Gwinnett County is Grayson's water utility, and city records show the city's sewer extensions connecting to the Gwinnett County system, though some properties may not be on municipal sewer. Either way, the drain pipe leaving the house is the owner's, and it's what a plumber repairs. Call the number on this page to be connected with a local plumber in Grayson.

Who provides sewer in Grayson?
The city's community links page names Gwinnett County as the water utility, and the city has no water department. No city page states the residential sewer provider outright, but a city solicitation to extend sanitary sewer through Grayson Industrial Park says the line connects to the Gwinnett County system and needs Gwinnett DWR approval. Some properties may not be on municipal sewer and use private onsite systems instead. Your bill is the quickest check: a Gwinnett sewer charge means you're connected. Gwinnett's 24-hour dispatch is 678.376.7000, and Gwinnett's guidance puts all plumbing between the meter and the home on the homeowner.
Why would a new Grayson house have a sewer problem?
Grayson grew from 765 residents in 2000 to 4,730 in 2020, and its housing is among the youngest in the metro, with a median build year around 2012 and fewer than 4% of homes from before 1980. Nearly every drain line is PVC. It won't corrode, but it can develop a low spot where trench backfill settled, crack under a driveway, or pull apart at a joint when a fence, pool or irrigation line goes in. Construction traffic during later phases of a subdivision can also crush shallow pipe. Watch for gurgling toilets, water rising in the lowest tub and drains slowing throughout the house.
Who handles permits?
The City of Grayson takes building permit applications through its own online portal from City Hall on Grayson Parkway, and its inspection process directs scheduling to 770-338-8000. Whether plumbing-only repairs go through the same portal wasn't stated, so ask your plumber to confirm with City Hall at 770-963-8017.
A local note
On a house only a few years old, check whether any builder's warranty still covers the drain line before paying for a repair. A camera inspection gives you the evidence either way: it shows the defect, its depth and whether it looks like settling or later damage. Before the plumber arrives, stop running water, find the cleanout near the foundation and note when the problem began, especially if it followed work in the yard.
Sewer Line Repair questions in Grayson
Can the sewer line under a fairly new house still fail?
My home isn't on municipal sewer. What line could a plumber still repair?
Does sewer line work need a permit here?
Why does the plumber want to run a camera before quoting a repair?
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