Large Water Valve and Vault Retrofit, Silver Spring, MD

This project involves replacement of existing 24-inch valve and vault installed in 1999, with new 24-inch valve. The project is located near the intersection of Randolph Road and Old Columbia in Silver Spring, MD Montgomery County, within the 495A pressure zone The primary function of a valve of this size is to isolate sections of the transmission main during repairs and replacement work.Proper function of this valve minimizes the length and time that this transmission main is down during work on this water main.The condition of large valves is based on leak and repair history, inspection results, operational status, age and condition.Troubled valves are typically identified during the inspection or operation of said valve and reported to the Utility Service and/or System Controls Divisions.The order of replacement is then primarily driven by failure mechanism, importance and location of the valve. This valve is part of 24-inch transmission main that transports water to the Colesville Elevated tank.The valve was identified in 2019 for replacement by the Utility Services Division as a result of an inspection, that found the valve stem to be free spinning, blind flanged and missing internal gates.Ultimately the valve couldnt be repaired and was recommended for replacement.With this valve being inoperable, it can affect the level of service and ability of WSSC to provide water to a significant number of customers in both commercial/industrial and residential locations as well as the water levels in the Colesville Elevated tank within southern Montgomery County.