D10: Impact of Contaminants - Hydromod

Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas
EUROLAKES
D10: Impact of Contaminants
Land Use in the Bourget Lake Catchment
FP5_Contract No.: EVK1-CT1999-00004
Version: 4.0
Date: 25/07/01
File: D10-vers.4.0.doc
Page 83 of 136
The Chambéry and Aix les Bains area is a very urban area with specific orchards on La
Motte Servolex. Chambéry, expect the city, are some agricultural area near the city. La
Motte Servolex with orchards and in the south vine. On the west side and east of the
lake between Aix les Bain and Chautagne there are many forests. In the north part of
the catchment in the Chautagne area are agriculture and forests and in the Albanais
area are cattle and pigs.
The upland areas of the Leysse catchment, i.e. the catchments of the upper Leysse
and the Hyère-Albanne tributaries, are mainly rural. Agriculture and cattle farming predominate,
although this is limited by the steep gradients, the climate and the inaccessibility
of the area. Forests cover approximately 50 % of land in this part of the catchment.
In contrast, the lowland areas of the Leysse catchment are much more heavily
populated (> 650 per km 2 ), urbanised and industrialised, particularly in the environs of
the city of Chambéry. Outside the urban areas, fruit, wine and cereal production is well
developed. There is an average population density of 321 people per km 2 in the whole
catchment.
Pollution Sources and Antropogenic impacts
In the Bourget Lake catchment area are 15 sewage treatment plants with a total
capacity of 387 450. Details are listed in Table 10-5.
Name Capacity of sewage treatment plant
Aix les Bains 70000
Albens 3000
La Boille 1500
Le Bourget du Lac 4500
Chambéry 290000
Chindrieux 1000
Conjux 300
Les Deserts 150
La Féclaz 2500
Ruffieux 600
Saint Félix 10700
St Thibaud de Couz 200
Serrières 600
Technolac 2000
Le Montcel 400
Table 10-5: Sewage treatment plants in the Bourget Lake catchment
Despite Bourget Lake’s attractive appearance, it is vulnerable to anthropogenic impacts
that affect its fragile biological balance. The main threats to its ecological status are
thought to be from the impacts of diffuse agricultural pollution (e.g. pesticides and
nutrient enrichment), transport related pollution (e.g. run-off from roads and accidental
spillage) and domestic and industrial effluents (particulary from Chambéry and Aix-les-
Bains). Most of the domestic and industrial effluents are re-routed after treatment