Arsenic in Drinking Water in Michigan
What residents of Michigan need to know about arsenic in drinking water — including natural geological sources, private well risk, which utilities have documented violations, and how to remove arsenic from tap water.
Source: EPA SDWIS, Michigan Department of Environment, Great Lakes, and Energy, USGS · Last reviewed: 2025-01-01
Quick Answer
Is arsenic in drinking water a concern in Michigan?
Yes. Michigan has documented arsenic in glacial aquifer systems across the southern Lower Peninsula, in the glacial sand-and-gravel aquifers that are the primary source of private well water for millions of Michigan residents. Michigan EGLE has documented arsenic occurrence in private wells in numerous counties, and the state has one of the most active private well arsenic assessment programs in the country.
Where does arsenic come from in Michigan's water?
Glacial aquifer geology — outwash sands and gravels, buried valley deposits, and glacial till — is the dominant arsenic pathway in Michigan's Lower Peninsula. Arsenic occurs naturally in mineral sediments and mobilizes under reducing geochemical conditions common in deep aquifer environments. The southern Lower Peninsula counties of Allegan, Kent, Barry, Ionia, Montcalm, and Newaygo have documented elevated arsenic in private well surveys.
What should Michigan residents know?
Michigan EGLE has conducted one of the most comprehensive private well arsenic surveys in the country, identifying arsenic as a priority concern for private well owners across the Lower Peninsula. The state strongly recommends private well testing for arsenic. Michigan EGLE provides subsidized testing for low-income residents and maintains a county-level arsenic occurrence map based on existing test data.
Key Facts
| EPA MCL | 10 µg/L (10 ppb) |
| MCLG | Zero |
| Primary source | Glacial outwash and alluvial aquifer sediments in southern Lower Peninsula under reducing conditions |
| Survey findings | Michigan EGLE private well survey found elevated arsenic across multiple Lower Peninsula counties |
| State program | Subsidized testing available; county-level arsenic occurrence maps provided by EGLE |
| State regulator | Michigan EGLE |
| Health effects | Bladder, lung, skin cancer; cardiovascular; diabetes risk |
| Effective treatment | Reverse osmosis or activated alumina — iron oxidation filters also effective in iron-rich MI well water |
Why Arsenic Matters in Michigan
Michigan has approximately 1.1 million households relying on private wells, and arsenic is among the most frequently detected contaminants in these wells. Michigan EGLE's private well survey data has documented elevated arsenic across a large portion of the southern Lower Peninsula — particularly in counties with glacial outwash and alluvial aquifer geology. The state's proactive approach — including subsidized testing, county arsenic maps, and public education — has helped identify and address exposure, but a large number of private well owners may still be unaware of their arsenic levels.
Michigan Arsenic Program
Michigan EGLE monitors arsenic under federal SDWIS and has documented elevated arsenic in the glacial aquifer system in several counties. Michigan's Upper Peninsula has elevated arsenic related to historic copper mining geology. EGLE maintains a private well database and recommends testing for all private well owners in areas with documented arsenic occurrence.
Michigan Utilities With Arsenic Violation Records
The utilities listed below have at least one arsenic violation on record in EPA's SDWIS database. Violations may be open or resolved — see individual utility pages for current status and risk level.
How Does Arsenic Get Into Drinking Water?
Arsenic in drinking water is almost always naturally occurring — it leaches from arsenic-bearing rocks and minerals into groundwater over time. New England granite, Southwest volcanic geology, and Upper Midwest glacial aquifers are the primary high-risk formations. It has no taste, odor, or color.
Full arsenic overview — geology maps, health effects, all 50 statesWho Should Pay Closest Attention
Private well owners across Michigan's southern Lower Peninsula face the highest risk, particularly in Allegan, Kent, Barry, Ionia, Montcalm, Newaygo, Muskegon, and Ottawa counties with glacial outwash aquifer geology. Upper Peninsula residents near copper and iron mining districts also face potential arsenic exposure from mining-influenced groundwater.
Private well owners near mining districts or agricultural areas
Residents in states with documented volcanic or geothermal geology
Long-term consumers of water from small groundwater systems
Households in homes built before 1960 with older well casings
Residents whose well water has never been tested for arsenic
Anyone living in a state where bedrock wells are common
How to Check Your Situation in Michigan
- 1
Identify your water source. If you use a public utility, use the ZIP lookup on this page to find your system and check its compliance record.
- 2
If on public water, review your utility's most recent Consumer Confidence Report (CCR) for arsenic monitoring data. The MCL is 10 ppb — your report should show recent test results.
- 3
If on a private well, order an arsenic test from a Michigan Department of Environment, Great Lakes, and Energy-certified laboratory. A basic arsenic test costs $15–$40. The state agency website maintains a certified lab list.
- 4
Test your well at the tap — not just at the wellhead. The entire water distribution system within your home can affect water quality.
- 5
If your test shows arsenic above 5 ppb, install certified treatment immediately. If above 10 ppb, do not use the water for drinking or cooking until treatment is installed.
- 6
Retest after installing treatment to confirm it is working as certified. Replace filter media on the manufacturer's schedule — an exhausted filter may not perform as rated.
Treatment Options for Arsenic
Boiling does not remove arsenic — it concentrates it. Standard activated carbon filters (Brita, etc.) do not effectively remove arsenic. Certified treatment is required.
NSF/ANSI Standard 58 — Reverse Osmosis
RO systems certified to NSF/ANSI 58 remove 85–95% of arsenic. Under-sink installation. Most effective for removing multiple contaminants simultaneously. Replace membranes and pre-filters on schedule.
Activated Alumina Filters
Activated alumina is specifically designed for arsenic and fluoride removal. Point-of-use or whole-house options available. Must be certified by NSF International or WQA for arsenic reduction. Requires periodic media regeneration or replacement.
Iron/Manganese Oxidation Filters
Effective for arsenic in iron-rich well water, which is common in the Midwest and New England. Oxidation converts dissolved iron and arsenic to a form that can be filtered out. Best when arsenic is co-occurring with high iron levels.
What does NOT work for arsenic
Standard activated carbon filters (Brita, refrigerator filters, most pitcher filters) do NOT effectively remove arsenic. Boiling concentrates arsenic. Water softeners do not remove arsenic. Only use products with NSF certification specifically for arsenic reduction.
Take Action Now
If you use a private well in Michigan, test for arsenic — especially if you are in a region with granite, volcanic, or sedimentary geology. A basic arsenic test costs $15–$40 at a state-certified lab.
Public water users: check your utility's Consumer Confidence Report (CCR) for arsenic results. The EPA MCL is 10 ppb — any detection warrants attention.
If arsenic is detected above 10 ppb (or even below it, given MCLG is zero), install an NSF/ANSI 58-certified reverse osmosis system for drinking and cooking water.
Standard carbon filters do NOT remove arsenic — do not rely on a Brita or refrigerator filter for arsenic protection.
Frequently Asked Questions
Related Pages
Arsenic — National Overview
All U.S. utilities with arsenic records
Michigan State Overview
All utilities and water quality data
Michigan Well Water Guide
Testing, risks & certified labs for private wells
Reverse Osmosis Guide
Removes 85–95% of arsenic
Best Arsenic Filter Guide
What actually works (carbon doesn't)
PFAS in Drinking Water
The 'forever chemical' contamination overview
All Contaminants
Complete reference library
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
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