New York county well guide

Well Water in St. Lawrence County, NY: Testing, Contractors and Rules

About 16,753 households in St. Lawrence County, 38% of the county, rely on a private well. Nobody tests that water unless the owner does.

Labs within 40 milesLicensed contractors
38%of households on a private well
Share on wells, county vs state
St. Lawrence County38%
New York average25%
6licensed contractors serve the county
40+ mito a certified lab; mail-in kits recommended
Nostatewide test required when a home is sold

St. Lawrence County has an estimated 16,753 households on private wells, 38% of the county. If you are one of them, testing, treatment and repairs are yours to arrange.

Local rules for wells in St. Lawrence County

Private wells in St. Lawrence County follow New York's statewide rules, administered by NYS Department of Environmental Conservation. No water test is required by the state 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 wellNot required statewide

No single statewide rule. The driller must be DEC-registered, file a preliminary notice before drilling, disinfect the finished well under NYSDOH Appendix 5-B, and send a well completion report to DEC and to you within 30 days. NYSDOH says a new well should be tested before use for coliform bacteria, nitrate, nitrite, arsenic, lead, iron, manganese, sodium, hardness, pH and turbidity. Many county health departments (Westchester, Rockland, Putnam, Dutchess, Suffolk and others) require a permit and a passing water test before a new well can be used.

Water test when a home is soldNot required statewide

No statewide requirement. A few counties and towns require a well test or well inspection when a property changes hands, and FHA, VA and USDA loans usually ask for a bacteria and nitrate test. Check with the county health department.

What the state recommends

NYSDOH recommends a coliform bacteria test every year, plus a first-time panel of nitrate, nitrite, arsenic, lead, iron, manganese, sodium, sulfate, hardness, pH, alkalinity and turbidity, then periodic re-testing of whatever showed up. Add radon, uranium, methane or PFAS where they are known in your area.

Free or low-cost testingAvailable

No statewide free program. Several county health departments run their own ELAP-certified labs and sell low-cost bacteria and nitrate tests (Erie, Monroe, Suffolk, Nassau, Cattaraugus, Chautauqua, Allegany). Others keep a list of local certified labs.

Getting your water tested near St. Lawrence County

No state-certified lab sits within 40 miles of the center of St. Lawrence County. That is common in rural New York, 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 St. Lawrence County

6 licensed contractors serve St. Lawrence County, including Atlantic Testing Laboratories, Limited and Cleve Greenhill Well Drilling. 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 St. Lawrence County typically reach 100 to 400 ft in bedrock across most of upstate; 30 to 150 ft in glacial sand and gravel valleys and on Long Island. What comes up with the water depends on the aquifer, and across New York the usual suspects are coliform bacteria, nitrate (farm valleys and older septic areas), arsenic (parts of central and western new york), iron and manganese. A first full panel tells you which of them apply to your well.

Typical well depth

Varies by location. Check the state well record search for logs of nearby wells.

Contaminants to test for
  • Coliform bacteria
  • Nitrate (farm valleys and older septic areas)
  • Arsenic (parts of central and western New York)
  • Iron and manganese
  • Hardness (limestone country)
  • Sodium and chloride (road salt)
  • Sulfate and hydrogen sulfide (shale areas)
  • Radon and uranium (Southern Tier and Adirondack bedrock)
  • Methane (Southern Tier shale)
  • PFAS (Hoosick Falls
  • Newburgh and other hot spots)
  • Barium and fluoride (western New York)

Neighboring counties: Franklin County, Jefferson County, Lewis County, Hamilton County.

What well work costs in St. Lawrence 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 St. Lawrence County well owners ask

How many homes in St. Lawrence County are on a well?

About 16,753, or 38% 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 St. Lawrence County?

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

Do I need a permit to drill a well in St. Lawrence County?

No single statewide rule. The driller must be DEC-registered, file a preliminary notice before drilling, disinfect the finished well under NYSDOH Appendix 5-B, and send a well completion report to DEC and to you within 30 days. NYSDOH says a new well should be tested before use for coliform bacteria, nitrate, nitrite, arsenic, lead, iron, manganese, sodium, hardness, pH and turbidity. Many county health departments (Westchester, Rockland, Putnam, Dutchess, Suffolk and others) require a permit and a passing water test before a new well can be used.

What does a well test cost near St. Lawrence 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.