D10: Impact of Contaminants - Hydromod

Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas
EUROLAKES
D10: Impact of Contaminants
FP5_Contract No.: EVK1-CT1999-00004
Version: 4.0
Date: 25/07/01
File: D10-vers.4.0.doc
Page 86 of 136
rocks gives a good indication of the potential natural richness of the lake waters draining
from them.
Loch Lomond is an important source of portable water for two supply schemes, with a
total ultimate yield of 454 megalitres per day. Because of its good water quality - the
European Community classification of water intended for humans consumption grades
Loch Lomond the highest quality - Loch Lomond is also important as a reservoir for
public water supply and hydro-electricity generation at Loch Sloy hydroelectric power
station [SEPA 2000c].
Data of Land Use with Relevance to the Water Supply
In the two northern sub-catchments, the Falloch (area 113 km²) and the Inveruglas
(area 158 km²), lie entirely to the north and west of the Highland Boundary Fault, an
important geological festure which crosses the southern part of the lake. The land is
used for upland sheep-grazing (87 % of the catchment area, although forestry is also
important (8 % of the catchment area). The northern sub-catchments are relatively underpopulated
with little urban development. The two southern sub-catchments, the
Fruin (area of 161 km²) and the Endrick (area of 264 km²), lie to the south and east of
the Highland Boundary Fault. Here is more arable farming (26 %) although large areas
are still used fore rough grazing (56 %) and forestry (13 %).
The 'Loch Lomond Catchment Management Report' published by the Scottish Environment
Protection Agency (SEPA) states that Loch Lomond and its catchment are an
important water supply, essential for the social and economic well-being of Central
Scotland. However, these resources are coming under increasing pressure from potentially
conflicting uses and activities, including recreation and tourism, forestry, agriculture,
power generation and water abstraction. Approximately 9 % of the catchment is
covered by water, compared to 35 % for agricultural land and 13 % for forestry. Urban
and industrial areas in comparison account for less than 2 % of the land cover [SEPA].
Agriculture has played an important role in shaping the landscape and defining the
character of the Loch Lomond catchment. The report says forestry plays an integral role
in the landscape and history of the Loch Lomond catchment. In the past, forestry practices
have caused a number of environmental problems within the catchment. However,
recent years have seen attempts, including the introduction of the Forest and Water
Guidelines, to counteract many of these negative impacts. The restructuring of commercial
woodlands and an increase in the development of native and riparian woodlands
have also been beneficial [SEPA].
Pollution Sources in the Catchment Area of Loch Lomond
Due to the size of lochs and the diluted nature of any pollutants, water quality problems
often take a long time to become apparent.Forestry, in particular coniferous forestry,
exacerbates the problem by scavenging atmospheric pollutants [SEPA 2000c].
Along the shore of the lake there are numerous single dwellings, camping and caravan
parks, youth hostels, hotels and small villages which discharges effluents directly or indirectly
into Loch Lomond. Discharges are also received from the surrounding forest