Hydrant and Water Heater Flushing

Hydrant Flushing

Twice a year (spring and fall), the City of Fridley flushes out its water mains through the fire hydrants. The purpose of flushing the water lines is to clear the water mains of small amounts of sediment like iron or manganese that settles in water mains over time. We also verify that the hydrants are in good working order.

After flushing of the City's mains is completed, we suggest that you flush your hot water heater, which can accumulate sediment over time. 

During flushing, deposits from water lines may create a yellowish to brownish discoloration of water in homes near flushing areas. While this water is safe for drinking, it may discolor laundry. If this discoloration last longer than two days, residents are asked to call the City's Public Works Department at (763) 572-3566. Resident may also call Public Works to get current flushing locations and updated information.


Water Heater Flushing

Each year after the spring water main flushing program has been completed, we suggest residents flush their hot water heaters. Many types of sediment such as iron, magnesium and calcium may build up in the bottom of your hot water heater, causing discoloration or rust in the hot water taps. (Calcium appears as sand particles in the hot water system.) In most cases, flushing the hot water heaters can eliminate this. Listed below is a simple procedure you can follow to flush your hot water heater:

  1. Turn the water off at the water meter.
  2. Turn gas heaters down to “pilot” or electric heaters to the “off” position.
  3. Hook up a water hose to the tank drain outlet at the bottom of the water heater and place the other end of the hose by the floor drain.
  4. Open a hot water tap at the laundry tub to allow air into the hot water pipes.
  5. Open the hot water heater faucet and allow tank to drain completely.
  6. Once the tank has drained, turn the water back on by the meter. Let the tank fill until the water begins flowing out of the hose at the drain.
  7. Allow the water to flow through the tank for 2 to 3 minutes, then shut the water off at the meter and allow the tank to drain out completely once again.
  8. Repeat steps 6 and 7 until water flows clean at the drain.
  9. Once the water flows clean again, shut the drain faucet off at the bottom of the hot water tank and remove the hose.
  10. Turn the gas or electric heater controls back to the “normal” or “on” positions. Also be sure to turn the water back on at the meter to allow refilling of the tank and proper operation of your water system throughout your residence.
  11. Open all hot water taps throughout the residence to flush out all sedimentation that may have become agitated throughout the hot water pipes during the tank flushing. Close all taps as the water flow clears.
By following these steps, not only will the hot water tank be cleaned out, but also the heater will run more efficiently and help conserve energy.