Flushing
Flushing the water mains improves water quality by removing sediment that slowly builds up at the bottom of the water main over time.
How it Works
During a flushing operation in your neighborhood, you’ll see crews flushing via fire hydrants. Flushing will generally occur Monday-Thursday, between 8:00 AM and 3:30 PM for most neighborhoods. During the flushing process, water is forced through the water mains at a high speed and discharged through hydrants. The fast-moving water scours and cleans the mains, improving the overall quality of water in the distribution system. YLWD leaves the hydrants open until the water runs clear.
Water Discoloration
Water is sometimes discolored after water main cleaning, but this should not last long.
What to Do About Discoloration
In the event you draw discolored water into the home, flush a cold tap for a few minutes, for up to 15 minutes maximum.
- Do NOT choose a tap that has a water filter connected to it, or the sediment may clog your filter.
- Do NOT use a hot water tap because it could draw sediment into your hot water tank.
- Avoid washing clothes while flushing is occurring in your area.
When to Call YLWD
If your water is still discolored after three to four hours, contact YLWD at 714.701.3000.

Flushing FAQ
Is water main cleaning a waste of water?
No, this is a normal and necessary part of maintaining a safe and reliable drinking water supply. If water is discharged into the environment, it will soak back into the groundwater basins for reuse.
Do other cities have similar water main cleaning programs?
Many cities have some type of flushing program to clean their water mains. Flushing is commonly considered to be a great way to improve water quality and increase the reliability of the water distribution system.
What about water pressure and safety?
Flushing may cause short-term pressure fluctuations along with
sediments in the water reaching your home or business, try to not use water during this time. Your water remains safe, meeting if not exceeding all water quality standards.