Kočevje Mine Lake (Rudniško jezero)
Kočevje's Mine Lake fills the open-pit brown-coal mine that closed in 1978; the pit slowly flooded and now forms a lake of about 1.5 km² and up to 40 m deep. The bottom slopes gently, so dives can start almost anywhere on the shore. With no through-flow, the temperature plunges to around 3 °C below 15 m all year, visibility is poor and the deep bottom is lifeless silt with tree remains and fishing lines. According to the 2012 PAS sheet all the life is in the warm shallows down to 5 m: small fish, many feisty crayfish and the odd freshwater mussel.
depth: 0–40 m