The city’s Water Division will begin its annual hydrant flushing program on Thursday.
Through March, flushing will take place in portions of northern Napa, Browns Valley, Alta Heights, Soscol Gateway, Napa Valley Corporate Park and Silverado Country Club.
Hydrant flushing is a periodic maintenance activity to clean and flush Napa’s water mains, the city said in a news release. Fire hydrants are opened to move a large volume of water at a higher-than-normal velocity, which scours the pipes of particles and minerals that have settled.
This may cause periods of discolored water and reduced water pressure in areas where flushing is being conducted. The water will remain safe to use and generally clears within a few hours. Residents should monitor their water prior to starting laundry, especially when washing white clothes.
Flushing operations may also activate low-pressure alarms on automatic fire sprinkler systems due to temporary reductions in water.
Dechlorination tablets are used to remove chlorine in the water before it goes into the storm drain system and eventually into the Napa River. Due to the high volume of water flowing from the hydrants, the dechlorination tablets may cause some bubbling of the water, giving it a soapy appearance. The tablets are environmentally safe and are used to protect the river, the city said.
The Water Division will update the city’s website daily to provide a map of the region being flushed each day and a map of the region that will be flushed next. The flushing program maps and updates can be found at cityofnapa.org/water.
Contact the Water Division at 257-9521 with any questions or concerns.