State Well Water Guide
Kansas Private Well Water Guide
Approximately 28% of Kansas residents — nearly 800,000 people — rely on private wells. Kansas sits atop the High Plains (Ogallala) Aquifer — one of the world's largest — but intensive agriculture has significantly degraded water quality in shallow layers. Nitrate contamination is the dominant concern, with some of the highest agricultural nitrate concentrations in the U.S. documented in central and western Kansas. Atrazine (a widely used herbicide) contamination in shallow wells is also a significant issue. Naturally occurring arsenic is present in some aquifer layers. The Kansas Department of Health and Environment (KDHE) provides well construction oversight but not ongoing monitoring requirements.
Testing Guidance
KDHE and K-State Research and Extension recommend annual bacteria and nitrate testing for all private wells. Atrazine testing is strongly recommended for wells in row-crop farming areas — Kansas is one of the nation's top atrazine-using states. Arsenic testing is warranted for wells in the Permian redbeds geology of south-central Kansas (Barton, Stafford, Pratt, and Reno counties). Uranium has been documented in some High Plains wells in northwest Kansas. Fluoride is naturally elevated in some formations in central Kansas.
What to Test For in Kansas
Total coliform bacteria and E. coli — annual minimum for all wells
Nitrates — annual for all agricultural area wells; the single most important test in Kansas
Atrazine and other herbicides — row-crop farming areas statewide
Arsenic — south-central Kansas Permian redbed geology
Uranium — northwest Kansas High Plains wells
Fluoride — central Kansas formations
Iron and manganese — eastern Kansas wells
Total dissolved solids (TDS) — western Kansas; groundwater becomes increasingly mineralized moving west
Common Contamination Risks in Kansas
Nitrate contamination — some of the highest agricultural nitrate concentrations in the nation; multiple Kansas counties have well exceedance rates above 20%
Atrazine — Kansas is among the highest atrazine-use states; the herbicide has been detected in wells across the corn and sorghum belt
Naturally occurring arsenic in Permian redbed geology in south-central Kansas
Uranium in High Plains Aquifer layers in northwest Kansas
Declining water table — the Ogallala Aquifer is dropping 1–3 feet per year in western Kansas, concentrating minerals and increasing contamination risks
Contaminant Guides Relevant to KS Wells
PFAS
Synthetic Chemicals
EPA limit: 4 ppt
Lead
Heavy Metals
EPA limit: 15 ppb (action level)
Nitrates
Agricultural Chemicals
EPA limit: 10 mg/L
DBPs
Disinfection Byproducts
EPA limit: 80 µg/L (TTHMs) / 60 µg/L (HAA5)
Arsenic
Heavy Metals
EPA limit: 10 ppb
Hard Water
Minerals
EPA limit: No federal limit
Chlorine
Disinfection Chemicals
EPA limit: 4 mg/L (MRDL)
Microplastics
Emerging Contaminants
EPA limit: No federal limit
Bacteria
Microbial Contamination
EPA limit: Zero E. coli / < 1 coliform per 100 mL
Fluoride
Minerals
EPA limit: 4 mg/L (MCL) / 2 mg/L (Secondary MCL)
Chromium-6
Heavy Metals
EPA limit: 100 ppb (total chromium)
Copper
Heavy Metals
EPA limit: 1.3 mg/L (action level)
Radon
Radioactive Contaminants
EPA limit: No finalized MCL
Iron & Manganese
Minerals
EPA limit: 0.3 mg/L iron / 0.05 mg/L manganese (aesthetic SMCLs)
Atrazine
Agricultural Chemicals
EPA limit: 3 ppb (0.003 mg/L)
Uranium
Radioactive Contaminants
EPA limit: 30 µg/L (30 ppb)
Perchlorate
Industrial Chemicals
EPA limit: 0.056 mg/L (56 ppb)
VOCs
Industrial Chemicals
EPA limit: Varies by compound: benzene 5 ppb; TCE 5 ppb; PCE 5 ppb; vinyl chloride 2 ppb
Radium
Radioactive Contaminants
EPA limit: 5 pCi/L (combined Ra-226 + Ra-228)
Crypto & Giardia
Microbial Contamination
EPA limit: Zero (treatment technique standard)
Hydrogen Sulfide
Naturally Occurring Compounds
EPA limit: No MCL; Secondary MCL (aesthetic) of 0.05 mg/L
Selenium
Minerals
EPA limit: 50 ppb (0.05 mg/L)
Cadmium
Heavy Metals
EPA limit: 5 ppb (0.005 mg/L)
Mercury
Heavy Metals
EPA limit: 2 ppb (0.002 mg/L)
Barium
Heavy Metals
EPA limit: 2 mg/L
pH
Water Quality Indicators
EPA limit: 6.5–8.5 (secondary standard)
Find a Certified Lab in Kansas
Use the Kansas state-certified laboratory program to find accredited labs for private well testing. Always verify current certification before submitting samples.
KS Certified Lab Directory ↗Kansas Well Water FAQs
Related Pages
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
Quick Reference
State program
KS Certified Labs ↗EPA guidance
EPA Private Wells Program ↗State lab directory
KS Certified Labs ↗Minimum Annual Tests
Plus state-specific contaminants listed above
Other State Guides