What FHA asks for
HUD Handbook 4000.1, last revised August 12, 2026, sets the federal floor. Yield first: a well serving new construction has to deliver 5 gallons per minute continuously over at least a four-hour period, and an existing well a minimum of 3 gallons per minute continuous.
Distances, for existing construction: 10 feet to the property line, 50 feet to a septic tank, 100 feet to the drain field, with the drain field reducible to 75 feet where the local authority allows it. Where local requirements are stricter, the local requirement prevails.
Water quality has to meet the standard of the health authority with jurisdiction; where no local or state standard exists, the EPA’s National Primary Drinking Water regulations apply. A test is required on newly constructed properties, where the appraiser reports a deficiency, where water is known or reported to be unsafe, and where the property sits close to a dump, landfill, industrial site or farm.
Some water sources end the conversation. A property served by a spring, lake, river, sand-point well or artesian well, or carrying a mechanical chlorinator, is not eligible for FHA mortgage insurance.
The county rule is stricter, so the county rule controls
Chester County Health Department Rules and Regulations Chapter 500, section 501 governs wells here, and it out-measures the federal standard at the two distances that come up most.
| From the proposed well | Minimum |
|---|---|
| Sewage absorption areas, cesspools, seepage pits, spray irrigation | 100 feet |
| Septic, aerobic, sewage pump and holding tanks | 50 feet |
| Farm silos, barnyards, manure pits or storage | 100 feet |
| Bio-solids and septage disposal areas | 300 feet |
| Fuel or petroleum tanks over 1,000 gallons | 300 feet |
| Home heating oil tanks of 1,000 gallons or less | 30 feet |
| Wetlands, floodplains, ponds, streams, detention basins | 25 feet |
A county permit is required to construct any well and to install pumping equipment, and drillers, pump installers and geothermal contractors have to hold a county license. Water must be drawn from a formation at least 25 feet below the ground surface. So the well on a Chester County farmette carries a permit number, and that permit file is worth pulling.
The water test, and who is allowed to draw it
Section 501.13.2 sets the pass-fail panel: total coliform under 1 cfu per 100 ml, nitrate 10 mg/L as nitrogen, arsenic 0.01 mg/L, iron 0.3, manganese 0.05, chloride 250, total dissolved solids 500, turbidity 5 NTU, pH between 5.5 and 8.5. Residual chlorine has to read zero, because its presence invalidates the coliform result, and every microbiological sample gets checked for it.
Section 501.13.1 settles who takes the sample: an employee of a Pennsylvania DEP-certified laboratory, or a county-licensed well driller or pump installer. Not the owner. The report has to name the permittee, the sample address and township, the county well permit number, who drew it, and whether the water was treated. Results go to the Health Department within 30 days.
FHA’s disinterested-third-party rule and the county’s licensing rule land in the same place, which makes this the one part of a rural file where the two rulebooks agree without argument.
Septic, Act 537 and a lot you want to build on
Section 503 is the septic half. The Health Department administers the Pennsylvania Sewage Facilities Act — Act 537 — and adopts 25 Pa. Code Chapters 71, 72 and 73 by reference. It issues on-lot sewage permits, runs the site testing (soil probe, dual-depth percolation tests, limiting-zone identification), enforces a replacement-area policy so a reserve absorption area stays preserved on the lot, and publishes an evaluation procedure for existing systems plus a route to verify prior testing.
For a lot you intend to build on, the sequence starts earlier than most buyers expect. Every municipality keeps an official sewage facilities plan, and a new lot served by on-lot sewage needs a planning module or a documented exemption before the county permit can issue. Perc results decide the size and placement of the system, which decides where the house can sit, which decides what the builder can price. Do it in that order.
Historic well and sewage permit designs can be pulled from the county’s electronic permit search. On an older property that is often the fastest way to find out what is actually in the ground.
The township rules on top
Municipalities add their own on-lot management requirements, and they are not uniform.
- Kennett Township requires on-lot owners to file proof of pumping every three years, and charges a sewer connection fee of $7,316 per equivalent dwelling unit where a public district reaches the property.
- Pennsbury Township requires septic systems to be pumped and inspected every three years, with notice to the township.
- London Grove Township has run an on-lot sewage management ordinance since March 2012, with pumping at least every three years.
Ask the township directly for its rule and for the file on the property. Whether the last pump-out happened on schedule is the kind of thing that turns up two days before closing.
The sequence, and who pays
- Put the well and septic tests in the agreement of sale by name, with a deadline and a stated party paying for each. Silence here is what causes the argument later.
- Order the water sample through a certified laboratory or a county-licensed installer. Never draw it yourself.
- Order the septic evaluation, and pull the county permit file for the original design and the replacement area.
- Get the yield test run on the well against the 5 or 3 gallon-per-minute standard that applies.
- Let the appraiser report condition, and expect the lender to ask for the reports before clearing conditions.
- Put any correction, retest or repair in writing before closing, with who does it and when.
Allow calendar for it. The lab needs the sample, the county wants the report within 30 days of it, and a pumper is not always available on the day the schedule needs one. Township, acreage, and whether the house runs on a well or on-lot septic: say those three and a licensed Pennsylvania lender calls you back, usually the same business day, to sort out which inspections the file will need.