Waterway Main Drain Hydrostatic Relief Valve

Spring Loaded Hydrostatic Relief Valve 

• Relieves the air and water that can build up under pond liners.
• The hydrostatic relief valve threads into 1-1/2" or 2" bulkhead fittings.

A hydrostatic relief valve (commonly referred to as a burp vave) is placed at the bottom of an in-ground pond or swimming pool. Its purpose is to open when excessive ground water pressure builds up allowing the ground water into the pool.