vaata faili - Viru Peipsi

ASSESSMENT OF THE STATUS OF THE RIVERS IN VIRU AND PEIPSI
CATCHMENT AREAS FOR COMPILATION OF WATER
MANAGEMENT PLANS
Summary
The aim of the project was assess the chemical and ecological status of rivers in Viru and Peipsi
catchment areas and classification of rivers according to physical-chemical indicators.
For analysing data of the national monitoring programme in 31monitoring stations , additional
monitoring in 52 stations was carried out. The list of additionally monitored rivers was chosen by
the Life programme coordinator. First of all were chosen objects of insufficient water quality due
to waste water impact, bur also stations of agricultural and background catchment areas.
The report contains following chapters
6. Main task and investigated objects.
7. Overview of hydrology of rivers and land-use in the catchment area
8. Assessment of human impact: analyses of point sources, pollution ingredients of the
waste water, agricultural diffuse pollution, background load and source apportionment of
different pollution sources
9. Status of rivers and adequacy to the quality requirements: Drinking Water Directive, Fish
Directive, Directive of path waters, Nitrate directive.
10. Overview of the monitoring programme and analyse: the water quality classes of rivers
and analyse of quality indicators of water classes; typisation of rivers, proposals for future
in monitoring programmes
11. There are several data in the Annexes for compilation of water management plans
Despite of construction new waste-water plants the chemical status of rivers was worse than
expected. In most cases plants do not work as needed and downstream of discharge of waste
water are rivers in bad conditions and do not correspond to the requirements. Discharges from
329 point-sources don not correspond to the requirements in 186 cases.
The main problem in fish rivers is high content of nitite and ammonium-nitrogen
The runoff from agricultural catchments is small and in the same level as background values
from natural catchments due to low level of agricultural pollution and use of fertilizers. The selfpurification
processes and retention-time are also impontant factors in decreasing agricultural
pollution
Long-term trends show decreasing nitrogen content in Peipsi rivers, but phosphorus content has
been in the same level. Decreasing N/P ratio causes better conditions for cyanobacteria growth in
the lake and coastal areas
Only 13 rivers stations from 84 corresponded to the good quality class requirements. The main
problems were higher content of nutrients in the rivers
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