Water samples were taken from Bystrzyca River and its tributaries (26 points) each month from May 2006 to May 2009 and analyzed for quality (contents of nitrate and ammonia N). Addnl. results of anal. of wastewater samples taken in 2006-2009 from the Bystrzyca river catchment before and behind of 10 municipal and district wastewater treatment plants and analyzed for BOO and contents of N and P were taken into consideration. Water pollution was connected rather with sewage release than with the fertilizing in agriculture.