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Basement flooding is expensive and a worry or dread during heavy rains especially to home owners with finished basements. Taking some time to learn the causes of flooded basements and to think about it a little should bring some relief.

Common Causes of flooded basements

There are definable causes that result in flooded basements. It is possible to prevent your basement from being flooded. Basements often flood due to one or more of the following common causes. Common causes of flooded basements, sorted by most common to least common are:

  1. Overflowing gutters: obstructed gutters, toys in guttesr, plugged downspout (leaves, toys, tennis balls), clogged downspout elbows backing water up, gutter covers that are too restrictive, bad design or are clogged themselves
  2. Gutters channeling water into a downspout that doesn't go into a drain or has been disconnect by a drain during contruction, remodeling etc (example, drain going through a deck and then dumping it's contents under the deck where you cannot see it and the contractor never connected it back up properly)
  3. Old, rotten drain lines that have collapsed or have partial to complete blockages
  4. Plugged drain line (leaves, needles, sticks getting into drain and blocking drains at sharpest elbows
  5. Surface water from neighbors flowing onto your property towards your basement
  6. Surface water and mole tunnels that are funneling surface water to a point right outside your basement. Moled tunnel through moist soil to get worms and grubs.
  7. Full "dry" well
  8. Blackwater or graywater sewage line in older house rotting through and welling up in and under the concrete floor. You can lightly (or as hard as you wish) tap around wet spots (source of water) on a foundation floor. If you do this, a part may cave in and reveal the leaking pipe imbedded in the concrete (I've seen and done this). If the pipe is broken and leaking under the floor, then you may need someone with a scope to put it down the sewer pipe to see where a rotten/caved-in pipe is located.
  9. Backed up city sewer lines (not really common thankfully, because what would you do?)
  10. House sliding down hill, house jacked up by dirt pulled drain lines away from downspouts
  11. Soil around foundation settling and pulling drain line away from the downspout
  12. Gutters pulling loose from roof edge and rain water missing the gutters. Or worse yet, gutters falling off the roof line or kinking.
  13. Plugged downspout falling off the house
  14. Overflowing rain barrel(s)
  15. Gutter rotten completely through

Identifying which causes of basement flooding that you are most likely to experience and taking steps to remedy the situatins(s) will help you prevent a flooded basement and the expense and agony that goes with this.