A valve assembly for a bilge pump system having first and second bilge pumps each connected to a single hull outlet includes a valve body having a first inlet port for connection to the first bilge pump, a second inlet port for connection to the second bilge pump, and an outlet port for connection to the hull outlet. A first one-way valve operates at the first inlet port for allowing flow into the first inlet port to the outlet port and preventing flow out of the first inlet port from the second inlet port and/or the outlet port. A second one-way valve operates at the second inlet port for allowing flow into the second inlet port to the outlet port and preventing flow out of the second inlet port from the first inlet port and/or the outlet port. The valve assembly enables the second bilge pump to be connected to the single hull outlet and eliminates the need to cut an additional outlet opening in the hull.