About 201 households in Henderson County, 7% of the county, rely on a private well. Nobody tests that water unless the owner does.
Roughly 7% of Henderson County households, about 201, 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.
Private wells in Henderson 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.
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.
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.
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.
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.
No state-certified lab sits within 40 miles of the center of Henderson 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.
3 licensed contractors serve Henderson County, including Joseph W Allen, Corwin D Gingerich and Klint D Gingerich and Latta Well & Pump Corp. 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.
3 licensed contractors
License 092-008408, 092-008374, 092-008051, 092-009075, 092-008994, 092-008986, 101-005668 Active
License 092-009059, 092-009422, 102-002763, 102-004702 Active
License 101-808012 Active
Wells in Henderson County typically reach 90 to 180 feet; the median of 97 private water wells on the ISGS ILWATER map drilled since 2000 is 120 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.
90 to 180 feet; the median of 97 private water wells on the ISGS ILWATER map drilled since 2000 is 120 feet
Neighboring counties: Warren County, McDonough County, Mercer County, Hancock County.
National ranges from published 2025 to 2026 contractor pricing. Local quotes vary with depth, access and materials.
About 201, or 7% of households, based on Census housing data and state well surveys. The share is highest outside the towns with public water.
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.
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.
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.
