WaterVerge

Is Chelsea, MI Tap Water Safe to Drink?

Graded B — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

6K residents served 3 water systems PWSID: MI0001370
Overall Score
76.1 / 100
Violations
6 active
Last Updated
May 2026
Source
Groundwater
#397 of 520 in Michigan Top 60% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
76.1/100
waterverge.com
B 76.1/100

Chelsea, MI — Water Quality Report

Chelsea's drinking water received a grade of B (76.1 out of 100), indicating good water quality. The city's 3 water systems serve approximately 5,793 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 19 violations on record, including 10 health-based violations. 6 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Chelsea's water

Chelsea ranks #397 out of 520 cities in Michigan for water quality, placing it among the lowest-rated in the state.

Chelsea 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.

The system has seen 7 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
76.1 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
32.1/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 0.0 ppb (90th percentile).
Contaminants
18/20
A
No PFAS compounds detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Chelsea, MI water safe to drink?

Concerns Identified

Chelsea's drinking water has significant quality concerns based on EPA testing data. With a grade of B (76.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 5,793 residents using groundwater (wells).

6
Active Violations
0.0 ppb
Lead (90th %ile)
None
PFAS Detected
2 events
Disaster History

Recent water quality updates for Chelsea

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Chelsea's water quality assessment. Grade: B (76.1/100).

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Arsenic.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Arsenic.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3225). Hurricane event — may have impacted local water infrastructure.

Disaster
SEVERE STORMS & FLOODING

Federal disaster declaration (FEMA DR-631). Flood event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Chelsea's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 1.74 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

Violation history

Chelsea's water system has 19 total violations on record, including 10 health-based violations. 6 remain unresolved. 7 violations were issued in the last 5 years.

RPTMCLMONMROtherTT
Most recent violations:
Dec 2024 Revised Total Coliform Rule Open
Oct 2023 Arsenic Resolved
Jul 2023 Arsenic Resolved
Apr 2023 Arsenic Resolved
Jan 2023 Revised Total Coliform Rule Resolved

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, River Raisin.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3225
SEVERE STORMS & FLOODING
Flood FEMA DR-631

Where does Chelsea's water come from?

Chelsea's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 5,793 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Mill Creek (river), River Raisin (river).

What Chelsea residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Chelsea's water.

Request your utility's CCR

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.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.74 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
0
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

19
Total violations
10
Health-based
6
Active / unresolved
Dec 2024
Most recent violation
Compliance Record

Violations & advisories

19 Total
6 Active
10 Health-based
13 Resolved
Violations by category
Arsenic Rule
5
Total Coliform Rule
5
Consumer Confidence Rule
3
Revised Total Coliform Rule
2
Volatile Organic Chemicals
1
Dec 2024 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Jul 2020 Active
Consumer Confidence Rule
Other Violation 0
Nov 2016 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2005 Active
Consumer Confidence Rule
Other Violation 0
Jul 2005 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2023 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Dec 2023
Jul 2023 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Sep 2023
Apr 2023 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Jun 2023
Jan 2023 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Jan 2023
Jan 2023 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2023
Jul 2022 Resolved
Styrene
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2022
Mar 2006 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2006
Jan 2006 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2008
Jun 2003 Resolved
Acrylamide
Treatment Technique
Health-Based Health Resolved May 2004
Jun 2000 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jun 2000
Aug 1996 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 1996
Aug 1995 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 1995
Oct 1993 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Oct 1993
Industrial pollution

Top industrial polluters within 10 miles of Chelsea

Industrial polluters nearby

Reported releases to surface water by facilities near Chelsea, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
ABRASIVE FINISHING INC
Nonmetallic Mineral Product · NA
CHELSEA, MI48118
3.0 mi
DAPCO INDUSTRIES
Fabricated Metals · DAPCO INDUSTRIES
DEXTER, MI48130
7.3 mi
DEXTER FASTENER TECHNOLOGIES INC
Fabricated Metals · DEXTER FASTENER TECHNOLOGIES INC
DEXTER, MI48130
7.3 mi
ALPHA METAL FINISHING CO.
Fabricated Metals · ALPHA METAL FINISHING CO
DEXTER, MI48130
7.2 mi
ALCO MANUFACTURING CORP LLC
Fabricated Metals · ALCO HOLDINGS
DEXTER, MI48130
6.0 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

2
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

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.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3225
Sep 1980
SEVERE STORMS & FLOODING
Flood FEMA #631

Recommended water filters

Based on contaminants detected in Chelsea's water supply, we recommend the following filter types.

🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.74 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS 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 ND 0.01 µg/L PFAS Not Detected
lithium 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 ND HI µg/L PFAS Not Detected
PFBS 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 ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not 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
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.5 ppb from 1992 (2.5 ppb) to 2024 (0.0 ppb).

Copper level trend (90th percentile)

EPA action level: 1.3 mg/L
Copper has decreased by 1.102 mg/L from 1992 (2.840 mg/L) to 2005 (1.738 mg/L).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
5,793
Water Systems
3
Water Source

Where Chelsea's water comes from

Groundwater

Chelsea'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 5,793 people through 3 water systems.

Local Hydrology

Water bodies near Chelsea

Chelsea is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Mill Creek
river
River Raisin
river
Infrastructure

Water systems serving Chelsea

System Name PWSID Population Source
CHELSEA MI0001370 5,474 GW
SYLVAN TOWNSHIP MI0006531 263 GW
ST. LOUIS CENTER MI0006325 56 GW
Regional Comparison

How Chelsea compares

Full Michigan rankings →

Chelsea's score of 76.1/100 is above the average of 70/100 among major Michigan cities. It outscores 5 of 10 nearby cities.

Chelsea (this city)
76.1
Detroit
84.1
Ann Arbor
51.5
Lansing
57.3
Michigan avg
70
City Profile

About Chelsea, MI

Economic Profile
$71,379
Median Income
$290,858
Median Home Value
$1,564/mo
Median Rent
1.3%
Unemployment
Community
50.1
Median Age
581
People / sq mi
49.1%
College Educated
63.7%
Homeownership
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Frequently asked questions

Is Chelsea, MI tap water safe to drink?

Chelsea's water quality earned a grade of B (76.1/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #397 out of 520 cities tested in Michigan.

What contaminants are in Chelsea's water?

Lead was measured at 0.0 ppb (90th percentile). No PFAS compounds were detected. 19 violations are on record.

How is Chelsea'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 Chelsea?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Chelsea's water come from?

Chelsea's water is sourced from Groundwater. The city has 3 water systems serving approximately 5,793 residents.

What health violations has Chelsea's water system had?

Chelsea has 10 health-based violations on record. The most recent violation was recorded in December 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 6 violations remain unresolved.

Is Chelsea's groundwater at risk of contamination?

Chelsea 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 19 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 Chelsea's water compare to other cities?

Chelsea ranks #397 out of 520 cities in Michigan (better than 24% of state cities) and #9387 out of 15744 cities nationally (40th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.