Backed-up sewage is Category 3 water — it carries bacteria and pathogens, contaminates whatever it touches, and porous materials it soaks generally have to be removed rather than dried.
When you call, we connect you with a local specialist who will extract and dispose of the contaminated water and sanitize the area it reached.
Call now, or can it wait?
Call now if
Sewage is coming up through a floor drain, toilet or tub.
Several fixtures are backing up at the same time.
It has reached carpet, drywall or anything else porous.
It can usually wait for a scheduled visit if
One slow drain, with nothing backing up anywhere else.
What Suffolk County measures for sewage backup
Only 16 of the 155 areas we cover are mostly on public sewer, and 30 more are partly sewered, so a true municipal backup is a comparatively local problem in Suffolk County — elsewhere the equivalent failure is a cesspool.
Where there is a main, the split of responsibility matters: the lateral from the house to the main is the homeowner's, the main is the district's, and which one is blocked decides who pays.
Sewage Backup drivers across Suffolk County, town by town
Town
Areas
Sewered
Partly sewered
Unsewered
Babylon
13
7
3
3
Brookhaven
44
0
13
31
East Hampton
8
0
0
8
Huntington
20
0
4
16
Islip
23
7
5
11
Riverhead
7
0
2
5
Shelter Island
2
0
0
2
Smithtown
8
0
2
6
Southampton
20
1
1
18
Southold
10
1
0
9
Counts and medians of the areas we cover in each town, measured over developed land. An
area spanning two towns is counted under the first. Your own street can differ — each
area page has its own figures. Sources and limits.
What the sewage backup job actually involves
So you know what you are agreeing to, and can tell a thorough quote from a cheap one.
Stop water use and extract the backup.
Establish whether the blockage is in your lateral or the municipal main — that decides responsibility.
Remove contaminated porous material rather than drying it.
Sanitize, then dry to a measured moisture content.
Camera the line if it recurs, to find roots or a collapse.
Establish whose pipe failed before anyone quotes a repair. The lateral from the house to the main is yours, the main is the district's, and clearing a blockage is drain work — separate from extracting and sanitizing what came up inside.
What makes it worse
Cleaning it up without protective equipment. This is Category 3 water.
Drying carpet and pad that sewage has soaked instead of removing them.
Clearing the lateral repeatedly without finding why it keeps blocking.
Not reporting a rain-linked backup to the district, when the main is the likely cause.
Rules and programs worth knowing in Suffolk County
Backflow protection for basement fixtures
Suffolk County's sewer permit requires backflow preventers in areas connected to public sewers that are subject to backup, and New York's plumbing code requires a backwater valve on fixtures that sit below the level of the next upstream sewer manhole cover — which can include a basement bathroom or floor drain.
If a basement fixture has backed up, ask whether a backwater valve is fitted and whether it still closes — one fouled with debris does not seal.
The water-damage industry's standard, ANSI/IICRC S500, sorts water into three categories by contamination. Sewage sits in the worst, Category 3, which the standard describes as grossly contaminated and able to carry pathogens.
A backflow from a waste line beyond any trap counts as Category 3 whatever it looks like, so clear water rising from a floor drain is no evidence that it is clean. The category is set on inspection and shapes the scope of work; ask the specialist which one they recorded.
The CDC's advice for anyone cleaning up sewage is rubber boots, goggles and gloves, and a waterproof bandage over any cut or wound first. If you would rather not handle it at all, that is exactly the work a specialist is for.
Sewer backup is commonly excluded on a standard homeowners policy, and is usually only covered with a specific water backup endorsement. If the fault is in the municipal main the district may be liable, which is another reason to report it rather than only clear it.
General guidance, not advice on your policy — coverage varies by insurer and endorsement, and
the wording is what decides it. Read yours, or ask your agent, before you need to.
If the basement bathroom pump failed
A basement toilet, shower or laundry sink sits below the pipe that carries waste out of the house, so it drains into a sealed basin and a sewage ejector pump lifts the waste up to that pipe. It is not the sump pump: a sump moves groundwater and rain, an ejector moves sewage.
A basement toilet or shower backing up while the fixtures upstairs drain normally
An alarm sounding from the basin, where one is fitted
Sewage odor or a wet floor around the sealed basin lid
The pump running without stopping, or staying silent, when a basement fixture is used
Stop using the basement fixtures and anything else that drains into that basin, and keep people and pets away from what has come up. Treat it as sewage: it is Category 3 water, and what it soaks generally has to be removed rather than dried.
Signs you need sewage backup help now
Sewage or dark water rising from a basement floor drain
Several fixtures backing up at once rather than just one
Toilets bubbling when a sink or washing machine drains
Sewage odor indoors with no obvious source
Backups that recur after heavy rain
What to do before help arrives
Worth doing whether or not you call us.
Stop running water immediately, including appliances on a timer.
Keep everyone out of the affected area — this is Category 3 water, not dirty water.
Do not attempt to clear it with a plunger or a drain chemical if several fixtures are affected at once.
Note whether it followed heavy rain. That single detail usually says whether the fault is yours or the district's.
Photograph the extent before cleanup for the insurance claim.
How to keep it from happening again
Nothing but toilet paper down a toilet — including wipes sold as flushable.
Put cooking grease in the trash, not the sink.
If the lateral has backed up before, have it camera-inspected for roots or a sag.
Ask about a backwater valve on basement fixtures.
Report a backup that follows heavy rain to the sewer district.
Sewage Backup: common questions
Is the problem my line or the whole street?
If only the lowest drain in your house is backing up and it gets worse when you run water, the blockage is most likely in your own line. If neighbors have the same problem at the same time, or it backs up with nothing running in the house, the main is more likely. Tell the specialist which, because it changes the first call to make.
Is it safe to stay in the house?
Keep everyone, especially children and pets, away from the affected area, and do not use the drains until the line is cleared. If the backup has reached living space or the heating system, or anyone feels unwell, stay somewhere else until it has been cleaned.
Should I pour drain cleaner in?
Not for a sewer backup. It rarely clears a blockage in the main line, and it leaves caustic water in the pipe and on the floor for whoever clears it next. If you have already used some, say so when you call.
Why does my house smell like sewage when nothing is backing up?
Most often it is a dry trap. Every drain holds a little water in a U-shaped bend that blocks sewer gas, and in a floor drain or a sink that is rarely used that water evaporates. Pour a quart of water down each unused drain. If the smell stays, the usual causes are a failed wax seal under a toilet, a blocked roof vent or a cracked drain line, and those are a plumber's job. A smell together with dark water at a floor drain is a backup starting.
Sewage is coming up in the shower or bathtub. What does that mean?
The blockage is in the main drain, past the point where that fixture joins it, so waste comes out at the lowest opening in the house. That is usually a tub, a shower or a floor drain. Stop using water everywhere in the house, because every flush and every load of laundry comes up in the same place. This is a main line problem, not a tub clog.
Who do I call for sewage in the house?
There are two jobs. A plumber or drain company clears the blockage, and the sewer district is the call if the main in the street is the cause. What came into the house is a separate cleanup: material that sewage soaked is removed and the area is sanitized, which is the work of a sewage cleanup specialist. If sewage is already on the floor, the cleanup should not wait for the drain repair.
What decides the cost of a sewage cleanup?
How far it spread and what it soaked. Sewage on bare concrete is extraction and sanitizing. Sewage in carpet, drywall or insulation means removing and replacing them, and on a finished basement that is most of the job. How long it sat matters as well. We do not quote prices; the specialist who sees the job does.
Local conditions change what causes this and how it behaves, so each area where the
drivers behind sewage backup are actually present gets its own page with that
area's measured data. 15 of the 155 areas we cover
qualify; 13 of those pages are published so far and the rest are being added.