Light yellow to dark brown water is typically caused by a disturbance of pipeline sediments in the water main. The discoloration is caused by dissolved iron which is stirred up in naturally-occurring sediments that exist in all water systems. Any of the following circumstances may have caused flow reversals in the water mains and sediment to be disturbed.

• The different colors can be attributed to varying chemical oxidation states of the iron (or rust) and by varying concentrations of the rust in the water.
• The discolored water may be due to planned cleaning of the water main to remove pipeline sediments in your area.
• A nearby water hydrant may have been knocked over due to a vehicle collision or may be in use to fight a fire.
• There may be some pipeline repair work (or construction activity) in the area and some valves may have been closed for this work.

Despite its appearance, this does not indicate that the water is unsafe or that the integrity of the water main has been compromised. A disinfectant residual is maintained at all times to ensure that the water is safe for household use, including cooking and drinking. For aesthetic reasons, you should avoid doing laundry until the water clears up.