Implementation of the Water Framework Directive and other ...

Wastewater treatment and WFD 1 st December 2005
implementation in CEE Danube countries Bratislava, Slovakia
Pressures by organic oxygen depleting pollution � Saprobic risk
Pressures by plant nutrients (nitrate and phosphate) � Trophic risk
Pressures by specific pollutants � Chemical risk
Pressures by hydromorphological alterations of surface waters � Structural risk.
Table 4: Risk assessment of rivers – German Danubian part
Risk category Not at risk Risk unclear At risk
Saprobic risk 65 % 18 % 17 %
Trophic risk 67 % 5 % 28 %
Chemical risk 97 % 2 % 1 %
Structural risk 29 % 37 % 34 %
(Figures in % of river stretches)
The assessment of rivers deliberately has been separated into the four risk categories to make
clear different problems of water quality and their specific causes. Another reason for a
multiple assessment is a fundamental difference in the importance of these categories for a
good ecological status. For achieving a good status of a water body the biological and
chemical criteria are decisive whereas hydromorphological criteria are only supporting
elements and have more importance for the allocation of possible measures.
The assessment of lakes and groundwater is not presented in this contribution, but is available
on www.wasserrahmenrichtlinie.bayern.de .
The Conference of the Environment Ministers of the German Federal States in May 2005
declared based on the reports of all 16 Federal States that the key issues in order to reach the
good status in 2015 are
o Diffuse nutrient pollution (particularly agriculture)
o Hydromorphological alterations (due to dense settlement and long civilization in
Germany)
o In very few cases punctual pollution by hazardous substances
6 COMBINED APPROACH
There are essentially two strategies applied for reaching the goals of pollution control.
On the one hand we have the fixed emission standard approach and on the other hand the
environmental quality standard approach. The German national water protection policy was,
from 1945 onwards, predominantly based on the fixed emission approach.
The fixed emission approach is based on the assumption that anyone who discharges
wastewater into a water body must at least purify this wastewater in compliance with the set
standards, which must comply with the best available technology. The status of the water into
which the wastewater is discharged is of no relevance in this context. The environmental
quality standard approach, on the other hand, takes the actual or desired status of the receiving
water as a basis. Requirements for the discharge may differ substantially depending on the
conditions in the receiving water.
The environmental quality standard approach is sometimes criticised because of the lack of
knowledge in the interpretation of the receiving water status and the necessary huge
monitoring work. On the other hand, others say that particularly in the case of small water
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