FAQ: How To Flush Water Lines And Appliances

BOSTON — On Tuesday morning, Gov. Deval Patrick lifted the boil-water order that had been in effect since a 10-foot water pipe burst on Saturday. But before water is safe to drink, the Massachusetts Water Resources Authority has advised residents to “flush” their water in order to clear plumbing of potentially contaminated water. This includes interior and exterior faucets, showers, water and ice dispensers, water treatment units and more.

Guidelines For Flushing Your Water System

Cold Water Faucets: Run tap water until the water feels cold — typically for at least one minute — before drinking, tooth brushing or using for food preparation.

Hot Water Faucets: To clear hot water pipes and water heaters of untreated water, turn on all hot water faucets and flush for a minimum of 15 minutes for a typical household 40-gallon hot water tank and 30 minutes for an 80-gallon hot water tank or larger. Never use water from the “hot” faucet for drinking, cooking or other internal-consumption purposes. After this flushing, hot water is safe to use for washing hands, and for handwashing of dishes, pots and pans, etc.

Refrigerators: Water dispensers from refrigerators should be flushed with at least a quart of water.

Dishwashers: After flushing hot water pipes and water heater, run dishwasher empty one time.

Humidifiers: Discard any water used in humidifiers, Continuous Positive Airway Pressure (CPAP), oral, medical or health care devices, and rinse the device with clean water.

Food and baby formula:
Be sure you have discarded any baby formula or other foods prepared with water on the days of the boil order. (If unsure of the dates, contact your water department.) This includes drinks such as Gatorade made with powder or concentrate.

Ice cubes: Automatic ice dispensers should be emptied of ice made during the boil order. Then, discard ice made over an additional 24-hour period to assure complete purging of the water line.

Water filters: Clean or change your water filter, or contact the filter manufacturer for more details.

Water supplies for pets: Pet owners should follow the same protocol for their pets’ water supply as they would for themselves, which means flushing out their water systems before serving tap water to an animal. Contact your veterinarian if you think your pet is ill due to drinking contaminated water.

Due to the flushing-out of taps, water mains and fire hydrants, some residents may experience a lack of water pressure and/or discolored water. However, this is an expected result and does not pose a health risk, according to Fred Laskey, the MWRA’s executive director.

“That increased rate of flow will sometimes loosen up some rust that may have built up on the side of the pipe. That’s the discoloration. That’s safe. You can run it till your tap comes clear. But that’s not any indication of any organic matter in there that may cause problems with your stomach or anything like that.”

Fred Laskey, Massachusetts Water Resources Authority

State officials also said that more than 90 percent of the tap water that had been flowing to affected communities during most of the boil-water order was actually treated, greatly reducing the chance that anyone will become sick from having consumed contaminated water.

State officials said water from the emergency reserves that were tapped during the crisis had been treated with a larger-than-usual amount of chlorine, and then blended with treated water from the regular MWRA system. That combination meant that any water containing potentially harmful organisms was heavily diluted, helping protect public health.

Any lingering chlorine smell does not pose a health risk, Laskey said.

Contact your local water department if you have additional questions.

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  • Jon Crocker

    Under the rubric of “water conservation” it would have been nice if the instructions for post-boil water order would have asked people to bathe for 15 minutes using their warm water pipes this morning, instead of running their taps for 15 minutes. I cringe to think of hundreds of thousands of households each dumping 40 to 80 gallons of water because they were instructed to, without the helpful reminder of useful suggestions as to how to USE this precious resource, not waste it.

  • Jeffrey Schnitzer

    I cringe at the water bill. Exactly who is supposed to pay for all this waste?

  • Jeffrey Schnitzer

    I mean the aggregate bill. Why should consumers pay for a provider’s problem ot possible error?

  • Emily E.

    I am a senior citizen on fixed income. It would be a wonderful gesture if everyone got a break on the next water bill – even though some of us seniors get a small discount. The general public received a letter some time ago stating that the MWRA made an error in billing and that an increase would show up in the next bill. My bill increased substantially.
    Thank you.

  • vicki moran

    Would also recommend that people clearing their pipes do a load of whites in hot water first before running the hot taps to clear out their water heaters. Then fill as many containers as they possibly can, and use that water once it cools on the garden, or their indoor plants. Every little bit helps!!!

  • Roxanne

    Just one recommendation. The filter inside our faucets were full of soil and probably contaminated from the old water running still running now.

    People should twist open their little filter attached to every simple faucet or the big ones as well, and clean and disinfect. The little filters attached inside your faucets (all come with it) were full of soil this morning – so much so that the water was barely coming out.

    When I took it out, the water without the filter came out brown. Yes, very brown and full of soil! So take care. Because if you drink from it you might get sick and then people will say “they” rushed to lift the water boil – and in reality – that is not the problem. The next work starts with us at home. OUR pipes at home.

    And Thank your for the governor for attacking this head-on and fast.

  • Lee Mondale

    To add to the message by Jon Crocker:
    I don’t think we need to purge showers, since we were advised that we could take them during the emergency-consider the shower as part of the purge. Of course,I wouldn’t want to shower, should the water turn brown. I’m planning to purge the other faucets first to lessen the brown water to showers.
    Lee Mondale

  • Kathy Sharkey

    Good to know.

  • John Smith

    If we flush the system in the house what about the pipes in the street >? If they were infected wouldn’t they just keep giving us contaminated water until they were completely flushed all the way back to the source of the bad water ??

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