Why Main Sewer Lines Back up During Hail Storms

Hail storms bring intense rainfall that hits the ground faster than the ground can absorb it. In a hot, dry climate with occasional spring thunderstorms, the downpour can be sudden and heavy. Storm drains and sewer lines are designed for average rainfall, not the extreme volumes a hail storm can produce. Even in arid regions, these storms can overwhelm the system.

When the public sewer system reaches capacity, water backs up into the lowest points, including your home's main sewer line. The pressure can force sewage up through floor drains, toilets, and sinks. If your line is older or has cracks, the problem becomes worse.

Your main sewer line connects your home to the public system. If the public line is full, your line becomes the escape route for excess water. The slope of your pipe and the location of your cleanout determine where the backup appears first.

Older homes in areas with shifting soil may have pipes that settle or crack over time. Stormwater seeps into these cracks, adding to the flow. The result is a backup that can flood your bathroom or lower-level rooms with contaminated water.

A backwater valve can prevent sewage from flowing backward into your home, but it requires professional installation. Ask a plumber about your options. Regular maintenance of your line, including removing tree roots and debris, helps keep it clear.

After a storm, remove any visible debris from your cleanout and yard drains. The pros can inspect your line and recommend repairs if needed. A small investment in prevention can save you from a major cleanup later.