Water Framework Directive Intercalibration: Central-Baltic Lake Fish fauna ecological assessment methods

The European Water Framework Directive (WFD) requires the national classifications of good ecological status to be harmonised through an intercalibration exercise. In this exercise, significant differences in status classification among Member States are harmonized by comparing and, if necessary, adjusting the good status boundaries of the national assessment methods. Intercalibration is performed for rivers, lakes, coastal and transitional waters, focusing on selected types of water bodies (intercalibration types), anthropogenic pressures and Biological Quality Elements. Intercalibration exercises are carried out in Geographical Intercalibration Groups - larger geographical units including Member States with similar water body types - and followed the procedure described in the WFD Common Implementation Strategy Guidance document on the intercalibration process (European Commission, 2011). The Technical report on the Water Framework Directive intercalibration describes in detail how the intercalibration exercise has been carried out for the water categories and biological quality elements. The Technical report is organized in volumes according to the water category (rivers, lakes, coastal and transitional waters), Biological Quality Element and Geographical Intercalibration group. This volume addresses the intercalibration of the Lake Central-Baltic Fish ecological assessment methods. Part A: This document comprises an overview and detailed descriptions of fish-based lake ecological assessment methods. Part B describes the construction of multiple pressure index in the Central-Baltic region. Part C describes the procedure and results of the boundary harmonisation of national fish-based lake assessment systemsJRC.D.2-Water and Marine Resource

Intercalibration of the national classifications of ecological status for Central-Baltic Lakes: Biological Quality Element: Fish fauna: Part B and C

The European Water Framework Directive (WFD) requires the national classifications of good ecological status to be harmonised through an intercalibration exercise. In this exercise, significant differences in status classification among Member States are harmonized by comparing and, if necessary, adjusting the good status boundaries of the national assessment methods. Intercalibration is performed for rivers, lakes, coastal and transitional waters, focusing on selected types of water bodies (intercalibration types), anthropogenic pressures and Biological Quality Elements. Intercalibration exercises are carried out in Geographical Intercalibration Groups - larger geographical units including Member States with similar water body types - and followed the procedure described in the WFD Common Implementation Strategy Guidance document on the intercalibration process (European Commission, 2011). The Technical report on the Water Framework Directive intercalibration describes in detail how the intercalibration exercise has been carried out for the water categories and biological quality elements. The Technical report is organized in volumes according to the water category (rivers, lakes, coastal and transitional waters), Biological Quality Element and Geographical Intercalibration group. This volume addresses the intercalibration of the Lake Central-Baltic Fish ecological assessment methods. This volume on intercalibration of the Lake Central Baltic Fish ecological assessment methods is split into three parts: Part A, a document that provides an overview and detailed descriptions of fish-based lake ecological assessment methods. Parts B and C: This document comprises two Parts, B and C. Part B describes the construction of multiple pressure index in the Central-Baltic region. Part C describes the procedure and results of the boundary harmonisation of national fish-based lake assessment systems.  JRC.D.2-Water and Marine Resource

Defining Chlorophyll-a Reference Conditions in European Lakes

The concept of “reference conditions” describes the benchmark against which current conditions are compared when assessing the status of water bodies. In this paper we focus on the establishment of reference conditions for European lakes according to a phytoplankton biomass indicator—the concentration of chlorophyll-a. A mostly spatial approach (selection of existing lakes with no or minor human impact) was used to set the reference conditions for chlorophyll-a values, supplemented by historical data, paleolimnological investigations and modelling. The work resulted in definition of reference conditions and the boundary between “high” and “good” status for 15 main lake types and five ecoregions of Europe: Alpine, Atlantic, Central/Baltic, Mediterranean, and Northern. Additionally, empirical models were developed for estimating site-specific reference chlorophyll-a concentrations from a set of potential predictor variables. The results were recently formulated into the EU legislation, marking the first attempt in international water policy to move from chemical quality standards to ecological quality targets

WG ECOSTAT report on common understanding of using mitigation measures for reaching Good Ecological Potential for Heavily Modified Water Bodies - Part 3: Impacted by drainage schemes

Hydromorphological alterations for drainage are widespread pressures on water bodies in Europe. Because of the importance of the water uses relying on drainage schemes, such as agriculture and urban areas, not all necessary restoration measures can be taken without significant adverse effect on the water use. Therefore many of the affected water bodies have been designated as heavily modified (HMWB). Still, in a substantial number of these water bodies, some mitigation measures should be taken to reach Good Ecological Potential (GEP). This report presents responses of European countries on a detailed questionnaire distributed in 2015 on the impacts of land drainage on the water environment and the measures that can mitigate those impacts. The questionnaire also included questions on impacts of flood prevention, presented in the accompanying report “Part 2: Impacted by flood protection structures”. A key objective of the questionnaire was to compare the understanding of impacts caused by drainage to continuity, hydrological regime, morphological alterations and aquatic biology. Information was requested on 1) national definitions of drainage and existing guidelines, 2) water uses and regulatory regimes linked to drainage, 3) hydromorphological alterations due to drainage and their assessment, and 4) mitigation measures. A list of mitigation measures and their definition is presented. In total, 20 countries responded to the questions on land drainage. Key findings of the exercise are as follows: • Comparing the mitigation expected for good ecological potential by different countries provided a good basis for identifying similarities and differences between those countries’ standards for good ecological potential. It also provided a valuable opportunity for the exchange of information. • It is possible to reach a harmonized understanding between countries of the environmental objective for HMWBs impacted by drainage. • There is no common EU wide definition of the term drainage, although a common understanding exists of what it entails. • There are several methods to detect impacts from hydromorphological pressures and many countries do not have methods to detect all the parameters affected by drainage. • There is no common understanding on minimum ecological requirements for GEP related to impacts from drainage. • The standard for ecological potential seems to vary between water bodies and countries and few countries have a national definition on significant impact on water use. • There are some indications that the majority of countries probably rule-out mitigation measures when considering (often site-specific) evaluating criteria. • It would be interesting to compare different countries’ national methods to a common and comparable set of water bodies/catchments impacted by drainage. Such an exercise would be valuable in further identifying and elaborating on emerging good practice, implementation of measures in practice and possibly also for handling multiple pressures and intercalibrated Ecological Quality Ratios/Methods related to e.g. pollution in a comparable way. Key recommendations for next steps presented in the conclusions of this report include: • A generalised framework for deciding on the mitigation required for good ecological potential should be developed to achieve further harmonisation of GEP. Such a generalised framework can be used to supplement CIS Guidance no. 4 on HMWB. • The existing approach should be further developed to allow for harmonizing the levels/requirements of ecological potential based on mitigation measures. • Future exercises under the Common Implementation Strategy should use the common technical terminology and mitigation measures provided in this report. • Harmonized hydromorphological classification methods should be developed in order to have a comparable assessment of the hydromorphological alterations due to drainage, among the different countries. • More common understanding on ecological minimum criteria for GEP should be developed. • Countries should exchange and establish transparent criteria for deciding if mitigation would have a significant effect on drainage and benefits for society. • Reasons for ruling out measures should be made clear and more transparent . It is recommended to compare the outcomes produced by countries’ national methods by applying them to a comparable set of heavily modified water bodies included in generic cases. Consideration should then be given to incorporating the results of both exercises into a good practice guideJRC.D.2-Water and Marine Resource