Buying a house with septic and a well

A house on septic and a well can be a great place to live. It also comes with two systems that are expensive to replace and that a standard home inspection may barely touch. A little homework during the contract period can save you from inheriting a failing drainfield or a contaminated well.

Records to ask the seller for

• Septic permit and site drawing, often held by the county or city health department. They show the system type, tank size, and where the tank and drainfield are.
• Pumping and inspection receipts. Regular service, which EPA says is inspection at least every three years and pumping typically every three to five years, is a good sign. No records at all is a warning sign.
• Repair history for both systems.
• Well log (driller's report), if your state keeps them. It lists depth, casing, and yield.
• Past water test results.
• Any treatment equipment (softener, UV, filters) and its service history.

The septic inspection

Hire a septic professional for a dedicated inspection, not just the general home inspector. A proper inspection finds and opens the tank, measures sludge and scum, checks the baffles and any effluent filter, and looks over the drainfield for wet spots, odors, and surfacing effluent. Systems with pumps should have the pump, floats, and alarm tested. See septic inspections: what to expect.

Some states and counties require a septic inspection or certification when a property changes hands. Check with the local health department. Also check that the system's permitted capacity matches the number of bedrooms. A finished basement "bedroom" may not be counted.

The water test

Order a lab test from a state-certified lab. The sample should be collected by the inspector or the lab, not by the seller. At minimum, test what EPA recommends testing every year: total coliform bacteria, nitrate, total dissolved solids, and pH. Add anything the local health department says is common in the area, such as arsenic, uranium, radon, manganese, or fluoride, plus lead and copper if the plumbing is older. Use our test reader to read the report.

Look at the site

• Is the wellhead above ground, capped, and in a spot where water drains away? EPA says wells should be sited so rainwater flows away from them.
• How far is the well from the drainfield, including neighbors' systems? EPA notes most states set minimum setbacks.
• Is anything built, paved, or parked on the drainfield?
• Is there room for a replacement drainfield if the current one fails?
• Is it a dug or driven well? EPA notes shallow wells are more easily contaminated than drilled wells.

Questions to ask

• How many people lived in the house, and how often was the tank pumped?
• Has the drainfield ever been repaired or replaced?
• Has the well ever run dry or needed a new pump?
• Has the water ever tested positive for bacteria or high nitrate?

After you close

Start your own records folder, set reminders for yearly water testing and septic inspections, and work through our first-year checklists.

Other checks for the same house

Homes on private wells are often in areas with higher radon. See radon when buying or selling a home to add a radon test to the same inspection window. To work out how septic or well repairs should change your offer, use the pre-offer checklist.