A sewer scope before you buy an older house
Updated October 30, 2026 · 3-minute read · Old House Sewer Lines
A sewer scope inspection before you buy records the inside of the house's sewer lateral on video, so you know its material, its condition and its defects before the pipe becomes yours. In southern Westchester the lateral is generally the owner's responsibility, and repairs to it are not cheap.
The county's wastewater division puts it simply: the house line feeding the street sewer is for the property owner to look after, while the local municipality owns and runs the main (Westchester County DEF). Mount Vernon says the owner is responsible from the property to the connection with the city sewer and that it has no lateral replacement program. Yonkers says many homeowners are responsible for the sewer service line between home and city main. Elsewhere, no published wording could be confirmed here; the town's engineering or public works office can say where the owner's share ends, and lateral ownership has the background.
Where a sale already requires video
Two municipalities have confirmed point-of-sale laws. In the Village of Mamaroneck, an owner must obtain a discharge compliance certificate before a title transfer or a permit for work worth more than half the assessed value. The plumber, licensed in Westchester County, must supply a CCTV video record of the entire lateral and confirm that no leaders, pumps or drains discharge into the sanitary sewer (Village of Mamaroneck Code). A certificate can stand for up to 10 years if nothing significant has changed; the village form lists a $150 fee. If repairs are needed, the closing can go ahead with money held in escrow and the work done within six months.
Rye adopted a similar law in May 2021 and began enforcing it on January 1, 2022. Its waiver window is five years rather than ten (City of Rye). Scarsdale and the Town of Mamaroneck may have sale-time rules as well, but this site could not confirm them from the official text; check with the building department. Full detail is in selling a house: sewer lateral certificates.
What to ask for
In towns with no sale law, the scope is the buyer's choice. Ask for these items:
- The complete video file with a running distance, not a handful of still images.
- Where the camera entered, how far it went, and why it stopped.
- The pipe material along the run and where it changes.
- Findings logged by distance, ideally using NASSCO's coding system for laterals.
The common lateral faults EPA lists are a useful checklist: improper connections, faulty joints, roots, poor bedding, aging pipe material and broken cleanout caps (EPA). Reading a sewer inspection report explains the format.
Why older houses deserve the extra step
FEMA observes that older homes are often served by clay or cast-iron laterals. The clay pipe industry itself warns that joints in pipe laid more than seven decades ago were often made on site and may not satisfy today's standards, and that pipe from before the 1950s can be weaker (NCPI). A house of that age may also still have a house trap, which the state code now prohibits in new work; see the house trap. None of that means the line is failing. It means the video is worth having before the price is settled.
Who does it
Camera work on a sewer line is contractor work. The sale laws in Rye and the Village of Mamaroneck require a plumber licensed in Westchester County, and the county's consumer protection department advises asking to see the plumber's Westchester licence card. A seller's report is a starting point; a buyer may want a separate scope.
Video from NASSCO Inc., an outside channel: A Northern Virginia realtor explains why buyers of older homes should get a sewer scope from a certified inspector. Nothing loads from YouTube until you press play.
Key facts
- County wastewater officials assign the house lateral to the owner and the street main to the town or city (county DEF).
- The Village of Mamaroneck requires a CCTV video of the entire lateral for a discharge compliance certificate before a title transfer (Chapter 282).
- A Village of Mamaroneck certificate can be relied on for up to 10 years; Rye's window is 5 years.
- Rye's point-of-sale law has been enforced since January 1, 2022 (City of Rye).
- Both laws require the certification to come from a plumber licensed in Westchester County.