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reduced water pressure after shutoff

The water company recently shut off my water for repair work in the neighborhood. After the water came back on, water pressure in certain faucets and the shower were significantly reduced and large white particles of what appear to be mineral deposits show up in the water and strainers of the drains. What caused this and what can I do to correct it? The water company tested the water agreed that pressure was low and said the test results show the water is safe.

Blue RidgeParkway
Re: reduced water pressure after shutoff

Were you affected by that horendous water main break that made it on national news with its raging rapids river flooding? wow that sure was a mess huh?

If the city agrees they are providing less water pressure now that might be the issue, if you have a pressure reducing device might need adjustment. If the old pressure was very high instead of a PRV might have had plumbing oversized on the exit of the meter to reduce pressure and now if pressure at the city main is lower, might be too. Might also be reduced pressure and flow further complicated by sediment stirred up in the event, and continuing to crumble and pass through due to lower pressure now and sudden change (temporarily) in the water chemistry of what is being supplied (imagine they dumped a LOT of chlorination products to treat the system after repair to counteract contamination), has caused the lining of sediment/mineral scale to bust up from the mains, and even your own plumbing, flowed through and has clogged up your plumbing an/or plumbing fixtures.

Imagine the lack of water in the mains plus restoring water and pressure would easily be enough on its own to cause mineral scale built up on the lines for the mains over many years to crumble and when water restored flushed a lot of sediment into your local mains and into the house. Same effect could have happened within house plumbing.

Sediment. remove faucet areator & screen assemblies, clean and reinstall, same for shower head aerator assembly.

If still problem disconnect lines from shut off valves and open valve to a bucket see if valves are clear of sediment, if clear then narrow down to supply lines and/or valves/cartridge/mixer body in faucet might need to be flushed.

Other areas might be affected: pressure reducing/regulating valve might need screen flushed, water heater tank might need flushing from sediment. if still problem might need to reverse flush plumbing lines of sediment.

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