment Regulations (GN No. R. 385): 

1. The construction of facilities or infrastructure, including associated structures and 

infrastructure, for - 

(a) any purpose in the one in ten year flood line of a river or stream, or within 32 

metres from the bank of a river or stream where the flood line is unknown, excluding 

purposes associated with existing residential use, but including – 

(i) canals; (ii) channels; (iii) bridges; (iv) dams; and (v) weirs; 

(b) marinas and the launching of watercraft on inland freshwater systems; 

2. Construction or earth moving activities in the sea or within 100 metres inland of the highwater 

mark of the sea, in respect of – 

(a) facilities for the storage of material and the maintenance of vessels; 

(b) fixed or floating jetties and slipways; 

(c) tidal pools; 

(d) embankments; 


51 


(e) stabilising walls; 

(f) buildings; or 

(g) infrastructure. 

3. The prevention of the free movement of sand, including erosion and accretion, by means of 

planting vegetation, placing synthetic material on dunes and exposed sand surfaces within a 

distance of 100 metres inland of the high water mark of the sea. 

4. The dredging, excavation, infilling; removal or moving of soil, sand or rock exceeding 5 

cubic metres from a river, tidal lagoon, tidal river, lake, in-stream dam, floodplain or wetland. 

5. The removal or damaging of indigenous vegetation of more than 10 square metres within a 

distance of 100 metres inland of the high water mark of the sea. 

6. The excavation, moving, removal, depositing or compacting of soil, sand, rock or rubble 

covering an area exceeding 10 square metres in the sea or within a distance of 100 metres 

inland of the high-water mark of the sea. 

Applications for the following activities, listed in GN No. R. 387, are subject to scoping and 

environmental impact assessment as provided in regulations 27 – 36 of the Environmental 

Impact Assessment Regulations (GN No. R. 385): 

9. The construction or earth moving activities in the sea or within 100 metres inland of the 

high-water mark of the sea, excluding an activity listed in item 2 of Government Notive No.R. 

386 of 2006 but including construction or earth moving activities in respect of- 

(a) facilities associated with the arrival and departure of vessels and the handling of 

cargo; 

(b) piers; 

(c) inter- and sub-tidal structures for entrapment of sand; 

(d) breakwater structures; 

(e) rock revetments and other stabilising structures; 

(f) coastal marines; 

(g) coastal harbours; 

(h) structures for draining parts of the sea; 

(i) tunnels; or 

(j) underwater channels 

Section 3.1 of the Sea-shore Act No.21 of 1935 requires that a lease be obtained from the 

relevant administering authority before commencing construction activities on the sea-shore 

(the land between the low water and high water marks) or in the sea. This administrative 

function was delegated to the coastal provinces (Proclamation R27 in GG 16346 of 7 April 

1995). Since this delegation of powers the Sea-shore Act has been repealed in its entirety by 

ICMA, except for those sections that were assigned to provinces. Thus the administrative 

power of the various provincial authorities to let the sea-shore still prevails despite the Seashore 

Act being repealed. 

In the Western Cape this administrative function was transferred by section 2 of the Western 

Cape Nature Conservation Laws Act No. 15 of 1998 to the Western Cape Nature Conservation 

Board (Cape Nature). Cape Nature, a public entity responsible for nature conservation in the 

Western Cape, is the competent authority to which applications for leases of the sea-shore are 

addressed. 

During the evaluation of applications Cape Nature is required to: 


52 


take into consideration whether the letting is in the interests of the general public and will 

not seriously affect the general public’s enjoyment of the sea and sea-shore; 

consult with a local authority if the land adjoining the portion of the sea-shore is under the 

jurisdiction of that local authority; 

publish a notice in the Provincial Gazette, before granting a lease, to inform the public of the 

proposal and the inspection date and provide opportunity for objections. According to 

Section 3(6), any objection submitted in response to such advertisements must be 

considered by Cape Nature prior to entering into a lease agreement or issuing of a permit. 

Development planning pertaining to the Uilkraals Estuary 

The Spatial Development Framework for the Western Cape Province is pitched at a very broad 

level, encapsulated in the vision “a home for all in the Western Cape”. It offers very little 

material guidance of specific relevance to the management of the Uilkraals Estuary, except to 

say that estuaries are unique ecosystems under serious threat both directly from human 

activities such as overexploitation, waste discharges, and through activities in the catchment. 

The IDP and SDF for the Overberg District Municipality and the SDF for the Overstrand Local 

Municipality contain much more of direct relevance to the management of the Uilkraals Estuary. The 

Overberg District Municipality IDP has recently been updated for 2010-2011, the local SDF document 

is recent from 2009 and the District level SDF, although written in 2004, is still relevant. Excerpts from 

the existing documents have been collated in Table 12 (Overberg District Municipality IDP), Table 13 

(Overberg District Municipality SDF) and 


53 


Table 14 (Overstrand Local Municipality Bioregional Plan SDF). 

Table 12. 

The vision, mission and objectives of the Overberg District Municipality as outlined in the 

2010-2011 IDP document. 

Vision Mission Objectives 

To bridge the 

racial socioeconomic 

divide 

and to create 

sustainable 

livelihoods and 

thriving 

communities 

within the 

Overberg 

District 

To preserve and 

further develop the 

district through the 

preservation of the 

region’s rural 

character, the 

promotion and 

sustainable utilisation 

of the region’s 

diversity, and to 

ensure sustainability 

and development of 

human and natural 

resources to the 

benefit and wealth of 

all inhabitants and for 

the promotion of 

economic growth 

and development 

• To support the development of a diversified, resilient 

and sustainable district economy in order to promote 

economic growth, build skills, create jobs and eradicate 

poverty 

• To ensure that all people are located within integral 

human settlements and have access to social services 

and security 

• To facilitate the improvement and expansion of the 

provision bulk and basic services to all the people 

• To ensure the health and safety of communities through 

the prevention and management of risks 

• To facilitate sustainable and efficient land use and 

planning frameworks 

• To facilitate the necessary institutional transformation 

and financial sustainability of the ODM in order to make 

it a truly developmental municipality 

Both the local and district SDF documents highlight the importance of conservation areas and 

the need for protection of biodiversity and ecosystem functioning. Both documents recognise 

the potential for natural resources (agriculture, forestry, fishing etc.) to support economic 

development as well as the notion that natural attributes of the area (including the estuary) 

have a regional value for opportunities e.g. ecotourism. Restoration and rehabilitation of 

natural areas are listed as key strategies and both SDF documents emphasise the strategy of 

invasive alien plant clearance. The Uilkraals River Catchment has extensive areas of alien 

vegetation that run along the course of the river and estuary within the riparian zone. The 

Overstrand Local Municipality SDF document states restrictions on future development i.e. 

restrictions on development below the 1:100 flood line and in sensitive areas, such as 

wetlands, floodplains and riparian systems. Development around the estuary is relatively low, 

but with increasing tourism to the area development will surely increase and consequently put 

pressure to cross the existing urban edge. Both SDF documents state that the natural 

functioning and natural processes of ecosystems must be protected and the effective 

management of catchments must be ensured. The district level SDF also focuses on estuaries 

directly and states that the long term protection of estuaries must be ensured and that areas 

around the estuary mouth must be protected from any development impacts. The Uilkraals 

Estuary is at present not functioning naturally and the natural processes associated with the 

estuary have been disrupted. The management of the catchment is therefore not effective as 

the rivers natural flow patterns have not been regulated successfully. 

The Overstrand Local Municipality SDF compiled a spatial planning and management concept 

(Figure 15) which further underpins the municipality’s approach to the integrated spatial 

management of land use and economic development within its jurisdictional area. The main 


54 


principles involve identifying an overarching spatial development pattern within a clear 

hierarchy of nodes and settlements. The hierarchy of the development patterns being clearly 

defined based on empirical determined growth potentials, the principles of comparative 

advantage and the prerequisite of sustainable development. The growth of urban nodes and 

rural settlements should be strictly contained within well-defined boundaries and growth 

should be managed so as to ensure that development pressures are, wherever possible, 

directed and absorbed within the defined urban areas. Appropriate densification specific to 

each area must be encouraged to limit unwanted sprawl into the rural vicinity. The diversity, 

health and productivity of natural eco-systems, throughout the rural, urban and agricultural 

areas should be maintained through an interlinked web of natural spaces and the protection of 

important sensitive habitats. Prime and unique agricultural areas must be protected from nonsoil 

based land use activities. The diversification of rural and industrial based development 

opportunities, based on location and comparative resource advantages must be promoted in 

selected areas to stimulate economic growth and employment of the rural population. 

Figure 15. The Spatial Management Concept for the Overstrand Local Municipality, showing core urban 

areas, rural settlements and settlement hierarchy (Source: Overstrand SDF 2009). 


55 


Table 13. 

Overberg District Spatial Development Framework (SDF) 

Component Strategy with spatial implications Strategy without spatial implications 

Protected 

Areas 

Nature 

Estuaries, Lakes and 

Natural Water Bodies 

Natural resources 

• Rocks 

• Soils 

• Minerals 

1. Expand statutory conservation 

status to at least 12% of the ODM; 

2. Establish protected nature areas in 

conservation worthy habitats; 

3. Consolidate statutory and de facto 

nature areas to form extensive 

continuous tracts of conservation 

land; 

4. Link important statutory 

conservation areas; 

5. Establish conservancies on suitable 

privately-owned land. 

1. Ensure long-term protection of 

estuaries, lakes, and natural water 

bodies. 

2. Ensure effective management and 

conservation of catchments. 

1. Regulate the exploitation and 

utilisation of all geological and 

mineral resources to limit 

ecological and aesthetic damage; 

2. Regulate miming in accordance 

with the SPCs; 

3. Limit loss of agricultural soil to a 

‘tolerable’ level (10 

tonnes/ha/annum) 

1. Conserve the ecological and social integrity of natural areas and provide a broad spectrum of compatible outdoor 

recreational opportunities; 

2. Improve efficiency of conservation authorities and state departments; 

3. Rationalise departmental functions; 

4. Centralise the management of all statutory conservation areas; 

5. Determine and regulate carrying capacity in accordance with ecological requirements; 

6. Restore degraded sites or conservation areas; 

7. Institute plans and programmes for managing statutory conservation areas; 

8. Ensure constructive public involvement in environmental conservation; 

9. Foster public acceptance of ownership and responsibility for specific conservation areas; 

10. Collect public funds for management of specific conservation areas; 

11. Ensure educated public interest and involvement in nature conservation and in the management of conservation 

areas. 

1. Protect all estuaries and river mouths from developmental impact; 

2. Improvement of the current knowledge base. 

1. Impose and monitor soil conservation programmes in all sectors; 

2. Conserve biodiversity and the life-supporting natural processes and functions of ecosystems; 

3. Rehabilitate soil erosion sites; 

4. Institute programmes for managing indigenous and alien vegetation; 

5. Control all alien plant infestations; 

6. Apply appropriate land-use guidelines in accordance with SPCs; 

7. Determine and monitor erosion sites; 

8. Apply appropriate management practises; 

9. Control construction of new dams. 

10. Regulate all mining in accordance with the applicable legislation; 

11. Ensure effective rehabilitation of mining sites; 

12. Control all forms of mining. 


56 



Water 

1. Ensure appropriate management of 

all catchment areas within the 

municipal area. 

2. Manage mountain catchment areas 

in accordance with existing 

management systems. 

3. Ensure conservation of all the 

water resources of the region. 

1. Establish viable sustainable new irrigation schemes to facilitate sustainable agricultural development; 

2. Undertake thorough hydrogeological studies; 

3. Determine ecological effects of proposed and existing schemes; 

4. Institute effective public participation of all IAPs when considering major developments; 

5. Maintain ecological processes inherent to the catchment systems; 

6. Protect sensitive areas such as ‘sponge areas’; 

7. Include the private sector in catchment management; 

8. Consolidate legislation; 

9. Coordinate catchment management at all levels; 

10. Regulate unnatural disturbance regimes in accordance with ecological requirements; 

11. Control all alien plant infestations in river courses; 

12. Control all forms of pollution in catchment areas; 

13. Regulate modification of river beds and natural flow patterns; 

14. Regulate future development in accordance with the availability of water; 

15. Promote effective agricultural practises; 

16. Conserve water through ‘effective water management’; 

17. Institute measures to repair leaking storage dams or to utilise leaking from these dams; 

18. Ensure equitable payment of levies by all water users; 

19. Ensure equitable access of water to all rightful users; 

20. Allocate water in accordance with the available water resource; 

21. Implement strategies to overcome capacity problems experienced by Overberg Water; 

22. Ensure minimum stream flow requirements of the natural environment; 

23. Ensure sufficient and sustainable water provision to all rightful users; 

24. Ensure water quality of a high standard; 

25. Sustainable utilisation of alternative water resources such as ground water; 

26. Limit flood damage to infrastructure and developed land to ‘acceptable levels’: 

27. Regulate the construction of obstructions in rivers and streams; 

28. Conserve riparian and riverine vegetation; 

29. Prevent or mitigate the negative effects if essential bulk water releases from dams; 

30. Institute proactive measures to prevent/mitigate negative effects of natural floods. 


57 



Flora 1. Conserve the diversity of plants 

that are indigenous to the region 

at species, population and 

community level. 

2. Conserve sensitive plant habitats 

as indicated by CAPE, SKEP and 

STEP. 

3. Establish an additional biosphere 

reserve in the region. 

4. Establish a system of protected 

nature areas. 

5. Establish bioregional 

conservancies. 

6. Promote the establishment of 

Special Management Areas. 

Fauna 

1. Consolidate and extend the natural 

habitats of the indigenous animal 

communities of the region. 

2. Consolidate the natural habitats of 

endangered animal species. 

1. Conserve the diversity of plants that are indigenous to the municipal area at species, population and community level; 

2. Identify and conserve all known sensitive habitats; 

3. Maintain or simulate natural disturbance regimes; 

4. Control all infestations and alien plants; 

5. Institute effective environmental education; 

6. Regulate flower shows; 

7. Maintain minimum viable populations of rare endemic plant species; 

8. Prevent local extinction of rare endemic species; 

9. Mitigate the negative effects of disasters; 

10. Protect rare and endemic plant species; 

11. Promote the sustainable utilisation of indigenous flora for financial benefit; 

12. Promote the value of indigenous flora; 

13. Regulate harvesting of natural plant products; 

14. Regulate grazing in accordance with agricultural stocking rates; 

15. Promote the sustainable utilisation of forests for the benefits of local economy and communities; 

16. Regulate afforestation; 

17. Rehabilitate afforested areas in catchment areas; 

18. Determine feasibility of alternative farming options. 

1. Conserve the natural habitats of the indigenous animals of the region; 

2. Conserve all sensitive animal habitats; 

3. Control all alien animal species; 

4. Locate sensitive or threatened habitats; 

5. Conserve the diversity of animals that are indigenous to the ODM at all levels; 

6. Re-introduce species that historically occurred in the region; 

7. Activate and/or support natural population dynamics to recreate historical species diversity; 

8. Simulate or replicate natural disturbance regimes; 

9. Regulate artificial distribution of endemic species; 

10. Regulate the utilisation of renewable animal resources; 

11. Institute contingency measures to mitigate negative impact disasters; 

12. Maintain minimum viable populations of rare and endemic animal species; 

13. Maintain population dynamics of rare endemic species; 


58 



Cultural Resources 

Rural development 

1. Provide all the infrastructure and 

services that are essential for 

improving the quality of life of 

people living in rural areas of the 

region. 

2. Institute effective roads upgrading 

and maintenance. 

Urban development 1. Provide the necessary 

infrastructure and services needed 

to improve the quality of life of 

communities in urban areas of the 

14. Conserve all indigenous animal species; 

15. Promote sustainable utilisation of indigenous and exotic fauna for financial benefit; 

16. Regulate utilisation of wild animal resources 

17. Involve communities in conservation and sustainable use of indigenous fauna; 

18. Utilise renewable resources; 

19. Promote and apply principles of sustainable resource utilisation; 

20. Promote sustainable game and abalone farming. 

1. Conserve representative samples of the historical buildings and structures in the study area; 

2. Conserve all archaeological resources on state and private land for present and future generations; 

3. Conserve all ‘intangible’ cultural resources, such as oral history, language, place names, social activities, and human 

habits; 

4. Conserve all underwater cultural resources throughout the coastal zone of the ODM. 

1. Ensure application of place-specific planning and design guidelines for rural development. 

2. Co-ordinate institutional functions to prevent duplication and facilitate effective use of available financial and other 

resources. 

3. Establish partnerships between government and private sector for funding upgrading of infrastructure and services. 

4. Develop and upgrade infrastructure and services to accommodate community needs. 

5. Safeguard the ecological, social and aesthetic qualities of the natural environment through appropriate environmental 

planning; 

6. Increase environmental awareness at all levels of society; 

7. Ensure appropriate environmental control in all rural development; 

8. Monitor all aspects and influences of development to identify and rectify negative impacts; 

9. Impose similar environmental and legislative requirements on all development; 

10. Limit negative impacts on the ecological, social and aesthetic environment to acceptable levels; 

11. Regulate the construction of power lines, roads and other infrastructure; 

12. Regulate golf estate developments in accordance with place-specific planning; 

13. Regulate waste disposal to prevent pollution of the natural environment and natural resources. 

1. Develop the necessary infrastructure and facilities to accommodate the aspirations, needs and pressures of present 

and future industries and dependent communities; 

2. Institute place-specific planning as fundamental requirement of all urban development to safeguard the cultural, social 

and aesthetic al qualities of the urban environment; 


59 



Economic sectors 

• Tourism 

• Agriculture 

• Forestry 

• Fishing 

• Manufacturing 

Community 

development 

region. 

1. Advance the development of 

tourism infrastructure in keeping 

with location-specific architectural, 

environmental and aesthetic 

requirements; 

2. Ensure effective management of 

agriculture throughout the ODM; 

3. Provide sustainable opportunities 

for small and emerging farmers. 

4. Ensure maintenance if commercial 

forestry as a primary economic 

sector in the ODM; 

5. Ensure the proper planning and 

development of industrial areas 

and manufacturing facilities 

required for adequate 

manufacturing of products 

3. Ensure effective management of municipal functions and facets to ensure equitable and affordable services and 

amenities, and a safe and aesthetically pleasing urban environment for the resident tax-paying communities; 

4. Limit negative impacts of urban development to pre-determined acceptable levels; 

5. Develop necessary infrastructure and facilities required to improve transportation in, and aesthetic qualities in urban 

areas; 

6. Regulate waste disposal to prevent pollution of the natural environment and natural resources; 

7. Provide essential infrastructure required to improve electricity provision. 

1. Ensure the conservation and preservation of the area’s character and natural aesthetics by imparting information to 

tourists; 

2. Ensure cost-effective management of tourism at all levels; 

3. Promote community-based and driven industry with inherent direct and indirect benefits for the communities; 

4. Promote the development of sustainable agricultural enterprises in the ODM; 

5. Combine professional management skills with human, mechanical and financial resources in order to ensure 

sustainable agriculture; 

6. Undertake appropriate detailed planning as a standard practise on farms; 

7. Diversify agricultural enterprises; 

8. Make the status of natural resources and the environment determinants for sustainable agriculture; 

9. Regulate and utilise the potential rezoning of agricultural land to promote comparative economic advantages of the 

ODM; 

10. Ensure development and maintenance of harbours and facilities required for viable fishing; 

11. Promote sustainable utilisation of indigenous and exotic fish species for financial benefit; 

12. Ensure the protection of marine resources; 

13. Explore the feasibility of alternative fishing and aquaculture enterprises as community empowerment initiatives; 

14. Ensure the sustainable use and protection of natural resources; 

15. Ensure constructive public involvement in manufacturing activities; 

16. Explore alternative and emerging technologies. 

1. Ensure sustainable development of all the people of the ODM; 

2. Create a safe, healthy and aesthetically acceptable social environment for all communities; 

3. Create a sustainable growing economic environment for all the communities of the ODM; 

4. Create equal opportunities for professional education and training in order to ensure sustainable human resources and 

access to available job opportunities 


60 



Effective District 

Management 

5. Regulate land reform in accordance with the Land Reform programme; 

6. Establish constructive involvement of communities in local government; 

7. Promote constructive involvement of communities in the rehabilitation of degraded areas and the involvement of 

landowners and the general public in sustainable land management and socio-economic development planning; 

8. Promote sustainable community empowerment through the efficient use of public resources. 

1. Ensure effective cooperation and coordination between the various levels of government; 

2. Manage the district in accordance with a place-specific and community-based management approach that is 

supportive and supplementary to the existing municipal governance process; 

3. Establish mechanisms and procedures to enable the ODM to fulfil its constitutional obligations pertaining to socioeconomic 

development throughout its area of jurisdiction. 


61 


Table 14. Overstrand Local Municipality Bioregional Plan, taken from the Spatial Development Framework (SDF) 2009. 

Component Description Policies 

Conservation I 

Represents areas of highest conservation 

status. This includes unique areas, areas 

which are irreplaceable in terms of 

achieving national conservation 

objectives, and/or areas which provide 

valuable ecosystem services in terms of, 

particularly, maintaining water production 

and/or quality, protecting soils, regulating 

floods, buffering coastal areas, etc. Land is 

in Public ownership. 

Conservation II Represents areas of the highest 

conservation status. Includes unique 

areas, relatively large areas, clustered 

and/or discrete areas which are 

irreplaceable in terms of achieving 

national biodiversity conservation 

objectives, and/or areas which provide 

valuable ecosystem services in terms of, 

particularly, maintaining water production 

and/or quality, protecting soils, regulating 

floods, buffering coastal areas, etc. Land is 

in Public ownership. 

1. Protect transformation of areas of Critically Endangered or Endangered natural vegetation. 

2. Protect the biodiversity and ecosystem functioning of the Conservation Area. 

3. Protect the distinctive landscape character of the area. 

4. Promote sound management of natural resources. 

5. Permit use of natural resources if and only if such use would be sustainable and would not jeopardise biodiversity 

conservation. 

6. Safeguard areas identified as important for key ecological and evolutionary processes. 

7. Eradicate alien invasive species. 

8. Promote the restoration of degraded and disturbed areas. 

9. Promote awareness of the significance and uniqueness of natural vegetation and ecosystems of the area amongst 

the local landowners and communities, visitors and tourists. 

1. Prohibit transformation of areas of Critically Endangered or Endangered natural vegetation. 

2. Protect the biodiversity and ecosystem functioning through sound management and eradication of alien invasive 

plants. 


4. Promote sound management of natural resources. 

5. Permit use of natural resources if and only if such use would be sustainable and would not jeopardise biodiversity 

conservation. 

6. Safeguard areas identified as important for key ecological and evolutionary processes. 

7. Eradicate alien invasive species. 

8. Prohibit subdivision of agricultural land. 

9. Promote rehabilitation of degraded or disturbed areas. 




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Conservation- 

Agriculture Buffer 

Core Agriculture 

Rural, modified landscapes of relatively 

high value in terms of achieving national 

objectives for biodiversity conservation, 

particularly in terms of maintaining 

ecological and evolutionary processes 

outside of the conservation areas, and 

safeguarding valuable ecosystem services 

such as production of harvestable goods, 

water production and/or protection of 

water quality, protecting soils, regulating 

floods, buffering coastal areas etc. In 

addition it contributes to the protection of 

cultural assets (specifically landscapes of 

visual or heritage value). 

Rural landscapes of largely transformed 

areas which may contain remnants of 

Critically Endangered or Endangered 

natural vegetation, which may have value 

in terms of food production, maintaining 

ecosystem services, and protecting 

heritage assets. Land is in private 

ownership. 

1. Prohibit transformation of those areas of buffer which are situated in key ecological/evolutionary process areas, in 

sensitive and/or dynamic environments, and/or which provide connectivity between protected or threatened 

ecosystems within the municipal boundary to similar systems beyond the municipal boundary. 

2. Allow only limited transformation of the conservation agriculture buffer area for agricultural or other development 

purposes, ensuring that transformation would not jeopardise either the ecosystem status of habitat in this area or 

important ecological process areas. 

3. Allow low impact activities only. 

4. Protect the biodiversity, connectivity and ecosystem functioning in the conservation areas through sound and 

supportive management practises in the buffer area, as prescribed by CapeNature. 


6. Promote sustainable use and sound management of natural resources and of the agricultural land in the buffer area. 

7. Prospecting or mining to be granted in certain conditions. 

8. Promote efficient use of water resources and safeguard those ecosystems that regulate water yield and quality 

(wetlands, riparian systems, floodplains). 

9. Support the diversification of the agricultural sector in terms of agri-tourism and value adding in the sub-region. 

Promote research into the sustainable use and harvesting of indigenous natural resources. 

10. Prohibit the subdivision of land currently used for agriculture, unless such sub division is for the purposes of 

incorporating additional land into the conservation areas. 

11. Promote restoration (preferably), or rehabilitation of degraded or disturbed areas. 

12. Promote eradication of alien species. 



1. Prohibit transformation of areas of Critically Endangered or Endangered natural vegetation. 

2. Safeguard areas identified as important for key ecological and evolutionary processes 


4. Promote sustainable use and sound management of agricultural land and natural resources, employing the 

principles of ‘Landcare’ as endorsed by the Department of Agriculture. 

5. Promote eradication of invasive alien vegetation. 

6. Protect sensitive areas such as wetlands, drainage lines, and riparian areas. 

7. Promote efficient use of water resources. 

8. Promote restoration or rehabilitation of degraded or disturbed areas. 


63 



9. Support diversification of the agricultural sector in terms of tourism and value adding in the sub-region. 

10. Retain areas of high primary production potential for agricultural use. 

11. Discourage the subdivision of land currently used for agriculture, except where it is consistent with the 

requirements as stipulated by Act 70 of 1970, and the guidelines for the sustainable sizes of farms required for 

various types of produce, as determined by the Department of Agriculture. 

12. Permit mining and mineral extraction where it would not results in unacceptable negative impacts on local 

ecosystems or ecosystem services, and/or local communities. 



Agricultural 

Settlements 

Modified rural landscapes which contain 

small, low-density, nodal settlements. 

Intensive small scale agriculture 

dominates the land use. There areas are 

transitional between urban and partly 

transformed natural landscapes. 

1. Promote sustainable use and sound management of agricultural land. 

2. Safeguard areas identified as important for key ecological and evolutionary processes 

3. Zoning permission for commercial uses outside the designated Agricultural Settlements should not be granted. 

4. Applications for future development should comply with the restrictions on the development below the 1:100 year 

flood line. 

5. Development within the Agricultural Settlements should avoid or minimise negative impacts on ecosystems and 

should promote efficient use of resources. 

6. Adverse impacts of the Agricultural Settlements on adjacent areas should be minimised. 


64 



Core Urban 

Intensive settlement areas of relatively 

high density within the study area, able to 

obtain and support a range of services and 

opportunities. These areas have defined 

edge and contain range of land use 

activities. 

1. Zoning permission for commercial uses outside the designated commercial areas should not be granted. 

2. Safeguard areas identified as important for key ecologically and evolutionary processes. 

3. Applications for future development should comply with the restrictions on the development below the 1:100 year 

flood line. 

4. Development within the Core Urban Area should avoid or minimise negative impacts on ecosystems and should 

promote efficient use of resources. 

5. Adverse impacts of the Core Urban Area on adjacent areas should be minimised. 


65 


Issues of surrounding land use and development 

There is currently relatively little development and use of the margins of the Uilkraals Estuary. 

Nevertheless, there is increasing demand for development along the Overstrand coast, and 

applications for development around the estuary margins are likely to increase in the future. 

Increased development will lead to the degradation and loss of estuary habitats, and will bring 

about the increased use of the estuary for recreational purposes. This, in turn, could create 

problems of disturbance and pollution if inadequately managed. Recreational use of the 

estuary is discussed further below. 

Not only does future development pose a threat to the estuary habitats and fauna, it also 

threatens the cultural heritage of the area in terms of changing the nature of the historicallyinteresting 

areas along the estuary and coastline. 

5.6 Non-consumptive recreational use 

Legislation 

There is no legislation at present that specifically controls non-consumptive recreational use of 

the estuary. There are indirect means by which this can and has been achieved. 

Regulations were promulgated in 2001 that provided for a general prohibition on the 

recreational use of vehicles in the coastal zone and regulates the licensing and control of 

recreational boat launching sites and provided procedures for approving the use of vehicles in 

the coastal zone [1] under specific circumstances (Regulations No. 13399, Government Gazette 

No. 22960, promulgated under Section 44 of the NEMA). These regulations effectively banned 

any person from using a vehicle in the coastal zone unless the use is a listed permissible use, is 

authorised in terms of a permit or is authorised in terms of an exemption. 

Zonation of recreational uses of estuaries has only been applied within protected areas 

(national parks or nature reserves). 

Management issues 

The Uilkraals Estuary is used recreationally for fishing, birdwatching and photography, and is 

currently appreciated for its unspoilt, wilderness feel and the quaint settlements on its 

margins. Although these uses have not been quantified in any way, they pose little threat to 

the estuary at present. 

[1] The “coastal zone” is described by the ORV Regulations as: “the area adjacent to the sea 

characterised by coastal landforms, and includes beaches, dunes, estuaries, coastal lakes, 

coastal wetlands, land submerged by the waters of the sea, or of any estuary, coastal lake or 

coastal wetland, boat-launching sites, proclaimed harbours and recreational use areas” 


66 


Other recreational activities are of more concern. There is reportedly also some use of the 

estuary margins by quad bikers that may be causing environmental damage. Aircraft such as 

gyrocopters and microlights have been observed flying low over the estuary, and causing 

disturbance of birds. 

With increasing development pressure in the area, disturbance of wildlife is likely to increase. 

Appropriate management measures such as protected areas and zonation could be developed 

to guard against impacts associated with increased use. 

5.7 Potential for protected area status 


The White Paper on the Conservation and Sustainable Use of South Africa’s Biological Diversity 

(1998) recognises the importance of estuaries and commits the government to a number of 

strategies to protect wetlands in general, such as facilitating the development of appropriate 

legislation to secure their conservation, promoting the establishment of a National System of 

Protected Wetlands, preventing inappropriate activities and development around wetlands, 

finding ways to recognise wetlands in planning and decision-making, determining the impact of 

fishers and developing guidelines for managing them. 

Marine reserves were previously proclaimed under the Sea Fishery Act 12 of 1988 or under the 

National Parks Act 57 of 1976. Now all marine reserves have been re-proclaimed under the 

Marine Living Resources Act. However, this only affords protection up to the high tide mark. 

Estuaries can also be protected within regular protected areas (see below), though the latter 

do not have jurisdiction over the use of estuarine living resources. Estuaries may also be 

protected within World Heritage Sites under the World Heritage Convention Act 49 of 1999. 

The General Policy in terms of the Environment Conservation Act – Terrestrial and Marine 

protected areas (1994) categorises protected areas into 7 categories (based on IUCN and one 

additional category). It prescribes the management objectives and criteria for selecting and 

managing each category. The policy suggests that estuaries, fish, spawning areas and 

seascapes should generally be treated as Category IV – Habitat and wildlife management areas, 

regardless of who owns those resources. In reality, estuaries could fall into any category. 

Those such as Kosi could be classified as Category V – Protected land/seascapes, while others 

could be classified as Category VI - Sustainable Use Areas. Each estuary should be classified on 

the basis of the management objectives of the estuary (Smith & Cullinan 2000). 

The Biodiversity Act (2004) provides for the conservation of biological diversity. It requires 

identification of important landscapes, ecosystems, ecological process and species for 

biodiversity conservation, and promotes monitoring of these. It also provides for the 

proclamation of protected areas, recognising South Africa’s obligations to international 

conventions. The Protected Areas Act (2003) provides for the declaration and management of 

protected areas, and can also provide for co-operative governance, the sustainable utilisation 

of protected areas that preserves their ecological character, and the participation of local 

communities in the management of protected areas, where appropriate. A consultation and 

public participation process is outlined in the Act. It also contains the requirement that marine 

and terrestrial protected areas with common boundaries must be managed as an integrated 


67 


protected area by a single management authority. It is also important to note that under this 

Act, commercial prospecting or mining is prohibited in any nature reserve. 

Potential for protection of the Uilkraals Estuary 

The Uilkraals Estuary is rated as a very important estuary in South Africa from a conservation 

perspective, having a Biodiversity Importance Score of 75.3 for its size, habitats, and type rarity 

within its biogeographical zone, and biodiversity (Turpie et al. 2004). It ranks highly for birds 

and macrophyte diversity. 

Based on these criteria, there is justification for establishment of a protected area which 

encompasses at least part of the estuary. Although it would be highly desirable, based on the 

above arguments, to provide no-take protection to the estuary in its entirety, it would 

probably not be feasible to achieve complete protection of the system. 

Turpie & Clark (2007) conducted a conservation planning exercise in conjunction with the 

estuarine research and management community of the CAPE region under the C.A.P.E. 

Estuaries Management Programme. The study aimed to elicit the minimum set of estuaries 

that would be required to meet conservation targets (i.e. set percentages of habitats and 

populations of estuary-dependent species). Without worrying about costs, this can be done 

with the partial protection (50% of estuary as a sanctuary area) of some 50 of the 159 

temperate estuaries. 

The Uilkraals Estuary was not included in this primary set of 50. When costs and benefits of 

conservation measures were incorporated into the analysis, the configuration changes, and it 

makes sense to afford partial protection to about 80% of estuaries. This creates a good 

argument for a general zonation system to be applied to most South African estuaries in which 

50% of the estuary is declared a no-take zone. The Uilkraals Estuary was included in this latter 

selection - when estuary value and management costs were taken into consideration. 

Recommendations and procedure for establishing a protected area 

With the lack of development around the estuary, the establishment of a protected area is 

highly feasible and would be strongly recommended. The protection should include a 

substantial no-take zone or zones and the protected area should extend to supratidal 

saltmarsh areas and to some of the fringing terrestrial area. 

Under current regulations, this would require establishment of a nature reserve that contains a 

marine protected area, both of which would be managed by a single authority. A nature 

reserve is needed in order to protect areas above the high tide mark (important fringing 

habitats) that the marine protected areas act does not cover, and in order to protect the 

estuarine habitat areas a marine protected area needs to be established so that zoning of the 

estuary can be developed. Specific recommendations, to be further developed in consultation 

with stakeholders, are as follows: 

1. Establish a nature reserve encompassing as much of the land around the estuary as 

possible including supratidal estuarine habitats; 


68 


2. Establish a Marine Protected Area on the estuary incorporating the most significant 

bird habitats and fish nursery areas as well as a representative section of all habitat 

types present in the estuary (mudflat, salt marsh, submerged and emergent 

vegetation) 

3. Develop a zonation plan in which 50% of the MPA (not necessarily contiguous) is 

declared a no-take zone; 

4. The whole protected area to be managed by the provincial (CapeNature), district 

(Overberg District Municipality) or local (Overstrand Municipality) authority. 

The details of the above will have to be finalised in consultation with stakeholders. Anchor 

Environmental Consultants will draw up a detailed management plan including plans for the 

proposed protected area based on outcomes of the consultative process. 

5.8 Potential and need for restoration on the Uilkraals Estuary 

There is no specific legislation pertaining to the restoration of ecosystems. The estuary has 

been highly modified and is classified as being largely modified, and has been identified as one 

in which there is a need for rehabilitation. In the case of the Uilkraals Estuary restoration of the 

estuary to a better state of health would be straightforward, and would mainly entail (in order 

of priority): 

1. Restoration of the quantity of freshwater inflows; 

2. Restoration of water quality; 

3. Removing significant obstructions to flow; and 

4. Removal of alien vegetation. 

In general, the degree to which these factors should be managed to restore the health of the 

system depends largely on the vision that is developed for the estuary, and on its future 

protection status. Protection status will provide a strong case for the provision of restoring 

flow quality and quantity. 


69 


6. REFERENCES 

Adams, J.B., Bate, G., & O'Callaghan, M. 1999. Primary producers. In: B.R. Allanson & D. Baird 

(Eds.) Estuaries of South Africa, pp 91-117. Cambridge University Press, Cambridge. 

Adams, J.B., Bornman, T. & C. Bezuidenhout. 2006. Olifants/Doring Ecological Water 

Requirements Study Appendix D: Macrophyte specialist study. 

Barbier, E.B. 1994. Valuing environmental functions: tropical wetlands. Land Economics 70: 

155-173. 

Barnes, K.N. 1996. Specialist bird report on the proposed resort development on Farm Sand 

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APPENDIX 1: TERMS OF REFERENCE 

The development of the Uilkraals Estuary Management Plan will be carried out in two phases, 

as follows: 

Phase 1: Situation Assessment 

1. Review of legislation pertaining to the management of environmental threats within 

estuaries 

The focus of this task will be explaining the specific relevance of legislative instruments 

highlighted in the generic legislative review compiled for the GEMP, on how interaction of 

the respective Governmental Departments will affect management of the Olifants estuary, 

and also the relevance of any local by-laws to management of the estuary. A summary of all 

relevant information will be included in the Phase 1 Situation Assessment Report. 

2. Description and GIS map of the estuary 

A clear GIS map of the estuary will be prepared indicating important biophysical features 

(open channel area, macrophyte beds, invertebrate beds, etc.), protected/conservation 

areas, areas earmarked for rehabilitation, land-use and planning provisions of surrounding 

lands, infrastructure (e.g. roads, bridges), cultural & heritage sites, recreational activities 

(e.g. swimming, boating), living resource exploitation (e.g. bait collection, fishing areas, etc), 

mariculture activities, wastewater discharges (sewage, industrial), stormwater drains, and 

solid waste dump sites. 

3. Description of goods and services provided by the estuary 

Information on goods and services provided by the Uilkraals Estuary will be extracted from 

any relevant literature and studies completed on the system. 

4. Identification of issues relating to the exploitation of living resources 

A brief description of current levels and trends in exploitation of living resources in the 

Uilkraals Estuary will be provided, and on the likely impacts of this harvested on goods and 

services provided by the system. 

5. Synopsis of water quantity and quality requirements 

Details on water quantity and quality requirements of the system will be extracted from 

studies and any information that can be obtained from DWAF on the system. 

6. Determination of priority restoration actions. 

All issues affecting or impacting on the health of the estuary will be identified, prioritized and 

specific rehabilitation measures proposed. 

7. Determination of protected area potential 

Protected area potential of the Olifants estuary will be assessed using information provided 

in the recently completed C.A.P.E. Estuaries Programme: Classification, prioritization, 

protection and rehabilitation document as well as other relevant documents. Specific 

recommendations will be provided as to the type of protection that should be applied and 

associated application procedure that must be completed in order to achieve this status. 


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8. Plan for awareness-raising and public participation/stakeholder involvement 

A generic awareness programme for the Olifants estuary will be prepared that will include 

details on processes for involving relevant stakeholders and user groups in estuary 

management and decision-making processes. Much of the necessary material will be drawn 

from relevant reports produced by the East Cape Estuaries Management Programme. 

9. Work plan and budget for Phase 2 

A detailed workplan and budget for Phase 2 of the project will be prepared and submitted to 

the C.A.P.E. Estuaries Task Team for approval along with the Task 1 Situation Assessment 

Report before work on Objective 2 is initiated. 

Phase 2: Stakeholder consultation and compilation of Estuary Management Plan 

1. Vision & Strategic Objectives 

The primary activity for this task will be to convene a stakeholder workshop aimed at 

developing a local vision and associated objectives for the Olifants estuary. This vision will 

underpin the entire EMP and will need to be consistent with the vision and Strategic 

Objectives for the Estuaries of the CFR and with the findings of the C.A.P.E. Estuaries 

Conservation Planning report (Turpie & Clark 2007). 

2. Management Strategies 

Clear management strategies will be formulated that will ensure that the Vision and Strategic 

Objectives developed for the Olifants estuary are achieved that makes optimal use of 

available financial and human resources. 

3. Estuarine Zonation Plan & Operational Objectives 

Management strategies developed as part of task 2 above will be spatially explicit and linked 

with the GIS map prepared during Phase 1 of the project. This will become the Estuary 

Zonation plan (EZP). Appropriate annotations will be added to the map to ensure that 

management objectives and visions for all sections of the estuary are clearly laid out and 

easy to follow. 

4. Management Action Plans 

Detailed Management Action Plans (MAPs) will be developed to ensure that all defined 

operational objective can be achieved in an efficient and effective manner. MPAs to be 

developed for this purpose will include those dealing with conservation, social issues, landuse 

and infrastructure development, water quality and quantity, and exploitation of living 

resources. Each MAP will include a prioritized list of management actions, related legal, 

policy and/or best practice requirements, monitoring plans, work and resource plans. 

5. Implementation 

A detailed five year implementation plan for the EMP will be developed in which agencies 

and individuals responsible for implementation of all aspects of the EMP are identified. 

Qualifications required by key individuals responsible for implementation of the plan will be 

clearly articulated as will opportunities for capacity building and empowerment of 

Historically Disadvantaged Individuals (HDIs). The implementation plan will take cognisance 

of available human and financial resources. 


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6. Monitoring and evaluation 

An appropriate monitoring programme will be designed for the Uilkraals Estuary with the 

primary objective being the ongoing evaluation of the health of the system and success of 

the EMP. The following key components of the monitoring programme will be defined 

within the monitoring plan: monitoring objectives, parameters (indicators) to be monitored, 

staff and budgetary requirements, spatial and temporal resolution of monitoring activities, 

sampling and analytical techniques to be employed, and protocols for evaluation and 

reporting, and for incorporation of results into the MAPs. 

7. Research 

Focal areas for further research effort that will contribute to improved management of the 

estuary. 


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