Hydrant Flushing

BEGINS January 2024

Annual Flushing Program

Hydrant Flushing

The City of Napa Water Division will begin our annual Hydrant Flushing Program in January 2024. This year’s program is expected to continue through March.

Hydrant flushing is an important maintenance activity to clean and flush the City water mains. Fire hydrants are opened to move a large volume of water at a higher-than-normal velocity through the mains. This procedure mobilizes particles and minerals that have settled over time and flushes them out of the system. This activity assists the City in maintaining the highest quality of water in the public water system.

View map of the Full City Flushing Area (PDF).


Current Flushing Areas begin January 2024

Current Flushing Area

Current Flushing Area 2

Next Flushing Areas

Next Flushing Area

Next Flushing Area 2

The flushing program may cause periods of discolored water and reduced water pressure in localized areas where flushing is being conducted. The discoloration is due to particles and minerals that have settled in the main being mobilized by the high velocity water before they are discharged through the fire hydrants. The water will remain safe to use and generally clears within a few hours after flushing has been completed. Residents should monitor their water prior to starting laundry, especially when washing white clothes.

Commercial customers, especially businesses that serve the public, should be aware of the water quality while flushing is taking place in their area. Due to the nature of the program, it is difficult to determine the exact day an area will be flushed; however, on average, each flushing set takes 1 to 3 days to complete, depending on the quantity of water mains to be flushed and the number of valves that are operated.

The City thanks Napa residents and businesses for their patience and apologizes for any inconvenience our program may cause. Please contact City of Napa Water at (707) 257-9521 with any questions or concerns, or consult our Frequently Asked Questions (FAQs) below:

  1. Why is hydrant flushing necessary?
  2. What is "unidirectional" flushing?
  3. Who will be affected? What locations?
  4. What impacts will residents and businesses see during the flushing?
  5. What is the City doing to minimize the impacts?
  6. Isn't this a waste of water?
  7. Why don't we just capture the water and reuse it?
  8. Are we polluting the river with the runoff?
  9. If we have any additional questions, who do we call?
View All FAQs