City of Coon Rapids issued the following announcement on April 7.
Crews began flushing fire hydrants in the west side of the city this week. The flushing is part of an important annual maintenance process, which cleans sediment and stagnant water from the City's pipe system. Similar flushing in the east side of the city occurred last spring.
During the next few weeks, crews will work throughout the area of the city southwest of Highway 10.
Brown Water - Please be aware that hydrant flushing can cause some temporary water discoloration. Flushing the watermain causes a disruption in the directional flow of the water, which stirs up sediment in the system. This sediment includes iron, which leads to the brown color. The flushing process should push that sediment out of the pipes and result in clearer water overall.
While brown water may be unsightly, it is safe to drink. Residents who notice brown water from the faucet may want to avoid washing clothes. The discoloration should pass within a few days. Water softeners also help remove the discoloration.
Original source can be found here.