REFCOND Workshop Uppsala, 14-15 May 2001 Comparative analysis of river quality classification schemes in Europe Steve Nixon European Topic Centre on Water

Comparative analysis of river quality classification schemes in Europe Undertaken by the ETC-IW for the EEA Includes EEA countries and PHARE countries Potential source of comparable and representative information for EEA Relevance to the Water Framework Directive Differences and commonalities in national schemes in relation to the needs of the EEA and WFD

Technical aspects that affect comparability type of classification (physical, chemical, biological or integrated) selection of determinands basis of comparison number of classes monitoring requirements

Presentation contents Results from national schemes Extent of classification schemes Determinands used physicochemical biological physical pollutants Basis of comparison (reference conditions) Sampling frequency and sampling window Class defining thresholds

National river classification schemes

Countries included EEA Austria Belgium Denmark Finland France Germany Ireland Italy Luxembourg Netherlands Norway Portugal Spain Sweden UK 15 countries PHARE Bosnia and Herzegovina Bulgaria Croatia Czech Rep. Estonia FYR of Macedonia Hungary Latvia Lithuania Poland Romania Slovak Rep. Slovenia 13 countries

Objectives of classification schemes Assessing ‘general’ chemical or biological water quality including ‘background/ reference quality’ Identifying particular pressures/stressors Helping to identify cause-effect Determining the success or failure of control or reduction measures Demonstrating long-term trends in determinands Identifying suitability of water for particular uses Determining river habitat suitability for aquatic life.

Purpose of river quality classifications in 27 countries Number of countries

Type of river quality classifications used in 27 countries Number of countries

Extent of classification schemes

National river classifications in relation to length of river included Percentage

Lengths of river in each class km of river

Classification schemes and associated determinands

Number of determinands Number of physico-chemical determinands used in 25 national river classification schemes % of schemes Number of determinands

Number of river stations measuring physico-chemical determinands

Number of river stations for different types of determinand

Length of river per station for different types of determinand km

Biological quality elements used in river classification schemes in EU

Use of macroinvertebrates in national river classification schemes

Other biological quality elements used or under development

River classifications based on physical characteristics

Number of pesticide active ingredients monitored for in groundwater in EEA countries France and Norway also monitor their groundwater Number

Number of chemical substances in COMMPS database by country

Sediment/biota classification

Misclassification and the significance of change in class Probability of misclassification depends type and number of variables measured classification design number and width of classes number of sites number of samples sampling frequency E&W 19% risk of misclassification for chemical, and 22 % for biological

Number of classes

Number of classes used in 26 national river classification schemes

Basis of comparisons in classification schemes

Options for comparison in classification schemes comparison of measured levels of the selected determinands in terms of ‘background’ or natural levels in relation to the chance of a biological effect or change in water use occurring direct measures of the biology in relation to reference conditions and changes in ecological quality

Classification in relation to the chance of a biological effect occurring - Water-SEQ

Establishment of type-specific reference conditions type‑specific hydromorphological and physicochemical conditions shall be established representing the values of the hydromorphological and physicochemical quality elements … for that surface water body type at high ecological status Type‑specific biological reference conditions shall be established representing the values of the biological quality elements … for that surface water body type at high ecological status

Reference conditions used in national river schemes - biological quality

Reference conditions used in national river schemes - biological quality

Reference conditions used in national river schemes - physical quality

Sampling frequency and sampling window

Sampling period and sampling frequency (per year) for chemical assessments

Sampling details for biological assessment of rivers in EU

Class defining threshold values

Class defining thresholds -Ammonium mg N/l

Class defining thresholds Orthophosphate mg P/l

Classification statistics

Classification statistics used for chemical assessment schemes (EU)

Concluding comments

Differences between national river classification schemes Types of classification (chemical, biological, habitat, ecological) Type of monitoring network (general, impact, transboundary, loads to sea) Representativeness of monitoring network Number and positioning of sampling stations Number of quality classes used Classification based on sampling site or sampling reach Number and type of determinands used

Differences between national river classification schemes (2) Environmental media analysed Units measured, calculated and expressed for determinands Indices or statistical approaches used to derive summary determinands Sampling frequencies Class-limiting thresholds Inclusion or exclusion of any values suspected of being errors or extreme cases Subjectivity in assigning a sampling site to a class What information is reported Number of years data used for each assessment

Commonalities between national river classification schemes Most countries do have a classification scheme Most include an impact network Most include reference stations though these is most, if not all, cases will not equate to reference conditions as defined by the WFD Most include a number of physicochemical, biological and microbiological elements Most use 4 quality classes

Commonalities between national river classification schemes (2) All analyse water from the water column Most include DO, BOD, phosphorus and nitrogen and many include COD, salts, temperature, conductivity, suspended solids, metals and some organic micropollutants Most use benthic macroinvertebrates in biological assessments Most analyse physicochemical determinands twelve times per year and biological determinands twice per year Most report classification as colour-coded water quality classification maps