The street sewer backed up into my house. What is a backwater valve?
Sewage came up through the basement floor drain, or a low toilet or tub gurgled and overflowed, during a storm or a heavy-use evening.
The usual cause is the municipal main in the street filling past capacity, called surcharging. With nowhere to go, the flow pushes back up the lateral and out of the lowest opening in the house.
A backwater valve, also called a check valve, is a fitting on the lateral or building drain with a flap that lets waste leave and shuts when flow reverses. It sits on the line ahead of the branches serving the lowest fixtures.
Fitting one is not a quick swap. It usually means opening the floor or digging to reach the pipe. What it involves depends on access, the depth of the line, the valve and materials, how much has to be opened up and restored, and whether a permit or code sign-off is required. Rules vary by area.
A valve does not fix roots at a clay joint or a bellied line holding water. It only stops reverse flow. A private line problem needs a camera inspection first, then a cable machine or hydro jetting depending on what the camera shows.
Street or private? Ask three things. Are the neighbors affected? Did it coincide with heavy rain? Is only the lowest opening backing up while upper fixtures drain normally? Yes to those points to the street main. Only your house, in dry weather, points to your own lateral.
Safe homeowner check: look at the neighbors and the forecast. Stop running water now: no flushing, washer or dishwasher. Keep people and pets out of contaminated water, and call.
Expert Plumbers Co is a referral service. We connect you with an independent local plumber in Perham, MN. Call (380) 262-9173.
After the cleanup, ask how the valve will be kept working. The flap and its hinge can be stopped by lint, grease and grit, and then it no longer seats fully. Most valves have an access cover so the flap can be looked at and cleaned, and that should be done on a routine, not only after a storm. Learn where the cover is and keep boxes and floor coverings off it.
One point catches people out. With the valve closed during a storm, your own household water has nowhere to go either. Showers, sinks and the washer will fill the line behind the flap, so keep water use low until the street main drops.
After any backup, the floor drain and the area around it need to be cleaned and disinfected. Porous materials that soaked up sewage, such as carpet pad and cardboard, usually have to be removed rather than dried.
Small flies keep coming out of the drain. Is that a clog?
Possibly, but not always. Small flies rising out of a drain are drain flies. They breed in the organic film that coats the inside of the trap and the first few inches of pipe, not in clean standing water. The film is the nursery.
A slow or partly blocked drain gives that film somewhere to sit, which is why flies and a slow drain often show up together. A drain nobody uses is a different case. When its trap dries out, flies and sewer odor both come straight up the pipe.
Safe homeowner check. Tape a card or a clear bag over each suspect drain overnight. Flies on the underside show which one they come from. Clean the strainer and the visible part of the drain. On a rarely used drain, pour in a bucket of water to refill the trap.
A cable machine is enough when one fixture is slow and no flies are involved. A cable only cuts a channel through the blockage and leaves the film on the pipe wall. A line that keeps producing flies after cleaning usually needs hydro jetting, which strips the wall back to bare pipe.
One fixture is a local job. Flies plus several slow drains point further down the line: grease build-up on the pipe wall, a bellied section holding water, or root intrusion at a joint. That calls for a camera inspection before anyone picks equipment.
Stop running water and call if drains gurgle, sewage odor fills the room, or water rises in the lowest fixture.
Expert Plumbers Co is a referral service. We refer homeowners in Perham, MN to an independent local plumber for Drain Cleaning. Call (380) 262-9173.
The choice of cleaner matters. Bleach poured down the drain kills flies on contact but leaves the film they feed on, so they return within days. Boiling water helps on metal pipe but can soften or loosen joints on some plastic, so use hot tap water. A stiff brush on the strainer area and the first few inches of pipe does more than any liquid. An enzyme cleaner left overnight can digest the film, but treat it as upkeep, not a cure for a blocked line.
Check the overflow opening on sinks and tubs too. That channel is rarely cleaned and can breed flies.
Adult drain flies are weak fliers and rest on walls near the source, so counting them each evening shows whether cleaning is working. If the numbers do not fall within a week of thorough cleaning, the source is deeper in the line, or in a seldom-used floor drain in a basement or utility room that nobody thinks about.
Our older house has a house trap, or running trap, in the basement. Why does it keep clogging?
Your basement drain backs up every so often, and each time someone points at the house trap and clears it again. In an older house that is a familiar story.
A house trap, also called a running trap, is a U-bend on the main drain near the foundation wall, with two cleanout plugs. It holds water to keep sewer air out. The trouble is that the dip slows the flow and gives solids a place to settle. Paper, grease, wipes and roots that pass through a straight pipe pile up in the bottom of the bend, so the trap becomes a frequent stoppage point.
Old lines make it worse. Scale in cast iron roughens the pipe and catches debris before it reaches the trap. Root intrusion at a clay joint outside sends fibres toward it. A bellied line downstream can hold water back so the trap never fully clears. Many traps were removed over the years, and local code on keeping or removing one varies.
One slow fixture is usually its own branch problem. If toilets, tubs, sinks and the washer all slow down together, or the floor drain bubbles, the trap or the main beyond it is the likely spot.
Safe homeowner check: Stop using water and look at the two trap plugs without opening them. Check whether the floor drain is holding water, and note which fixtures back up first.
Stop running water and call now if sewage is coming up from a floor drain or shower, if you smell sewage in the basement, or if a plug is weeping. Never loosen a trap plug under pressure, because sewage can surge out.
A cable machine is often enough to clear the trap itself when the stoppage is soft. Hydro jetting is the better choice when grease or scale lines the pipe on either side. A camera inspection is the right step when the trap keeps clogging, because it shows whether the real fault is a belly, a root-filled joint or a failing section further down.
Expert Plumbers Co is a referral service. We connect you with an independent local plumber in Perham, MN. Call (380) 262-9173.
Ask whether the trap can stay and be cleaned when needed, or be removed where code allows. The scope depends on basement access, the condition of the pipe on both sides, how much floor has to be opened up, and any permit or code requirement for changing the main.
Our cabin or second home sat empty for months and now the drains smell and run slowly. Why?
You open the cabin for the first time in months and the drains smell like a sewer and the water creeps away.
Every fixture has a trap, the curved section that holds a little water to block sewer gas. With no use, that water evaporates. Once the seal is gone, gas comes straight up the drain. The film left in the pipe also changes while the house sits. Soap, grease and food residue dry and harden on the pipe wall, so the first heavy use narrows the line and water slows down. Then there is the line itself. A vacant house can still have roots working into a clay or cast iron joint, and nobody was flushing them back with daily flow.
If one sink or tub is slow and the others are fine, the problem is probably local to that fixture, its trap or its branch line. If every drain is slow, several fixtures gurgle, or the toilet bubbles when you run the washer, the blockage is further down, in the main line or the lateral to the street.
Safe homeowner check: run water in every fixture for a couple of minutes, including rarely used ones, to refill the traps. Pour a cup of water into floor drains. If the smell fades and the flow picks up after a day or two of normal use, dried traps and loosened residue were likely the whole story.
Stop running water and call now if wastewater comes up in a tub, shower or floor drain, if the toilet will not clear, if the smell stays strong after the traps are filled, or if you see wet floors, stained ceilings or sagging drywall.
A cable machine is enough when the clog is residue or a soft plug in one branch. If the line stays slow after cabling, if roots are suspected, or if grease has coated the full pipe wall, the plumber will usually recommend hydro jetting, which scours the pipe wall with high pressure water. A camera inspection settles the question of roots, a belly holding water, or a failed lateral.
Expert Plumbers Co is a referral service. We connect you with an independent local plumber in Perham, MN. Call (380) 262-9173.
Before you book, tell the plumber how long the house sat empty, whether it was winterized, and which drains are affected. Ask whether they plan to cable, jet or run a camera first, and what they will do if the camera shows roots or a damaged section. The scope depends on access to the line, the parts or pipe needed, how much has to be opened up, and whether a permit or code step applies to a repair.
The city is replacing the street main outside our house. Why are our drains acting up now?
The crew has been digging up the street for a week, and now your toilets gurgle, the tub drains slowly, or you saw muddy water in a floor drain. It is natural to suspect the work outside. There are a few real reasons why it can be connected.
Your house drain, called the lateral, runs from your foundation to a connection on the city main. When the main is dug up and replaced, that connection is cut and reattached. Vibration, trench work and heavy equipment can crack an older clay or cast iron lateral, push a joint out of line, or shift the pipe so water now pools in a low spot. Dirt, gravel and construction debris can also wash into the line while connections are open. The work can also cause temporary backups while flow is being rerouted or the new pipe is flushed.
The key question is whether it is one fixture or the whole house. A single slow sink is probably the fixture. If every drain is sluggish, gurgling or backing up at once, particularly the lowest ones, the trouble is in the lateral or the main, and the street work is a likely suspect.
Safe homeowner check: write down when the symptoms began and compare that to when work started near your address. Take photos of any muddy water, debris or wet floor. Check whether neighbors have the same trouble. Run one tap for a minute and see if the lowest drain in the house reacts.
Stop running water and call now if sewage is coming up in a tub or floor drain, if there is standing water in the basement, or if you smell sewage inside the house. Do not keep using the washer or dishwasher.
Tell the utility or the contractor promptly. They may have a claims process, and a delay can make it harder to show when the damage started. A cable machine may be enough if loose debris is the problem. If the lateral is cracked, offset or holding water, the plumber will need a camera inspection to see the damage, and hydro jetting can flush out silt and gravel.
Expert Plumbers Co is a referral service. We connect you with an independent local plumber in Perham, MN. Call (380) 262-9173.
Ask the plumber to record the camera inspection and write down the footage location of any damage, so you can give it to the city or contractor. Scope depends on how deep the pipe is, how much has to be dug up or opened, parts and materials, and any permit or code requirement. Responsibility for the repair varies by area, so confirm who owns which section of the line.