Sump Storm Water
Problem: The Park Royal Hotel in Sydney has two large Flygt submersible pumps which operate automatically to pump out storm water and seepage. The pumps are installed in a sump in the basement car park. When the pumps shut down due to low level in the sump, the backflow of the storm water still in the discharge line returned against the check valve at the pump's discharge. This caused severe pipe vibration and water hammer. The force was so great that the pipe, mounted on the basement ceiling with brackets and Ramset dyna-bolts, was dislodged, landing on expensive motor vehicles.