České údolí Reservoir, reservoir in Plzeň, Czech Republic

The České údolí Reservoir, also called Borská or Litická, is a dam on the Radbuza at river kilometre 6.9 in Litice, south of Plzeň. Its 106 m long, 14 m wide earth dam has an arched plan and a concrete sealing face on the water side; the dam crest now carries only a local road between Bory and Litice.

First plans for a dam in the České údolí date from 1959; construction ran between 1969 and 1972 near the Bory prison and the Chlum hill, on the site of an old road bridge by former alum works. The road I/27 from Pilsen to Klatovy ran across the dam crest until 2004, when a new bridge east of the dam opened as a feeder to the D5 motorway and the crest road became a local link between Bory and Litice.

The reservoir takes its name from the České údolí valley, at whose end the dam was built; locals also call it Borská přehrada. It was conceived as a recreation area for the industrial city's workers, and holiday settlements grew around the lake. Since 1989 all public bathing sites have been closed and the operator advises against swimming.

The dam stands at the southern edge of Plzeň in Valcha, with the I/27 road and European route E53 running east of the reservoir and the Železná Ruda–Plzeň railway along its left bank. Swimming is not permitted: all public bathing sites closed after 1989 and the Povodí Vltavy authority still advises against it. In winter the gates are lowered and the level drops by about 3 m.

The reservoir was built as a recreation area for the workers of the industrial city, yet the Radbuza was then the most polluted river in Pilsen, receiving wastewater from the Škoda landfill at Sulkov through the Luční potok. Bathing was banned after 1989 and the operator Povodí Vltavy still advises against swimming; the reservoir now serves only for flood retention.