The lake 'Zalew Mietkowski ' is the largest water body in Lower Silesia. It was created by building a dam on the river Bystrzyca in Mietków. The dam is 3.2 km long and 17 m high. The lake has the area of over 9 km2 and the maximum depth of 13 m. The bottom is constantly deepened, as the lake is still mined for rock aggregate. Its construction was completed in 1986. The lake is known troughout the region as a paradise for anglers. It is famous for perch-pikes, breams, carps, tenches, pikes and perches. Many different species of birds inhabit the area and as a result of this, it has been protected by the Natura 2000 program.