Water Service Line Flushing

Discolored water is typically caused by sediment, such as iron. Although discolored water is not aesthetically pleasing it is not unsafe* and can easily be resolved by flushing the service line. Flushing allows a larger than normal quantity of water to flow through the service line, allowing it to be cleansed. If your water is discolored, we recommend avoiding the use of hot water** until the cold water is clear.


Water Service Line Flushing Instructions

*DO NOT FLUSH YOUR LINES UNLESS ADVISED BY HAWC*

Outdoor Flushing:
(Should an outside faucet not be available; flush the system using inside faucets.)

1. Remove any hoses and/or sprinklers
2. Turn on the water at all outside water faucets simultaneously
3. Let water flow for approximately 10-15 minutes (or until running clear)

Indoor Flushing:

1. Remove any aerators and water filters from faucets/fixtures
2. Turn on the COLD WATER ONLY for all faucets (i.e. sinks, tubs, showers, etc.) simultaneously
3. Let water flow for approximately 10-15 minutes (or until running clear)

You may notice the discoloration returns after the water has sat in the lines for a period of time, such as overnight or during the day if it’s not being used – this is to be expected. When the water is not used for a longer period of time the sediment settles, when water is turned on the sediment is agitated and will return. If this happens you may repeat the flushing process.


*Some people may be more vulnerable to contaminants in drinking water than the general population. These people should seek advice about drinking water from their health care providers.

** If you have used hot water prior to flushing the water heater may need to be flushed as well, refer to the manufacturer’s manual for instructions or contact a licensed plumber.


Questions on Water Quality?
Click here to view a copy of the most recent Water Quality Report for your water system.