Located within cities urban recreational reservoirs (URRs), both natural and man-made, are popular resting places and holiday destinations for local residents and tourists. These sites, often accompanied by waterfront infrastructure, also act as places of increased anthropogenic pressure on the reservoir ecosystem. For example, urban lakes and in particular beaches in the Masurian District in Poland, are mostly exploited during the summer season when hundreds of thousands of tourists arrive for holidays and seasonally multiply populations of local villages, towns, and cities.
