The configuration of washout valves in watermain systems mirrors that of fire hydrants, where two gate valves are installed in conjunction with a single hydrant. Washout valves facilitate routine maintenance by enabling water drainage during cleaning procedures.
At the junction where a tee branches out to a washout point, a gate valve is installed to isolate the two pipelines. This valve remains open during normal operation while another gate valve, located further downstream, is closed. The presence of this second, normally closed, gate valve is crucial for preventing the branched-out section of the watermain from running dry during regular operation. If this section were to remain empty, it would be susceptible to damage and prone to frequent leakage.
With the downstream gate valve in place, the branched-out segment remains filled with water during normal operation. This ensures that any potential leaks can be easily identified using the two gate valves. By strategically isolating the section, maintenance crews can pinpoint the leak’s location and take remedial action promptly.
In essence, this arrangement of gate valves safeguards the integrity of the watermain system. It prevents the branched-out section from drying out, minimizes the risk of damage and leaks, and facilitates efficient leak detection and repair. This dual-valve configuration proves to be a reliable and practical solution for maintaining the functionality and longevity of watermain infrastructure.