The Sulejowski Reservoir (Polish: Zalew Sulejowski, pronounced [zalɛv sulɛjovski]) is an artificial lake, a reservoir created by a dam, built in the years 1969-1974 in the Łódź Voivodeship. The aim of this reservoir was to supply fresh drinking water to the city of Łódź and Tomaszów Mazowiecki. At full capacity the reservoir contains up to 95,000,000 cubic metres (77,000 acre⋅ft) of water and has an average depth of 3.3 metres (11 ft).