City of Vacaville

650 Merchant Street
Vacaville, CA 95688

(707) 449-5100

Hydrant Flushing

Font Size: + -

Feedback Print

The City of Vacaville Utilities Department will begin its annual Hydrant Flushing Program no earlier than February 9, 2026, with work continuing through March 2026.

This routine maintenance is critical to maintaining water quality, ensuring fire protection readiness, and preserving the reliability of the City’s water distribution system.

Program Area and Schedule

The 2026 program will occur in Utility Work Zones 10, 11, and 12.
Located north of Interstate 80 and east of Browns Valley Parkway.
Work will proceed zone by zone in numerical order.
Each zone will take approximately two (2) to four (4) weeks to complete
Only select hydrants and valves will be used in each zone.
Neighborhood signage will be posted where flushing is occurring.
Regular updates, including active work areas, will be posted here as well as on City social media and Nextdoor.

a utility work zoning map, highlighting the area located north of interstate 80 and east of Browns Valley Parkway

Current Hydrant Flushing Area

What is Hydrant Flushing?

Hydrant flushing involves opening fire hydrants to move large volumes of water through water mains at high velocity while exercising system valves. This process:

Removes sediment and mineral buildup; and
Improves water quality; and
Ensures hydrants and valves operate properly; and
Helps maintain fire protection and system reliability; and
Identifies potential storm drain issues such as blockages or breaks.

Although it may appear wasteful, flushing is a necessary and effective maintenance practice.

What Residents and Businesses May Experience

During flushing, customers in affected areas may notice:

Temporary reduced water pressure.
Temporary water discoloration.

Discoloration is caused by harmless sediment being stirred up and typically clears shortly after flushing is complete. The water continues to meet or exceed all state and federal drinking water standards.

Tips:

Check water clarity before doing laundry, especially whites.
Commercial businesses should plan for potential short-term water quality changes.

Drive carefully near work crews and open hydrants.

After Flushing: What to Do

If you notice discolored water:

Turn off the sink tap.
From the bathtub farthest from the front of your home, run cold water fully for several minutes.
Shut off the tub and check water clarity at the kitchen sink.
Repeat if needed; discoloration may last a few hours.

If water pressure seems low, check faucet aerators and washer screens for debris. If discoloration persists longer than 24 hours, contact the Utilities Department at (707) 469-6400.

Environmental Protection Measures

FAQs

Is it OK to drink sediment‐laden or discolored water after a nearby hydrant is flushed?

The water provided to your home is contained within a closed, chlorinated system, and is safe for human consumption. However, it is always recommended that water users take measures described above to flush the water system within your house to achieve clarity, or simply wait until the water has cleared naturally before using it for potable purposes.
What should I do after the flushing?

You could see some water discoloration at the tap due to hydrant flushing. If you encounter discolored water, close the sink tap. From the bathtub furthest from the front of your home, open the bathtub cold water valve fully and allow the water to run for several minutes and then shut the bathtub faucet off. Now from your kitchen sink faucet run cold water and check the clarity. If the water is still not clear, wait a few more minutes and check again. In some cases, you may experience slight discoloration for a few hours as your home water pipes continue to be flushed of the discolored water. This discoloration only affects the appearance of the water; it does not affect the taste or water quality.
What should I do if my water pressure or volume seems low after flushing?

Check your faucet and washer screens for trapped debris.
What should I do when I see city crews flushing hydrants in my area?

If you see a city crew flushing hydrants, please drive carefully.
When does flushing normally occur?

Normally, flushing takes place for approximately two months during early spring, starting mid-February. Flushing is done during daylight hours between 7:00 AM to 3:00 PM so staff can properly monitor the activity while maintaining the highest degree of safety while working in the roadway.
Why does the water system need to be routinely flushed?

The city’s water distribution system is a complex network of pipes and storage reservoirs where sediment or deposits may naturally accumulate over time. If not removed, these materials may cause water quality deterioration, taste and odor problems, or discoloration of the water. Water may also lose its chlorine residual in lesser used parts of the distribution system, resulting in degraded water quality. Flushing removes the “old” dechlorinated water, replacing it with fresh water. We refer to this as “turning over the water” in the system.
Why does the water look funny after hydrant flushing?

When a hydrant is opened, there will always be temporary incidences of discolored water containing fine sediment particles. There is no health hazard associated with discolored water. Allow a few hours for discoloration to dissipate. To verify the water has settled, allow your cold water tap to run a few minutes. If the discoloration persists for more than twenty‐four (24) hours, please contact our Utilities Department at (707) 469‐6400.

More FAQs

Vacaville, CA

I Want To...

How Do I...

What can we help you find?

City of Vacaville

Hydrant Flushing

FAQs