I had to call the plumber to come out a few times recently to work on my kitchen faucet or bathroom faucet. Each time, he either turned off the water under the sink or turned off the water to the house. The funny thing is each time he turned the water back on, it seemed like there was sediment that came out and was caught in my kitchen sprayer or in the bathroom faucet aerator.
This is confusing to me since we didn't dig the pipe up to introduce dirt into the water system or anything. All that was done was turn the valve underneath the sink a half turn to shut off water or allow water. Can someone explain to me what's happening and why sediment gets disturbed when I turn the underneath valve?


