Illinois county well guide

Well Water in Greene County, IL: Testing, Contractors and Rules

About 744 households in Greene County, 14% of the county, rely on a private well. Nobody tests that water unless the owner does.

Labs within 40 milesLicensed contractors
14%of households on a private well
Share on wells, county vs state
Greene County14%
Illinois average9%
5licensed contractors serve the county
40+ mito a certified lab; mail-in kits recommended
Nostatewide test required when a home is sold

Roughly 14% of Greene County households, about 744, get their water from a private well rather than a utility. They are concentrated in the rural parts of the county, and they are on their own for testing.

Local rules for wells in Greene County

Private wells in Greene County follow Illinois's statewide rules, administered by Illinois Department of Public Health, Private Water Program. A water test is required when a new well is completed. There is no statewide test requirement when a home is sold, though lenders often ask for one. The cards below show the details and the official sources.

At a glance

Water test for a new wellRequired

A permit from the county health department (or IDPH where the county has no delegated program) is required before a private well is drilled, the well must be built by an IDPH licensed water well contractor to the Illinois Water Well Construction Code (steel or approved plastic casing, grout, the setbacks from septic systems and other sources, a sanitary well cap above grade), and the contractor files a well construction report with IDPH. Under the code the new well is disinfected and a bacteria sample is collected, in most counties by the health department at the final inspection, before the well is approved for use; the health department's sign-off is what the building department wants before occupancy.

Water test when a home is soldNot required statewide

No statewide requirement. The Illinois Residential Real Property Disclosure Report asks the seller about the water supply and any known defects, and FHA, VA and USDA loans require a bacteria, nitrate and lead sample from a certified lab before closing. A few counties run point-of-sale well and septic inspection programs under local ordinance, so ask the county health department.

What the state recommends

IDPH recommends testing a private well every year for coliform bacteria and nitrate, after any repair or flooding, and whenever the taste, color or smell changes; a chemistry panel (arsenic, iron, manganese, hardness, chloride, sulfate) when the well is new or every few years; and, depending on the aquifer, radium and barium for deep sandstone wells in northern Illinois, arsenic for wells in the Mahomet and other glacial aquifers of central Illinois, and pesticides and nitrate for shallow wells in farm country. County health department labs run the bacteria test cheaply, and the IDPH state lab tests samples submitted through the county.

Free or low-cost testingAvailable

No statewide free program. Most county health departments sell a bacteria (and often nitrate) sample kit for a small fee and explain the result, and the IDPH Division of Laboratories runs the bacteria test for counties without their own lab. The Illinois State Water Survey and university extension programs run periodic free nitrate and arsenic screening clinics in farm counties.

Getting your water tested near Greene County

No state-certified lab sits within 40 miles of the center of Greene County. That is common in rural Illinois, and the practical answer is a mail-in kit: the lab ships bottles, you sample at the kitchen tap and ship them back cold. The finder below widens the search to the whole state.

No listings yet for this area. Try widening your search.

Licensed well contractors serving Greene County

5 licensed contractors serve Greene County, including Edward K Greenfield and James Ray Erwin. Each profile carries the state license number and the date we checked it, and the filters below sort them by drilling, pump work or treatment.

Well depth and water chemistry

Wells in Greene County typically reach 40 to 50 feet; the median of 105 private water wells on the ISGS ILWATER map drilled since 2000 is 40 feet. What comes up with the water depends on the aquifer, and across Illinois the usual suspects are arsenic (naturally occurring in the glacial sand and gravel aquifers of central and northeastern illinois, including the mahomet aquifer, where roughly one well in ten is over the standard), iron and manganese (nearly universal in glacial aquifers). A first full panel tells you which of them apply to your well.

Typical well depth

40 to 50 feet; the median of 105 private water wells on the ISGS ILWATER map drilled since 2000 is 40 feet

Contaminants to test for
  • Arsenic (naturally occurring in the glacial sand and gravel aquifers of central and northeastern Illinois
  • Including the Mahomet aquifer
  • Where roughly one well in ten is over the standard)
  • Iron and manganese (nearly universal in glacial aquifers)
  • Hardness (very hard water statewide)
  • Radium and barium (the deep Cambrian-Ordovician sandstone aquifer of northern Illinois)
  • Coliform bacteria (old large-diameter bored and dug wells
  • Common in southern Illinois)
  • Nitrate and atrazine (shallow wells in corn and soybean country)
  • Chloride and sodium (road salt in the Chicago collar counties
  • And natural brine in deep wells)
  • Hydrogen sulfide and methane (deep wells in the south and the coal counties)
  • Fluoride (locally high in deep aquifers)

Neighboring counties: Scott County, Jersey County, Calhoun County, Morgan County.

What well work costs in Greene County

Basic bacteria and nitrate test$25 to $75lab fee, homeowner sample
Full panel lab test$150 to $400metals, VOCs, radiologicals
Well inspection$250 to $550flow, pressure, visual, water test
Submersible pump replacement$1,200 to $4,500parts and labor
Pressure tank replacement$400 to $1,200installed
Whole-house treatment system$800 to $6,000softener, iron filter, UV, RO
New well drilled$5,500 to $25,000about $25 to $65 per foot
Shock chlorination$80 to $300or about $20 as a DIY job

National ranges from published 2025 to 2026 contractor pricing. Local quotes vary with depth, access and materials.

Questions Greene County well owners ask

How many homes in Greene County are on a well?

About 744, or 14% of households, based on Census housing data and state well surveys. The share is highest outside the towns with public water.

Where is the closest certified lab to Greene County?

There is no certified lab within 40 miles. Use a mail-in kit from a Illinois certified lab, or the county health department if it collects samples.

Do I need a permit to drill a well in Greene County?

A permit from the county health department (or IDPH where the county has no delegated program) is required before a private well is drilled, the well must be built by an IDPH licensed water well contractor to the Illinois Water Well Construction Code (steel or approved plastic casing, grout, the setbacks from septic systems and other sources, a sanitary well cap above grade), and the contractor files a well construction report with IDPH. Under the code the new well is disinfected and a bacteria sample is collected, in most counties by the health department at the final inspection, before the well is approved for use; the health department's sign-off is what the building department wants before occupancy.

What does a well test cost near Greene County?

A bacteria and nitrate test runs $25 to $75 at most certified labs; a full panel with metals is $150 to $400. Mail-in kits cost about the same as walking in.