Beginning in late January, the Marin Municipal Water District will be performing annual water main flushing to help maintain water quality in areas of Kent Woodlands and San Rafael. The district suspended the flushing program in 2014 due to drought conditions. Crews will be flushing pipes most Wednesdays between approximately 8 a.m. and 2:30 p.m. over an eight-week period from January 28 to March 25.
Water main flushing is recommended by the California Department of Public Health to remove sediment buildup in transmission and distribution pipelines because the sediment can impair water quality.
Depending on water supply conditions, each year MMWD “flushes” approximately 20% of its water mains. To flush a water main, selected hydrants along a section of the main are opened. The high velocity of the released water scours the main, removing any collected sediment. After the chloramine is removed by dechlorination tablets, the water is released onto the street and enters the storm drain system. Flushing averages about 15 minutes for each hydrant.
In addition to water in the street, during flushing customers may notice effects on their own plumbing, including slight pressure drops, air in the lines or “dirty” water. If customers notice these effects, MMWD recommends restricting water use during flushing and then running the cold water for a short time afterward to remove any loosened sediment in the pipeline. The temporary discoloration is not a health concern.
2015 Water Main Flushing Schedule:
Jan. 28: Kent Woodlands (Crown Road)
Feb. 4: Marinwood (Smith Ranch Road)
Feb. 11: West Marinwood (Lucas Valley Road and Creekside Road)
Feb. 25: East Terra Linda / Las Gallinas
Mar. 4: Marinwood (Sky View Terrace and Mesa Vista)
Mar. 11: Northwest Terra Linda / Freitas Parkway
Mar. 18: Los Ranchitos Road
Mar. 25: Santa Venetia (North San Pedro Road)
Media contact: Elisa Ignatius, 415-945-1592, firstname.lastname@example.org