Last night I opened the cold water on my faucet to fill a pot to make some ramen. Right as I was about to put my pot under the faucet the water turned brown and there was a noticeable pressure drop so I turned the faucet off.
Remembering a similar biyearly occurrence at a previous residence (every time they'd flush/check the fire hydrants), I assumed it might be rust that had clogged the airator screen. I removed the handle off of my faucet head and started to flush water into the sink. The water was clearer than before but it was still darker color than normal. After about 2 min it started looking more normal, then suddenly started expelling the large chunks, some as long as 4 cm pictured below.
Does anyone know what these are? Was this created by bacteria? rusting pipes? lime scale?
I called my utility to ask what was happening, they told me there was no work in my area, or hydrants being flushed and to just flush from the lowest point in my house. I did that but only saw a couple flakes which could of just been Teflon threading from the removal of the shower handle there. I went back up stairs to finish flushing my kitchen sink, but it took more than 20 min of shutting off and turning back on my cold water for the flakes to subside.