Cesspool Removal and Replacement in Plymouth, MA

What a Cesspool Actually Is

A cesspool is a covered pit, usually lined with brick, block or precast concrete, that receives raw sewage directly from the house and lets it seep into the surrounding soil. There is no septic tank ahead of it, no distribution box and no leaching field. Solids settle at the bottom and liquid escapes through the walls and floor.

That is the entire design, and it is why the state stopped permitting them. A modern septic system settles solids in a watertight tank and then distributes the clarified liquid across a properly sized leaching area, where soil treats it before it reaches groundwater. A cesspool skips the treatment step. In a town like Plymouth, where a great many homes draw drinking water from private wells, that matters.

Cesspools turn up regularly in homes built before the 1970s. Plenty of owners have no idea they have one, because a cesspool that is pumped occasionally can run for decades without complaint. It is usually the Title 5 inspection that reveals it.

In Plymouth, a Cesspool Is an Automatic Failure

This is the part that catches people. Plymouth no longer allows cesspools, and a cesspool or cesspit found at the time of a disposal system inspection constitutes an automatic failure. Not a conditional pass. Not a recommendation to monitor it. A failure.

Condition is irrelevant. A cesspool that has never backed up, never smelled and never given a day of trouble still fails, because the finding is the failure. Homeowners argue this point with inspectors every year and the answer does not change.

Plymouth is not alone. Pembroke voted on May 6, 2019 to make cesspools an automatic fail on conveyance of property. Duxbury treats them as automatic failures as well. Under state Title 5, cesspools must also be upgraded when they show signs of hydraulic failure, sit too close to a water supply, or when design flow increases because a bedroom is added.

Do You Have a Cesspool?

• Check the age of the house. Homes built before the early 1970s in unsewered parts of Plymouth are the common candidates.
• Look for an as built plan. Plymouth keeps septic as built plans and permits on file, available through a public records request. If there is no plan on record for a house of that age, a cesspool becomes more likely.
• Count the covers. A conventional system usually has a tank with two access points plus a distribution box. A single round cover with nothing else nearby often indicates a cesspool.
• Ask your pumping company. Whoever has been pumping it knows exactly what is down there.

If you are even reasonably sure you have one and you are thinking about selling, find out now rather than three weeks before closing. The timeline for replacement is measured in months, not days.

Replacing a Cesspool With a Septic System

Cesspool removal is not a standalone job. You are not removing a cesspool so much as replacing it with a compliant septic system, and the sequence is the same as any septic system replacement:

1. Soil evaluation and percolation test to establish soil conditions and seasonal high groundwater. This is the longest lead item and it is seasonal.
2. Engineered design sized to your bedroom count and lot constraints.
3. Board of Health review and permit. In Plymouth this runs through the City Hall Systems portal.
4. Installation of tank, distribution box and leaching area, with staged town inspections along the way.
5. Decommissioning the cesspool. It has to be pumped, then either removed or crushed and filled so it cannot collapse later or receive flow again.
6. As built plan and Certificate of Compliance filed with the town.

That decommissioning step is not optional and it is worth insisting on. An abandoned cesspool left intact under a lawn is a collapse hazard, and it will show up on a future inspection.

If the Lot Will Not Take a Full System

Cesspools tend to sit on older, smaller lots, which is exactly where a fully compliant system is hardest to fit. Where full compliance is not feasible, the Board of Health can grant a Local Upgrade Approval, bringing the system as close to compliance as the site allows under defined minimum criteria. On a constrained Plymouth lot this is often the path that makes the project affordable, and many homeowners are never told it exists.

Ask the Board of Health about it directly, and ask your engineer whether it was considered. Note that in Plympton, alternative and innovative systems have not been permitted since March 9, 2021, so that particular workaround is unavailable there.

The Massachusetts septic tax credit applies to cesspool replacement as well, provided the property is your owner occupied principal residence. Confirm the current figures with the Department of Revenue before budgeting around them.

Common Questions

Can I sell a house with a cesspool in Massachusetts?

A sale may be possible, but the inspection outcome and upgrade requirements depend on state failure criteria and local regulations. Plymouth treats cesspools as failures at inspection; that is not a blanket statewide rule for every cesspool. Confirm the required work and deadline with the Board of Health, and any closing arrangement with your attorney and lender.

My cesspool works fine. Do I still have to replace it?

If you are not selling and it is not failing, you are generally not forced to act immediately. At transfer of title in Plymouth it is an automatic failure regardless of condition, and adding a bedroom or any increase in design flow also triggers the upgrade requirement.

Is a cesspool the same as a septic tank?

No. A septic tank is watertight and settles solids before passing liquid to a leaching field for soil treatment. A cesspool is a pit that discharges directly into the ground with no treatment stage. People use the terms interchangeably, but Title 5 does not.

How long does cesspool replacement take?

Several weeks to a few months, driven by perc test scheduling, engineering and Board of Health review rather than by the excavation itself. If a sale is involved, start the moment you suspect you have a cesspool.