Water Treatment

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​​​Ann Arbor Water Logo

​​​​ 919 Sunset Road, Ann Arbor, MI 48103

8 a.m.-5 p.m.
(excluding holidays)

24/7 water emergency line



Molly Maciejewski,
Water Treatment Services Manager


Qu​​​ick Links 

Monthly Water Quality Dashboard​

​Our qualified staff of water utility professionals are dedicated to providing our customers with the best quality drinking water possible and we continue to meet or produce better quality water than State and Federal regulations require. We operate seven days a week, 365 days a year and conduct approximately 15,000 tests per month for more than 100 contaminants. Some recent results are included below. 


​Water Quality Dashboard testing timeline 

Our monthly water quality dashboard shows the most recent month of available results. Testing for PFAS and 1,4-dioxane is completed by a subcontract lab with specialized instrumentation and experienced staff, so results can take a month or more to be provided to us. City of Ann Arbor uses multiple lines of defense against each type of contaminant, and we monitor each treatment step closely using both real-time performance indicators and longer term testing of specific contaminants. This strategy allows us to keep your water safe from contaminants that can be analyzed quickly as well as those that require more time and specialized instrumentation.​

If you have any specific concerns or water quality questions, we look forward to answering them. Staff can be reached at 734.994.2840 or via email [email protected]. ​​

Fire Hydrant Flushing​

The City of Ann Arbor conducts annual fire hydrant flushing beginning every spring and continuing on a weekly basis through the fall.​​​

Hydrant flushing is part of the City's annual maintenance and done to remove minerals and ​sediment that accumulate in the water lines over the course of a year. This preventative maintenance also allows us to check and record water pressure to ensure the water system is functioning properly. On occasion, the water in your home or businesses may have an orange or rusty appearance. The water is safe to use and drink, but it can cause stains to laundry if the discoloration is not first cleared from the lines. If this occurs, products like “Rover" can help remove temporary laundry coloration. The water discoloration is being caused by iron sediment in the water main being disturbed by the hydrant flushing. If this occurs, please run your COLD water for several minutes and flush your toilet to clear your lines. Please do not run hot or warm water, as this forces the discolored water into the water heater, mixing it with clear stored water. If you do get rusty water in your hot water tank, it is necessary to drain the hot water tank per the manufacturer's instructions.

To view the areas currently hydrant flushing, as well as those on the schedule to flush next, see the Hydrant-flushing map.