Water usually comes into the basement from two sources:
Through windows, walls, and floors. If you don't have adequate drainage or grading around a home, the storm water will seep through those surfaces. Also, flooding may be contributed to malfunctioning sump pumps or drains (foundation or gutter).
Through sewer backups from the basement drain. If you live in an older area, a wet weather for a few days may carouse flooding. A sanitary sewer creates surcharges from inflow and infiltration (sometimes referred to as "I/I") when ground or rain water enters the sewer system through cracks in home sewer pipes. Among other causes are sewer blockages from grease, tree roots, debris, and deteriorated conditions in a city or home sewer line.
You need to call your city or town's Sewer Maintenance Operations Center. Though the problem may turn out to be in the private property line (responsibility of the owner), it is best to call the city first to check the public system.
If you live in a city setting, here are most common actions performed by the municipality to remedy the problem of aging sewers:
Inflow and infiltration sewer studies have been conducted in various older neighborhoods;
Capital Improvement Projects are normally identified as a result of the sewer studies. Solutions may include refurbishing older sewers by employing trenchless technology such as cured-in-place-pipe, sewer replacement, or adding additional/larger sewers to increase capacity.
Ongoing capacity studies to determine additional capacity needs. Additional capacity studies will be prioritized pending the acceptance of local authorities.
If your home was built prior to 1963, please check your downspouts to ensure they are not still connected to the sanitary sewer, which is now prohibited by city code. They should drain directly into the street or yard. Roof and foundation/footer drain connections add excess water to the sewer system.
Take a good look at the drainage system at your property. Ensure proper functioning of your sump pump and drainage system around the house. Clean your gutters and monitor them to ensure they are free of debris.
Run water from a hose through your home drains to check for blockages and ensure water is draining properly. Don't forget to check the grading around your home to make sure water is being directed away from the structures. If you notice "ponding" in the yeard, fill those and any other low spots.
To prevent sewer blockages, never dump grease, paint, or other thick liquids into your sinks or drains. Never flush items not suitable for sanitary sewer disposal, like paper towels, diaper wipes, contraceptives, and feminine products.
Make sure to verify with your insurance carrier if you have flood and sewer backup coverage, especially if you have a finished basement. This coverage may require a separate rider to your policy.
When you buy or rent a home, ask whether it is located in a flood plain or flood-prone area. Homes at lower elevations and those with depressed driveways are more likely to experience flooding problems.
If a sewer backup occurs, proper cleanup procedures must be followed for safety reasons. Never enter a flooded basement because the risk of electrocution is present. You must wait for the water to recede.
If you have a mature tree in the vicinity of your sewer line, consider removing the tree to avoid future problems with root invasion.
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