Guide 7 of 12
Private well testing before you buy a lake home
References checked Oct 4, 2026.
Short answer: In Pennsylvania, private wells are not regulated like public water systems, so testing is up to the owner.12 Before you buy, have a certified lab test the water. Penn State Extension recommends testing every year for coliform bacteria and E. coli, and every three years for pH, total dissolved solids and contaminants linked to nearby land uses.3
How many people rely on private water
Penn State Extension says there are over one million private wells in Pennsylvania, and over three million people get their water from a private well, spring or cistern.4
Who regulates a private well?
DEP answers its own question, "Does the state of Pennsylvania regulate private homeowner wells?" with "No."2 Penn State Extension says private water supplies are not regulated and that all testing, maintenance and treatment are the property owner's responsibility.1 It also reports that research has found more than half of these private water systems fail at least one drinking water standard.1
Some townships do have their own well ordinances. On Oct 4, 2026, for example, Blooming Grove and Dingman townships in Pike County listed well ordinances among their posted ordinances.5 Ask the township where the home is.
What a home inspection doesn't cover
Pennsylvania's home inspection law says an examination limited to wells, or to air and water quality, is not a "home inspection."6 Plan a separate water test.
What to test, and how often
Penn State Extension's testing guide recommends:3
- Every year: total coliform bacteria and E. coli. E. coli points to human or animal waste reaching the water.
- Every three years: pH and total dissolved solids (TDS), which act like a general check-up of water quality.
- Every three years: extra tests tied to land uses you can see from the home. Penn State's guide pairs common land uses with the pollutants to test for.
- Lead and copper from plumbing: collect a "first-draw" sample after water has sat in the pipes for at least 12 hours.
Penn State also suggests a thorough yearly check by the owner and a professional inspection of the water system at least every ten years.4
Use a certified lab
Penn State Extension says all water tests should be done by a certified water testing laboratory, and to be cautious of results from uncertified labs or water treatment salespeople.3 DEP keeps a list of accredited drinking water labs.3 Most samples can be collected by the homeowner with the lab's containers and instructions; a few tests, such as radon in water, usually need lab staff.3
Reading the results
Penn State's guide gives two quick benchmarks. Water with a pH below 6.5 or above 8.5 can corrode lead and copper from household plumbing or taste bad.3 Total dissolved solids should be below 500 milligrams per liter and shouldn't change much from one test to the next; an increase can mean pollution has occurred and more detailed testing is needed.3 If coliform bacteria are found, the lab can follow up with an E. coli test. A positive E. coli result is more serious, because it shows human or animal waste is reaching the water.3
Springs and cisterns
Some rural homes use a spring instead of a drilled well. Penn State Extension says springs are very susceptible to bacterial contamination, should be disinfected after construction and then tested, and should be tested at least every year.4
A simple order of operations
- Ask the seller for every past water test and any treatment equipment records.
- Book a certified lab early; some special tests need lab staff to collect the sample.3
- Ask the lab for the Penn State basics (coliform and E. coli, pH, TDS) plus tests for nearby land uses.3
- If anything fails, ask what treatment would fix it, and get a quote before your inspection period ends.
Lake-home specifics
- Septic and wells share the same lot. Ask how far the well is from the septic absorption area on this lot and on neighbors' lots.
- Seasonal homes. Ask the lab how to sample a house that has been closed for the season.
- Shared or community water. If the home is on a shared or community water system rather than its own well, ask who operates it and for its recent test results.
What the seller must disclose
The disclosure form must cover water and sewage systems or service.7 Sellers disclose known material defects and need not investigate.7 Ask for past test results in writing.
FAQ
- Does the state test private wells?
- No. DEP says it does not regulate private wells.2 Testing is up to the owner.1
- What is the minimum test before buying?
- Penn State's yearly test is total coliform bacteria and E. coli; its three-year tests add pH, TDS and land-use-related contaminants.3 Ask your lab what fits the property.
- Can I take the sample myself?
- Usually yes, using the lab's sterile containers and instructions; some special tests need lab staff.3
- Does a home inspection include water testing?
- Not under Pennsylvania's definition of a home inspection, which excludes exams limited to wells or water quality.6
- Can a lab test the water for radon?
- Penn State Extension lists radon among the special tests that usually need a lab employee to visit and collect the sample.3 Ask the lab when you book.
- Where do I find a certified lab?
- Penn State Extension points to DEP's current listing of accredited drinking water testing laboratories.3 DEP's private wells page also links information on water testing, certified labs and treatment devices.2
Lakes where this comes up
- Arrowhead LakeMonroe County
- Gold Key LakePike County
- Big Bass LakeLackawanna County
- Canadohta LakeCrawford County
- Deer LakeFayette County
- Indian Mountain LakeMonroe County
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