Freshwater - State and impacts (Poland)

SOER 2010 Common environmental theme (Deprecated) expired
This content has been archived on 21 Mar 2015, reason: A new version has been published
SOER Common environmental theme from Poland
Published: 26 Nov 2010 Modified: 21 Mar 2015

A new system of water status monitoring and classification has now been in place in Poland since 2007. The results of surveillance monitoring indicate that 6.5% of the bodies of flowing water covered by surveys in 2007-2008, meet agreed environmental objectives, achieving a good (class II) or very good (class I) ecological status. The results of an assessment of the ecological potential of artificial and heavily-modified bodies of flowing water are comparable: approximately 4.5 % of those monitored in 2007-2008 meet environmental objectives. However, it should be stressed that these figures are not indicative of the state of water in Poland as a whole, but only show the results of measurements taken from the part of monitoring points in the monitoring network. The full picture will only be known after the completion of a full surveillance monitoring programme, which assumes conducting research on a different set of water bodies each year (so as to assess all water bodies in Poland during a six-year water management cycle). At the same time, as a result of the ongoing work to complete the assessment system and verify the class limits based on an increasing amount of biological data available, the final results of assessment for all water bodies may vary from those presented below.

Fig. 1: Classification of the ecological status of rivers included in surveillance monitoring, 2007-2008 (Source: GIOŚ /PMŚ). The assessment covers different bodies of surface water for the individual years.

Nitrogen concentrations for monitoring points located at the mouths of the two largest Polish rivers (Vistula and Odra) have remained stable over the last three years and much lower than at the end of the 1990s when there was a simultaneous drop in average flows.

Fig. 2: Average nitrogen concentrations at monitoring points Vistula-Kiezmark and Odra-Krajnik Dolny compared to average flows in 1998-2008 (Source: GIOŚ/PMŚ)

Polish lakes are mostly eutrophic reservoirs. Around half of them are characterised by adverse morphometric and hydrographic features and geomorphological conditions favouring the natural process of lake ageing. This means that a eutrophic state is the natural state for many Polish lakes. In total, 98 of the 208 lakes monitored in 2007-2008 were assessed as good or very good.

Fig. 3: Combined results of lake classification by ecological status, as monitored in 2007-2008 (Source: GIOŚ/PMŚ)

Analysis of the data for the nine reference lakes examined in 1999-2008 indicates that the essential parameters for eutrophication (concentration of phosphorus and total nitrogen, concentration of chlorophyl “a” and water transparency) remained stable, although they varied from year to year.

Fig. 4: Changes in total nitrogen concentrations in the waters of the reference lakes, 1999-2008 (Source: GIOŚ/PMŚ)

Eutrophication in flowing waters was assessed based on data from 2004-2007. It shows that eutrophication affects about 62 % of watercourses (eutrophication was found in 2 016 out of 3 268 monitoring points used for the assessment). In lakes, this phenomenon occurs in 268 of the 432 lakes examined.

An examination of groundwater quality made at monitoring stations of the national groundwater quality monitoring network in 2007 shows that the chemical status of groundwater (classes I, II, III) was good at around 80 % of the stations examined, while 20 % had poor chemical status (classes IV and V).


Results of groundwater quality examination at monitoring stations of the national groundwater quality monitoring network as part of operational and surveillance monitoring in 2007



Monitoring stations

Groundwater chemical status (% of stations )




class I


class II


class III


class IV


class V



10.20 %

42.63 %

25.62 %

18.14 %

3.40 %



7.77 %

53.71 %

21.38 %

13.96 %

3.18 %



8.84 %

48.86 %

23.24 %

15.79 %

3.28 %

The chemical status of groundwater bodies was assessed based on examinations carried out at monitoring points. These indicated that, of the 161 ground water bodies selected across the country, only 11 ground water bodies (9.5% of the total area) had a poor chemical status.

Fig. 5: Assessment of the chemical status of groundwater bodies (Source: GIOŚ/PMŚ)

At the majority of the monitoring points of the national groundwater monitoring network nitrate concentrations did not exceed the threshold value of 50 mg/dm3. Moreover, nitrate concentrations were low (below 25 mg/dm3) at about 95 % of the stations.


River monitoring:
Lake monitoring:
Groundwater monitoring:


The country assessments are the sole responsibility of the EEA member and cooperating countries supported by the EEA through guidance, translation and editing.

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