Is Ann Arbor, MI Tap Water Safe to Drink?
Graded D+ — but Chlorate was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
51.5/100
waterverge.com Ann Arbor, MI — Water Quality Report
Ann Arbor's drinking water received a grade of D+ (51.5 out of 100), indicating poor water quality. The city's 10 water systems serve approximately 279,046 residents using surface water.
Lead levels were measured at 7.2 ppb (90th percentile), which is within EPA limits but above recommended levels. UCMR 5 testing detected 4 PFAS compounds in the water supply.
The system has 94 violations on record, including 39 health-based violations. 21 remain unresolved.
What to know about Ann Arbor's water
Ann Arbor ranks #487 out of 520 cities in Michigan for water quality, placing it among the lowest-rated in the state.
The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.
PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.
Hexavalent chromium (chromium-6) was detected at 0.27 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
The system has seen 16 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Ann Arbor, MI water safe to drink?
Ann Arbor's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (51.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 10 water systems serve approximately 279,046 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Ann Arbor
A timeline of significant water quality events, violations, and data updates.
Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.
Latest EPA compliance and testing data incorporated into Ann Arbor's water quality assessment. Grade: D+ (51.5/100).
Contaminants: Lead and Copper Rule.
Contaminants: LEAD AND COPPER RULE REVISIONS, Consumer Confidence Rule.
Contaminants: E. COLI.
Federal disaster declaration (FEMA DR-3225). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Ann Arbor's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.
PFAS "forever chemicals" detected
UCMR 5 testing found 4 PFAS compounds in Ann Arbor's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.
Violation history
Ann Arbor's water system has 94 total violations on record, including 39 health-based violations. 21 remain unresolved. 16 violations were issued in the last 5 years.
Flood & environmental risk
Washtenaw County has experienced 2 federally declared disasters since 1980. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Mill Creek, Huron River, Allen Creek, Malletts Creek, Saline River.
Where does Ann Arbor's water come from?
Ann Arbor's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 10 water systems serving approximately 279,046 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Mill Creek (river), Huron River (river), Allen Creek (river), Malletts Creek (river), Saline River (river).
What Ann Arbor residents can do
Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Ann Arbor's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Forever chemicals overview
National PFAS report →Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Ann Arbor
Industrial polluters nearby
Reported releases to surface water by facilities near Ann Arbor, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
U.S. EPA NATIONAL VEHICLE & FUEL EMISSIONS LABORATORY ANN ARBOR, MI48105 | — | — | 2.1 mi |
CAYMAN CHEMICAL CO INC. ANN ARBOR, MI48108 | — | — | 3.2 mi |
CADILLAC ASPHALT LLC - ANN ARBOR ANN ARBOR, MI48103 | — | — | 3.5 mi |
SUPERIOR MATERIALS 38 ANN ARBOR, MI48103 | — | — | 3.5 mi |
DAPCO INDUSTRIES DEXTER, MI48130 | — | — | 8.2 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Ann Arbor
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- GELMAN SCIENCES INC3.5 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Washtenaw County has experienced 2 federally declared disasters since 1980. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Ann Arbor's water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 7.2 | 15 | ppb | Inorganic | Safe |
| 11Cl-PF3OUdS | ND | HI | µg/L | PFAS | Not Detected |
| 4:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 6:2 FTS 6:2 FTSPFAS A fluorotelomer sulfonate commonly found at sites contaminated with aqueous film-forming foam (AFFF) used in firefighting. Health EffectsPotential liver toxicity and endocrine disruption. Less studied but identified as a contaminant of concern. EPA LimitNo individual MCL (not yet regulated) Common SourcesFirefighting foam (AFFF), airports, military bases, and industrial facilities. | ND | HI | µg/L | PFAS | Not Detected |
| 8:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 9Cl-PF3ONS | ND | HI | µg/L | PFAS | Not Detected |
| ADONA | ND | HI | µg/L | PFAS | Not Detected |
| HFPO-DA HFPO-DA (GenX)PFAS A replacement for PFOA in manufacturing, marketed as safer but still a persistent "forever chemical." Also known as GenX. Health EffectsLiver and kidney effects, reproductive toxicity, immune system effects, and potential cancer risk. EPA Limit10 ppt MCL Common SourcesFluoropolymer manufacturing (used as PFOA replacement), industrial wastewater discharge. | ND | 0.01 | µg/L | PFAS | Not Detected |
| lithium LithiumInorganic A naturally occurring alkali metal found in groundwater. Monitored under UCMR 5 to assess occurrence in drinking water. Health EffectsKidney effects at high doses. Low-level exposure effects under study; some research suggests neurological effects. EPA LimitNo MCL (monitoring only under UCMR 5) Common SourcesNatural mineral deposits, geothermal water, and industrial discharge. | ND | HI | µg/L | PFAS | Not Detected |
| NEtFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| NFDHA | ND | HI | µg/L | PFAS | Not Detected |
| NMeFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| PFBA PFBAPFAS One of the shortest-chain PFAS compounds. Very mobile in water and difficult to remove with standard filtration. Health EffectsThyroid effects, potential developmental toxicity. Shorter half-life in body than long-chain PFAS. EPA LimitNo individual MCL (not yet regulated) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and firefighting foam. | 0.006 | HI | µg/L | PFAS | Detected |
| PFBS PFBSPFAS A short-chain PFAS used as a replacement for PFOS. While it clears the body faster than long-chain PFAS, it still persists in the environment. Health EffectsThyroid effects, reproductive and developmental toxicity, kidney effects. EPA LimitPart of Hazard Index (1.0) Common SourcesIndustrial discharge, firefighting foam, and as a replacement chemical in manufacturing. | ND | HI | µg/L | PFAS | Not Detected |
| PFDA | ND | HI | µg/L | PFAS | Not Detected |
| PFDoA | ND | HI | µg/L | PFAS | Not Detected |
| PFEESA | ND | HI | µg/L | PFAS | Not Detected |
| PFHpA PFHpAPFAS A medium-chain PFAS compound found in various environmental samples. Less studied than PFOA/PFOS but still considered a contaminant of concern. Health EffectsLiver effects, potential developmental toxicity, and endocrine disruption. EPA LimitPart of Hazard Index (1.0) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and contaminated water sources. | 0.004 | HI | µg/L | PFAS | Detected |
| PFHpS | ND | HI | µg/L | PFAS | Not Detected |
| PFHxA PFHxAPFAS A short-chain PFAS replacement chemical widely used after manufacturers phased out longer-chain PFAS. Very commonly detected in water. Health EffectsLiver and kidney effects, potential thyroid disruption. Considered less toxic than long-chain PFAS but still persistent. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial processes, firefighting foam (AFFF), food packaging, and textile treatment. | 0.004 | HI | µg/L | PFAS | Detected |
| PFHxS PFHxSPFAS A medium-chain PFAS found in firefighting foam and consumer products. It has a long half-life in the human body, similar to long-chain PFAS. Health EffectsImmune system effects, thyroid disruption, and potential reproductive and developmental harm. EPA LimitPart of Hazard Index (1.0) Common SourcesFirefighting foam (AFFF), waterproof textiles, food packaging, and industrial discharge. | ND | HI | µg/L | PFAS | Not Detected |
| PFMBA | ND | HI | µg/L | PFAS | Not Detected |
| PFMPA | ND | HI | µg/L | PFAS | Not Detected |
| PFNA PFNAPFAS A long-chain PFAS compound used in manufacturing fluoropolymers. It bioaccumulates in the body and is very persistent in the environment. Health EffectsDevelopmental effects, liver toxicity, immune suppression, and potential cancer risk. EPA LimitPart of Hazard Index (1.0) Common SourcesFluoropolymer manufacturing, industrial emissions, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFOA PFOAPFAS A long-chain PFAS ("forever chemical") once widely used in nonstick coatings and firefighting foam. It persists in the body and environment for years. Health EffectsLinked to kidney and testicular cancer, thyroid disease, elevated cholesterol, and reproductive issues. EPA Limit4.0 ppt MCL Common SourcesIndustrial discharge, firefighting foam (AFFF), nonstick cookware manufacturing, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFOS PFOSPFAS A long-chain PFAS compound historically used in stain-resistant coatings and firefighting foam. One of the most studied and persistent PFAS chemicals. Health EffectsLiver damage, immune system suppression, thyroid disruption, increased cholesterol, and potential cancer risk. EPA Limit4.0 ppt MCL Common SourcesFirefighting foam (AFFF), industrial sites, stain-resistant fabric treatments, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFPeA PFPeAPFAS A short-chain PFAS compound commonly detected in drinking water. One of the most frequently found PFAS in UCMR 5 monitoring. Health EffectsLess studied than PFOA/PFOS. Potential liver and thyroid effects. Research is ongoing. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial discharge, firefighting foam degradation, and consumer products. | 0.005 | HI | µg/L | PFAS | Detected |
| PFPeS | ND | HI | µg/L | PFAS | Not Detected |
| PFTA | ND | HI | µg/L | PFAS | Not Detected |
| PFTrDA | ND | HI | µg/L | PFAS | Not Detected |
| PFUnA | ND | HI | µg/L | PFAS | Not Detected |
Lead level trend (90th percentile)
See how Ann Arbor compares by contaminant
Explore where Ann Arbor ranks among all Michigan cities for specific contaminants.
Water source & infrastructure
Where Ann Arbor's water comes from
Ann Arbor's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.
These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.
The system is operated by local government ownership and serves approximately 279,046 people through 10 water systems.
Water bodies near Ann Arbor
Ann Arbor is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Ann Arbor
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ANN ARBOR | MI0000220 | 241,868 | SW |
| PITTSFIELD TOWNSHIP | MI0005360 | 24,500 | SWP |
| SCIO TOWNSHIP | MI0005977 | 8,500 | SWP |
| LOCH ALPINE SANITARY AUTHORITY | MI0003940 | 1,506 | GW |
| ANN ARBOR TOWNSHIP | MI0000221 | 1,338 | SWP |
| BARTON HILLS | MI0000430 | 450 | GW |
| SALINE VALLEY FARMS | MI0005901 | 375 | GW |
| WHITMORE LAKE APARTMENTS | MI0007101 | 281 | GW |
| COPPER MEADOWS | MI0001631 | 128 | GW |
| SISTERS OF MARY, MOTHER OF EUCHARIST | MI0006074 | 100 | GW |
How Ann Arbor compares
Full Michigan rankings →Ann Arbor's score of 51.5/100 is below the average of 72/100 among major Michigan cities. It outscores 2 of 10 nearby cities. 8 of 10 nearby cities score higher.
Nearby cities
View Michigan rankings →About Ann Arbor, MI
Wikipedia →Ann Arbor is a city in Washtenaw County, Michigan, United States, of which it is the county seat. It had a population of 123,851 in 2020, making it the fifth most populous in Michigan.
Learn more about your water
Guides and resources related to Ann Arbor's water quality findings.
Explore water quality across Washtenaw
Frequently asked questions
Is Ann Arbor, MI tap water safe to drink?
Ann Arbor's water quality earned a grade of D+ (51.5/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #487 out of 520 cities tested in Michigan.
What contaminants are in Ann Arbor's water?
Lead was measured at 7.2 ppb (90th percentile). 4 PFAS compounds were detected. 94 violations are on record.
How is Ann Arbor's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Ann Arbor?
While lead levels are within EPA limits, a filter adds extra protection. PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.
Where does Ann Arbor's water come from?
Ann Arbor's water is sourced from Surface water. The city has 10 water systems serving approximately 279,046 residents.
What health violations has Ann Arbor's water system had?
Ann Arbor has 39 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 21 violations remain unresolved.
Why does Ann Arbor have so many PFAS compounds in its water?
4 different PFAS "forever chemical" compounds were detected in Ann Arbor's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. While detected, current levels are within EPA limits. An activated carbon filter can further reduce exposure.
How does Ann Arbor's water compare to other cities?
Ann Arbor ranks #487 out of 520 cities in Michigan (better than 6% of state cities) and #12862 out of 15744 cities nationally (18th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.