Water-discharge installation arranged at a considerable depth beneath the ground, and method of operating the installation

摘要

Provided in the ground, at a considerable depth, is a duct into which there flows rainwater from flood-regulating ducts, pipelines and rivers, through vertical shafts. The pumping shaft of a pumping station is connected to the downstream end of the underground duct. Water flowing into the pumping shaft is delivered by a pump to a discharge tank. All in all, the pump is arranged on a central water level of the underground duct. The lowest water level LWL which permits a discharge is the central water level of the underground duct. The installation may operate with open duct flow and closed duct flow. In the case of open duct-flow operation, the water level of the underground duct is kept at the lowest water level LWL. In the closed duct-flow operation, the underground duct is filled with water, it being possible for the water level in the vertical shafts to rise. By changing an outflow factor in accordance with a precipitation pattern, the quantity flowing into the vertical shafts can be accurately determined, with the result that the water-discharge installation arranged at a considerable depth beneath the ground can be operated in a stable manner. <IMAGE>