A foot valve is a type of non-return valve, with strainers mounted at the open end of the pump suction pipelines. Foot valves are used when the pump has negative suction. These valves are placed at the pumps wet well. The flow area of the foot valves is larger than the pipe size, so there is only less head-loss. Foot valves are known for their ability to keep the continuous presence of suction within the pump. A foot valve is a special design of the lift check valve. These valves are designed for up-flow and are attached to the bottom of a pump suction pipe. Foot valves can cause leakage, when they are used with fluids that have solids, and they are difficult to service. Foot valves would decrease the net positive suction head available.