Summary:

Poland as a member of European Union was obligated to implement the Water Framework Directive. One of main purposes which are contained in the Directive is to achieve a good water status until 2015. In order to identifying ecological and chemical water status results of monitoring measures will be used. The assessment of ecological status understanding as a degree of deviation from representative value of parameters is performed by using reference conditions. Initial reference conditions for each among 25 types in Poland, which were established as part of river typology were performed by using data from monitoring points, historic data and experts opinions. Heavily modified river water bodies and artificial water bodies were destignated and it were determined-taking into account impacts and pressures-water bodies at risk in achievement the good status in 2015 9according to WFD). In harmony with regulations of WFD, as part of river typology, initial abiotic characteristic (hydromorphological and physicochemical quality elements) was established and a trial of biological verification of reference conditions, with detailed biological quality elements, was performed. Designated values of reference conditions are the base to assess ecological status of particular river, which allows among others to establish degree of river natural state and degree of it's diversity (geomorphological structures, hydrological parameters, weather conditions, landscape factors e.g.) as a result of diverse pressures on particular river.