Saint Lucia Sewage Needs

Caribbean Environmental Health Institute

Recommendations and Options for Agency Sewage 

Treatment and Disposal 

HIA 

• Preliminary Screening 

• Aeration in combination with MBR 

• Disinfection (via Chlorination or Ultraviolet light) 

Bottling Plants and Other Significant LW Producers 

• Preliminary Screen and Grit Removal 

• Settling Tanks 

• Anaerobic Filters or Fixed film reactors or Trickling filters or Upflow 

Anaerobic Sludge Blanket (UASB) 

Hotels and Institutions 

• Connect to a municipal sewage disposal system 


Recommendations and Options for Agency Sewage 

Treatment and Disposal EST Directory 

Comprehensive School 

• Septic/Settling Tanks 

• Upflow Filters 

• Intermittent Slow Sand filters 

• Disinfection via chlorination or Ultraviolet Light 

• Discharge to tile field water course or the sea 

St. Judes Hospital 

• Has existing septic tanks 

• Upflow Pea gravel filters and slow sand filters 

• Disinfection step using preferable ozone 


Results of Community Survey 

Monthly Family Income 

Need For a Sewage Management Plan 

EC3001- 

5000 

23% 

EC5001- 

10000 

4% 

D/K 

27% 

Stakeholders 

< 

EC$3000 

73% 

No 

13% 

Residents 

WASCO 

MPDEH 

Private Sector 

Government 

MOH 

Yes 

60% 

Type of Toilet Facilities 

Need for Improvement in Sewage Treatment and 

Disposal in the Community 

Pit 

Latrine 

39% 

Water 

closet 

57% 

D/K 

38% 

No 

30% 

Yes 

32% 

Improvement Measures 

•Central STP; 

•Education/awareness 

•Enhance Drainage 

•Implement Laws 

•Political will 

Improvement Benefits 

•Reduce Marine 

Pollution 

•Healthier Community 

•Disease Prevention 

•Enhance Tourism 

•Better Environment 

•Sewage Management 


Recommendations and Options for Community 

Sewage Management 

Vieux Fort Town - wastewater collection and treatment system 

– Preliminary Screening; 

– Primary Settling; 

– Aeration or Extended Aeration; 

– Secondary/Biological Treatment; 

– Tertiary Treatment; 

– Disinfection; 

– Final Discharge. 

Rural Districts – Septic Tanks and Upflow filters with chlorination 

system for surface discharge 

Laborie and Savannes Bay - small bore sewerage networks with 

communal treatment of septic tank effluent via upflow filtration 

and chlorination via tablets before discharge is recommended. 


Water Quality and Effluent Monitoring 

30 March 2006 

Figure 1. Vieux Fort sewage needs assessment project 

14 

Coastal habitats and water sample stations 

13 

Savannes Bay 

12 

15 

Saltibus Pt. 

Sapphire 

Laborie 

1 

Mankótè 

mangrove 

16 

2 

3 

4 

Black Bay River 

11 

18 

5 

Black Bay 

V 

x 

i e u 

F o r t R 

i v e r 

Vieux Fort 

legend 

coastline 

6 

7 

8 

10 

Anse 

de Sables 

Maria 

Islands 

beach 

drainage 

seagrass 

reef 

17 

9 

1-20 

sample stations 0.5 0.0 0.5 

1:31,000 

Kms 

KILOMETRES 

1: 31,000 

0 1 

1 2 3 

KILOMETRES 


Findings From Water Quality Monitoring 

Sampling Areas 

Marine Waters 

Mouth of Rivers 

Industrial Effluent 

Main Findings 

•Bacteriological counts were within guideline values in most cases 

•Elevated levels of nitrates and phosphates 

•Microbiological indicators exceeded guideline values 

•Nutrients exceeded guideline values in most cases 

•Nutrients exceeded guideline values for Class I 

•Total suspended solids exceeded guidelines for Class I 

•Most BOD 5 

values are within guideline values 

Domestic End of Pipe Standards 

Ambient Marine/Coastal Water 

pH 6 – 9 

TSS (mg/l) Class 1 – 30 

Class 2 – 150 

BOD 5 

(mg/l) Class 1 – 30 

Class 2 – 150 

Nitrate (mg/l) Class 1 – 5 

Class 2 – 45 

pH 

Salinity ppt 

Temperature o C 

Turbidity NTU 

Total Suspended Solids mg/L 

Dissolved Oxygen mg/L 

7.0 – 8.7 

30-38 

Black Bay River 

Mapping of the Coastal Waters of the Project Area 

13 April 2006 

Figure 1. Vieux Fort sewage needs assessment project 

Coastal habitats 

Savannes Bay 

Saltibus Pt. 

Sapphire 

Laborie 

Mankótè 

mangrove 

Black Bay 

V 

i e u x 

F o r t 

R 

i v e r 

Vieux Fort 

legend 

coastline 

Anse 

de Sables 

Maria 

Islands 

beach 

drainage 

seagrass 

reef 

mangrove 

0.5 0.0 0.5 

1:33,000 

Kms 

KILOMETRES 

1: 33,000 

0 1 

1 2 3 4 

KILOMETRES 


Sandy Beach 

Mankote 

Savanes Bay 

Maria Island Reef 

Mariculture 

Laborie Reef 


Water Bodies Classification 

Choice of Marine Outfalls 

• Hydrogeology, limited space and exorbitant cost preclude 

alternatives; 

• Complete recycling is beyond that which the economic status of 

SIDS can maintain; 

• Obtaining technology and subsequent operation of tertiary 

treatment plants for sewage on a large scale is a challenge 

‣ Reliance on oceanographic processes of the natural environment to 

reduce the impact of partially treated effluent. 


Parameter 

Effluent Limit 

Total Suspended Solids 150 mg/L * 

Biochemical Oxygen Demand (BOD 5 ) 150 mg/L 

pH 

5 – 10 pH units 

Fats, Oil and Grease 

50 mg/L 

Floatables 

Not visible 

* Does not include algae from treatment ponds 

Parameter 

Effluent Limit 

Total Suspended Solids 

30 mg/L 

Biochemical Oxygen Demand (BOD 5 ) 30 mg/L 

pH 

5 – 10 pH units 

Fats, Oil and Grease 

15 mg/L 

Floatables 

Not visible 

Faecal Coliforms 

Faecal Coliform: 200 mpn/100 ml; or 

(Parties may meet effluent limitations a. E. coli:126 organisms/100 ml 

either for faecal coliform or for E. coli b. enterococci: 35 organisms/100ml 

(freshwater) and enterococci (saline 

water) 

* Does not include algae from treatment ponds

Classification of Marine Waters of Vieux Fort 


Recommendations Water Bodies Classification 

• Establish a team of resource persons 

• Sourcing of information on existing resources and conditions from previous 

studies 

• Stakeholder and public consultation 

• Make maximum use of the available national digital information database 

• Incorporate local knowledge 

• Collect information from CSO and NDC on the community population 

dynamics and generators of liquid waste 

• Survey the communities, businesses and institutions 

• Engage significant generators of liquid waste directly 

• Public education and awareness on Cartagena Convention and LBS Protocol 

• Map the receiving waters as Class I or Class II 

• Amendment of laws and regulations 

• Develop an inventory of agencies and institutions generating liquid waste 

• Develop and implement a compliance monitoring programme 

• Enforcement of regulations 


Lesson Learnt 

• Consultation – key stakeholders, engagement of the public 

• Project Team – A well ‘rounded’ project team members needed 

• Guidelines – Comprehensiveness of the Tetra Tech (2003) guidelines 

• Integrated Approach –Inter-sectoral coordination between 

government agencies and non-governmental entities overlapping roles 

and responsibilities 

• Engage Significant Liquid Waste Generators Directly – NHC, 

NDC et 

• Appropriate Technologies –The absence of approved means of 

excreta disposal is a concern along with the existing liquid waste 

disposal methods used by some industries 


Lesson Learnt 

• Data and Information – Secondary data and information were vital 

elements of the SNA Study. 

• Education and Awareness – highlighted by the agencies and 

communities as prerequisite to the success of any sewage management 

programme. This aspect is also necessary for the replication of the 

SNA Project at the national and regional levels. 

• Poverty Alleviation – Improving the social and economic status of the 

residents of the project study area is necessary to improve liquid waste 

management. 

• Precautionary Principle – The need for the application of the 

precautionary principle in the absence of hard scientific data and 

information to guide the formulation of recommendations. 


Thank You

Saint Lucia Sewage Needs

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