Well water in Mackinac County, Michigan
No public well test results have been compiled for Mackinac County yet. The USGS national arsenic model estimates that 7% of the 7,421 people on private wells there draw water with arsenic above 10 ug/L, the EPA limit, based on geology, well depth and land use rather than local tests.
The strongest signal is coliform bacteria: Recommended for every private well, every year, too few samples to carry the headline but first on the test list below.
95 test results across 10 contaminants from at least 7 wells, 1976 to 1988; nitrate has the most at 18. Data refreshed September 15, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 7,421 people in Mackinac County get their drinking water from a private well, per USGS 2015 county water use. That is about 68% of residents.
Separately, the USGS national arsenic model estimates that 7% of the 7,421 people on private wells in Mackinac County draw water above 10 ug/L (the model's range is 5% to 9%), from geology and well depth rather than local tests.
What individual samples found
Each row summarizes every public sample for that contaminant inside Mackinac County. Above limit means above the EPA maximum contaminant level; where EPA has no enforceable limit, the row shows a health guideline or nuisance level instead.
| Contaminant | Above limit | Samples | Detected | Median | Highest | Limit |
|---|---|---|---|---|---|---|
| Nitrate 1976 to 1988 | 18 | 28% | 0 | 0.51 | 10 mg/L EPA limit |
Sampled fewer than 10 times, too few to summarize: Lead (8), Fluoride (9), Copper (9), Arsenic (9), Uranium (6), Manganese (9), Iron (9), Chloride (9), Sodium (9).
Closer than the county
See the sampled wells near your address
The same records, drawn around one point: which wells within a few miles were sampled and what they found, how deep the wells next to you were drilled, and any leaking tank or cleanup site within a mile.
Check my addressWhat this means
Among contaminants with a federal limit, no tested sample in Mackinac County came back above it. That is reassuring, but sampling is uneven: wells that were never tested are not in this data.
Manganese, Iron, and Chloride are widespread in local groundwater. They are mainly a staining and taste problem, but high manganese also carries a health advisory for infants.
What to test for in Mackinac County
- 1Coliform bacteriaRecommended for every private well, every year.
- 2NitrateRecommended for every private well, especially near farms or septic systems.
- 3LeadAbove the limit in 1 of 8 local samples; too few to quote a rate.
- 4FluorideDetected in 100% of local samples.
- 5CopperDetected in 100% of local samples.
- 6IronDetected in 100% of local samples.
- 7ChlorideDetected in 100% of local samples.
- 8Volatile organic compounds (VOCs)30 leaking underground storage tank sites on record locally.
- 9Metals panel56 hazardous waste sites on record locally.
Test your Mackinac County well for coliform bacteria, nitrate and lead
Certified lab analysis of your own tap water, bottles and prepaid return shipping included. The Essential well panel covers arsenic, uranium, nitrate, lead, copper, manganese, iron, sodium and bacteria; radon and PFAS are add-ons.
Order the Tap Score well water test kit, from $209Already tested? Upload the report
Just want bacteria checked first? Tap Score coliform and E. coli test, $99. Coliform and E. coli are the tests every well needs every year.
Want a quick look before paying for a lab? Home well water test strips on Amazon check hardness, iron, pH and nitrate in minutes. They are a screen, not a result: arsenic, bacteria, uranium and PFAS need a certified lab.
Affiliate links: the merchant pays us a commission and the price is the same for you. It does not change what the data above says. As an Amazon Associate we earn from qualifying purchases.
Where to get a well tested in Michigan: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Mackinac County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
Wells in Mackinac County
5,052 domestic wells in Mackinac County are on record with the state since 1955. 77% are drilled into bedrock, and the typical well is 99 feet deep (one in ten goes past 220 feet).
In a typical Mackinac County well, bedrock starts about 39 feet down, the median yield is 10 gallons per minute, 1% of wells yield under 3 gallons per minute and usually need a storage tank.
Bedrock wells are where arsenic, uranium and radon come from: the water sits in fractures in granite and metamorphic rock and picks up whatever the rock carries. That is why testing for those three matters more here than in a dug or gravel well.
Find your own well's report
The state keeps the driller's report for most wells drilled since 1984. It tells you how deep your well is, where bedrock starts, and how much water it makes, which decides what treatment can work.
- Open Wellogic (EGLE) and choose Water Well.
- The record lists depth, casing, static water level, the pump test and the geologic log.
Michigan has required well records since 1966, so most drilled wells are on file.
Official help in Michigan
Two places to start that are not selling anything: the state program that answers private well questions, and its list of labs certified to run drinking water tests. A certified lab is the difference between a result you can act on and a number.
- Private Residential Water Well Testing, Michigan EGLE
- Laboratory certification program, Michigan EGLE
Contamination sources on record in Mackinac County
Michigan EGLE records 30 leaking underground storage tank sites and 56 hazardous waste sites in Mackinac County, among 178 regulated sites in total. Groundwater does not follow property lines, so a well within a few hundred feet of one of these is worth testing for what that site could release.
- 30
- leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
- 56
- hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
- 92
- registered underground storage tank sitesRegistered tanks are regulated and inspected; they matter most when they are old or near a shallow well.
Treatment that fits the local profile
Iron
Oxidizing filter whole-house; Water softener (low levels); Aeration plus filtration
Manganese
Oxidizing filter (greensand, birm) whole-house; Water softener (low levels); Point-of-use reverse osmosis
Systems we would look at first
Some links below are affiliate links. If you buy through one, the merchant pays us a commission at no extra cost to you. It does not change which products we list or what the data says.
For manganese
Iron and manganese oxidizing filter
whole-house, at the point of entry, about $1,800
Air-injection or greensand media; fixes staining at the source.
Free, no obligation
Get on the list for a free in-home water test in Mackinac County
No water treatment company serves Mackinac County through Well Water Nerd yet. We are signing licensed companies on county by county: they test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Leave your details and you are first in line. Nothing is shared until a company joins for Mackinac County, and you get an email naming it first.
Common questions
How deep are wells in Mackinac County?
The typical domestic well in Mackinac County is 99 feet deep, based on 5,052 wells reported to the state since 1955. One in ten is deeper than 220 feet. 77% are drilled into bedrock.
How often should I test a private well in Mackinac County?
Test for bacteria and nitrate every year. Test once for arsenic, uranium, radon, fluoride, manganese and PFAS, then again every three to five years or after any change in taste, color, or plumbing.
Towns in Mackinac County
13 towns have fewer than 30 public samples and are included in the Mackinac County totals above rather than shown separately: Bois Blanc township, Brevort township, Clark township, Garfield township, Hendricks township, Hudson township, Mackinac Island, Marquette township, Moran township, Newton township, Portage township, St. Ignace, St. Ignace township.
Counties near Mackinac County
Closest first. Groundwater does not stop at a line on a map, so the next county over is a fair second opinion.
Want the numbers themselves? Download the Michigan dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 95 samples in Mackinac County. Data from the Water Quality Portal, a service of USGS, EPA and USDA; groundwater samples collected by USGS and cooperators. Retrieved September 3, 2026.
- USGS national arsenic model (Ayotte 2017): estimated share of 7,421 people on private wells in Mackinac County above 10 ug/L of arsenic, from geology, well depth and land use. County estimates of domestic well users with arsenic above 10 ug/L from the USGS national logistic regression model (Ayotte, Medalie and Qi, 2017), with private well population from the USGS 2015 county water-use compilation (Dieter and others, 2018). Retrieved September 15, 2026.
- Michigan Wellogic well records: 5,052 well records in Mackinac County, 5,052 domestic. Water well records from Wellogic, the Michigan Department of Environment, Great Lakes, and Energy statewide well database. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 16, 2026.
- Michigan EGLE regulated sites: 178 regulated sites located in Mackinac County. Part 201 environmental contamination sites, underground storage tank facilities and Part 115 landfills from the Michigan Department of Environment, Great Lakes, and Energy. Retrieved September 16, 2026.
Non-detects count as samples and are treated as zero when computing medians. Exactly at the limit counts as not above it. A sample belongs to the town containing the well's reported coordinates.