SUPERNATANT WATER DISCHARGE DEVICE

PROBLEM TO BE SOLVED: To provide a supernatant water discharge device that can prevent an overflow of a sedimentation basin due to concentrated heavy rain.SOLUTION: The device comprises: a submersible pump 10 provided in a first sedimentation basin D; a float member 30 that makes the submersible pump 10 float on the water surface; a distance sensor 41 that measures the distance to a sediment S; an anemometer 42; and a control device 50 that stops the submersible pump 10 when a measurement value of the distance sensor 41 or the anemometer 42 reaches a threshold value. Concentrated heavy rain is predicted and discharge of supernatant water S to a second sedimentation basin P can be stopped, and therefore, an overflow from the second sedimentation basin P because of concentrated heavy rain can be prevented. If the sediment S gets close to the submersible pump 10 because of a drop in the water level or a rise in the height of the sediment, the submersible pump 10 can be stopped, and therefore, failure of the submersible pump 10 caused by suction of solids can be prevented. 【課題】沈殿池が集中豪雨により溢れ出すことを防止できる上澄み水排出装置を提供する。【解決手段】第１沈殿池Ｄに設けられた水中ポンプ１０と、水中ポンプ１０を水面に浮揚させる浮揚部材３０と、堆積物Ｓまでの距離を測定する距離センサ４１と、風速計４２と、距離センサ４１または風速計４２の測定値が閾値に達した場合に水中ポンプ１０を停止させる制御装置５０とを備える。集中豪雨を予測して第２沈殿池Ｐへの上澄み水Ｓの排出を停止できるため、第２沈殿池Ｐが集中豪雨により溢れ出すことを防止できる。水位の低下や堆積高さの上昇により水中ポンプ１０に堆積物Ｓが接近すると水中ポンプ１０を停止できるため、固形分の吸引による水中ポンプ１０の故障を防止できる。【選択図】図１