Is Onsted, MI Tap Water Safe to Drink?
Graded B+, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
83.2/100
waterverge.com Onsted, MI — Water Quality Report
Onsted's drinking water received a grade of B+ (83.2 out of 100), indicating good water quality. The city's 1 water system serves approximately 907 residents using groundwater.
Lead levels were measured at 4.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 8 violations on record, including 0 health-based violations. 3 remain unresolved.
What to know about Onsted's water
Onsted ranks #302 out of 520 cities in Michigan for water quality, placing it below average in the state.
Onsted relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Onsted may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Onsted, MI water safe to drink?
Onsted's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 907 residents using groundwater (wells).
Recent water quality updates for Onsted
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Onsted's water quality assessment. Grade: B+ (83.2/100).
Contaminants: Revised Total Coliform Rule.
Contaminants: LEAD AND COPPER RULE REVISIONS.
Contaminants: Lead and Copper Rule.
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 Onsted's water supply.
Well within EPA limits.
Violation history
Onsted's water system has 8 total violations on record, including 0 health-based violations. 3 remain unresolved. 4 violations were issued in the last 5 years.
Flood & environmental risk
Lenawee County has experienced 1 federally declared disaster since 2005. 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 S Branch River Raisin.
Where does Onsted's water come from?
Onsted's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 907 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include S Branch River Raisin (river).
What Onsted residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Onsted'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 ↓Violation summary
Violations & advisories
Flood & disaster history
Lenawee County has experienced 1 federally declared disaster since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 4.0 | 15 | ppb | Inorganic | Safe |
Lead level (90th percentile)
Latest reading: 4.0 ppb (2024)
EPA action level: 15 ppb
See how Onsted compares by contaminant
Explore where Onsted ranks among all Michigan cities for specific contaminants.
Water source & infrastructure
Where Onsted's water comes from
Onsted's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 907 people through 1 water system.
Water bodies near Onsted
Onsted is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Onsted
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ONSTED | MI0005020 | 907 | GW |
How Onsted compares
Full Michigan rankings →Onsted's score of 83.2/100 is above the average of 70/100 among major Michigan cities. It outscores 5 of 10 nearby cities.
Nearby cities
View Michigan rankings →About Onsted, MI
Learn more about your water
Guides and resources related to Onsted's water quality findings.
Explore water quality across Lenawee
Frequently asked questions
Is Onsted, MI tap water safe to drink?
Onsted's water quality earned a grade of B+ (83.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #302 out of 520 cities tested in Michigan.
What contaminants are in Onsted's water?
Lead was measured at 4.0 ppb (90th percentile). 8 violations are on record.
How is Onsted'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 Onsted?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Onsted's water come from?
Onsted's water is sourced from Groundwater. The city has 1 water system serving approximately 907 residents.
Is Onsted's groundwater at risk of contamination?
Onsted uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 8 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Onsted's water compare to other cities?
Onsted ranks #302 out of 520 cities in Michigan (better than 42% of state cities) and #6560 out of 15744 cities nationally (58th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Onsted's small water system affect quality?
Onsted's system serves approximately 907 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 8 violations on record.