The storm has passed, the street drain is already trickling, and the basement floor drain gurgles up something that is not rainwater. With basement sewage after heavy rain, the storm explains the timing. It does not explain where the pipe went wrong, and that is the question to settle first.
Pittsburgh Water explains that one pipe carrying sewage and stormwater together can push the mix into basements or up through manholes once it is overwhelmed. It adds that sewage backups happen when a private or public sewer is blocked, broken or overwhelmed by heavy rainfall or snowmelt, so melting snow can trigger the same thing.
DC Water's guide to sewer backups offers a helpful picture of why a basement is the exit. Because water seeks a level, the depth in the basement will be as deep as the height of the surcharge in the nearest combined sewer manhole, usually out in the street.
Gas without water is a separate question from a flooded floor; a rain-linked odor explained covers what the clue can and cannot show.
Not every wet basement is a sewage problem. Pittsburgh Water notes that stormwater can leak through gaps in the foundation, doors and windows. Etna's borough site describes a different route in a combined sewer community: during an intense rainfall, a connecting pipe can be overloaded, causing a backup into the basement through the floor drain.
Telling the difference by eye is risky. Pittsburgh Water warns that floodwater can be contaminated with oil, gasoline or sewage, and the CDC says floodwater can carry dangerous bacteria from overflowing sewage. Treat any storm water standing in a basement with the same caution.
If the water is not clearly from the drain, how to tell seepage, stormwater and sewage apart in a Pittsburgh basement goes through the clues and their limits.
One of the questions Pittsburgh Water puts to callers is whether the backup only occurs during a rain event. The answer helps the crew work out whether the sewer main or the lateral is the cause, and that decides who is responsible. The authority says that when a heavy-rain backup drains away after the storm, the property owner is responsible for cleanup.
Wondering whether the water downstairs is safe to stand in? The hazards agencies name for a flooded basement are electricity, contamination and wall pressure.
For the report itself and the neighbor check, the first-steps guide has the full list.
Pittsburgh Water recommends clearing debris from drains, gutters and downspouts, and says plumbing measures such as backwater valves or downspout disconnection must be considered case by case, since improper installation can make things worse. 3 Rivers Wet Weather adds that fixing improper connections to the sanitary sewer, such as downspouts and driveway drains, is the homeowner's job.
A related pattern shows up at the lowest drain in the house, which the page on a floor drain backing up in the basement takes apart.
Sewage Cleanup Crew, LLC refers homeowners to local cleanup contractors instead of doing the work itself. You can read how it works in the introduction on the homepage.
