The invention relates to a low overflow dam
cave depot type
hydropower station. An low overflow dam is built at the upstream position of a river with an arc-shaped way; a
water diversion tunnel
cave depot of which the
water diversion amount reaches or exceeds the
annual average runoff of the river is built between the upstream position and the downstream position of the arc-shaped way of the river; the water inlet of the
cave depot is positioned at the upstream position of the low overflow dam; a submerged front
pool of which the top is lower than the body of the low overflow is built, or a channel of which the
diameter is greater than that of the opening of the cave depot is built at the front end of the water inlet of the cave depot for
water diversion from the cave depot, and a gate is built on the channel; a blocking wall body and a longitudinal water diversion pipeline are arranged at the water outlet
tail end of the cave depot; the longitudinal water diversion pipeline is arranged in the blocking wall and used for connecting the cave depot with a water-
turbine generator set outside the cave depot; the low overflow dam refers to that the dam body can be partially percolated by
river water, part of the
river water can overflow the top of the low overflow damp to flow downstreams in the high water period, and part of the
river water seeps from the dam body and flows towards a dam body at the downstream position. The low overflow dam cave depot type
hydropower station does not need to
cut off the river, can be built on a river with a small or even very
small head drop, further increases the utilization ratio of
hydropower resources, and is low in construction difficulty.