Hydrant Flushing

Hydrant Flushing Operations

Annual hydrant-flushing is an important part of domestic water distribution system maintenance. Each year Maintenance Division utility crews systematically open hydrants throughout the City to allow water to flow at high velocity through distribution mainlines. This operation serves the following purposes:
  • Enhances water quality by removing sediments from inside the mainline and flushing them out through the hydrant.
  • Identifies malfunctions of hydrants and related valves.
  • Helps determine weaknesses in the water distribution system.
  • Identifies inadequate water volume and pressure in mainlines.
  • Helps determine fire flow at the hydrant. 
You may encounter the following conditions during hydrant flushing operations:
  • A temporary drop in the water pressure to your home or business.
  • Rusty brown or cloudy water. Discolored water is not harmful; these conditions will subside a few hours after flushing is completed.
Helpful information to remember after the flushing operation is complete:
  • Open the cold water faucets and let the water flow until it is clear. Turn off the faucets.
  • Open the hot water faucets and let the water flow until it is clear. Turn off the faucets.
  • When both hot and cold water are clear, the water is ready for use as normal.
  • Check the faucet screens for trapped particles.


Q: Why does my water look rusty or cloudy after hydrant flushing?
When a hydrant is opened, the water in the mainline will flow out at a high velocity. This creates a scouring action in the pipe and dislodges fine mineral particles that have accumulated in the pipe. The fine sediment mixes with water which can turn it a cloudy or rusty brown color. This mixture is discharged out of the hydrant. There is no health hazard associated with the discolored water. Remember, after the hydrant flushing operation, let your water clear before you use it.

Q: What should I do when City crews are flushing hydrants in my area?
If you are driving in the work zone, please slow down and drive carefully.

Q: Who do I call for more information?
For additional information about hydrant flushing, please call the Maintenance Division at (503) 873-6359.
  1. Maintenance Division

    Physical Address
    City Shops
    830 McClaine Street
    Silverton, OR 97381

    Phone: 503-873-6359