Deadly bug E. coli is the bacteria found at Pugneys which has forced the closure of the lake.
Wakefield Council said high levels of bacteria were discovered in the water forcing the lake’s closure earlier this month.
It has since been confirmed that it was the E. coli bug, which can cause severe illness in humans and in rare cases, death.
They also found enterococci bacteria, indicators of faecal contamination in the water.
The council says there have been no reported illnesses, but they are continue to work with the Environment Agency who have been testing the water.
They say contamination levels are dropping but the lake will remain closed to water sports until they no longer pose a risk.
Pet owners are advised to also keep their dogs out of the water.
However, water sports at the country park look likely to be suspended, temporarily at least, as part of the council’s upcoming budget cuts.
They say low customer demand and difficulties in recruiting qualified staff means that the water-sports centre requires “significant financial subsidy” from the council and is not commercially viable or sustainable in its current format.
The proposal to suspend activities was approved at the council’s cabinet meeting on Tuesday.