Well Water Testing in Franklin Township, NJ
Franklin Township was settled around 1700 by Quakers who arrived from Burlington County, making it one of Hunterdon County's older communities. About 3,270 people live across just over 23 square miles, and the township is close to entirely on private wells: NJDEP's records show 589 tests since 2002 and almost none of the land inside a mapped public water service area. Its test results have one feature that sets it apart from most of Hunterdon. It is not arsenic, radiological or acidic water that stands out here. It is bacteria.
What well tests in Franklin Township have found
NJDEP's Private Well Testing Act summary (September 2002 to December 2024) covers 589 untreated wells in the township.
- Total coliform: present in 35.1% of wells, against 23.1% across Hunterdon County.
- E. coli: present in 8.5%, about two and a half times the county's 3.3% and the highest rate of any Hunterdon municipality with a published figure.
- Arsenic: 7.7% exceeded the limit (county: 15.7%).
- pH: 31.7% outside the optimum range (county: 28.1%).
- Iron and manganese: 12.7% and 11.5%.
- Radiological: gross alpha in 5.1% of 549 wells; uranium in 0% of 165.
- PFAS: 2.4% of 85 wells tested since late 2021.
What the bacteria numbers mean
Total coliform is a broad indicator of a pathway from the surface into the well. E. coli is more specific and more serious, because it points to fecal contamination from people or animals. Neither is a property of the rock. Bacteria depend on how the well is built and maintained, how close it is to a septic system or livestock, and how well it is sealed. A positive result is usually a fixable problem: shock disinfection and a follow-up test resolve many cases, and a persistent problem may call for a UV or other treatment system. It also makes Franklin a place where the retest is not an afterthought.
The rock beneath Franklin
The NJ Geological Survey's generalized map puts essentially all of Franklin, about 100%, on Triassic siltstone, shale, sandstone and conglomerate, the Newark Basin's sedimentary rock. Arsenic is present here, at 7.7% of wells, but well below the roughly 22% average across the county's Newark Basin towns, and the gap between Franklin and East Amwell Township, where 42.5% of wells exceeded the arsenic limit, is a reminder that rock type sets a range, not the exact result.
Public water or a private well?
NJDEP's 2017 purveyor map shows about 1.2% of the township inside a mapped service area, so private wells serve nearly all households. Neighboring Clinton is different: most of the town is on a public system.
Buying or selling in Franklin Township
For a well-served home here, bacteria is the most likely surprise.
- Ask about the well's history. Casing and cap condition, the last disinfection, and the distance to the septic system all matter.
- Plan for a possible retest. If coliform or E. coli is detected, expect disinfection and a confirmation sample. That takes days, so build it into the timeline.
- Do not overlook the rest of the panel. Arsenic is flagged in one well out of thirteen, and low pH in about one out of three.
Both parties must receive and review the results before closing, and the contract decides who pays. The PWTA page covers the panel, and the treatment referral page covers what happens after a failed result.
Renting out a property in Franklin Township
Rental properties on a well need a retest at least every five years, with a copy to each tenant within 30 days. Because bacteria results depend on a well's condition, a landlord with older equipment should treat the retest as a chance to catch problems early. Tests before December 2021 have no PFAS result. See landlord testing.
How this compares with neighboring towns
Percent of tested wells above the limit for arsenic and gross alpha, or outside the optimum pH range, with the number of wells behind each figure:
- Raritan Township: arsenic 22.2%, pH 7.2%, gross alpha 11.2% (2,269 wells)
- Clinton Township: arsenic 3.6%, pH 40.3%, gross alpha 7.7% (928 wells)
- Alexandria Township: arsenic 23.5%, pH 34.4%, gross alpha 1.5% (863 wells)
- Union Township: arsenic 6.5%, pH 43.9%, gross alpha 0.5% (616 wells)
Questions from Franklin homeowners
My well passed once. Could it fail now?
Yes, for bacteria in particular. A well can be clean one year and contaminated the next after a heavy rain, a failing seal, or a septic issue. That is why routine retesting matters even beyond the legal schedule.
Is E. coli in a well an emergency?
It is a reason to stop drinking the water untreated and to act quickly. Boiling or using bottled water until the well is disinfected and retested is standard advice.
If I am not selling, how often should I test?
The New Jersey Department of Health encourages well owners to test every year for total coliform, nitrate and pH. In a township where bacteria are found more often than almost anywhere else in the county, an annual coliform test is the most practical habit an owner can adopt. It is inexpensive relative to what it can catch, and the results can be compared year to year.
Does the uranium requirement matter here?
It applies. Locally, none of 165 tested wells exceeded the uranium limit. See why Hunterdon requires it.
Also nearby: Alexandria Township, Clinton Township, Raritan Township and Union Township.