After 4 inches of rain on February 7, a student contacted me in an agitated state of mind. “Our basement is flooded, the internet is out, I can’t do my homework and the repair crew hasn’t shown up yet,” the message read. Estimated cost for the remedial work turned out to be $4,000, including a French drain, coating the wall, and building a drain sump along with an electric pump. Not surprisingly, my son reported the same day that his own crawl space was under water. The same estimate followed soon afterward.
The proposed solutions were a professional approach. But after much experimentation with perforated drain pipes, gravel-lined trenching and other remedies on my own property I concluded that one needs to take a wider view of the problem. Early trials with black corrugated pipe revealed only that dirt and plant roots love to settle in there, clogging the whole system in a short time.
The troublesome water that used to produce small rivers in the basement didn’t originally come from the soil. The previous owner had tried to stem the steady flow that penetrated the cinderblock walls with waterproofing paint. That product can seal a little crack in the floor. But it is no match against the hydrostatic force of a 6-foot column of water, pressing from the saturated soil into the basement wall. Some time spent outside in the pouring rain showed that the water was coming from the roof. Damaged gutters and undersized 3-inch downspouts were creating nasty waterfalls, soaking the ground immediately next to the house. After replacing the gutters and installing 4-inch downspouts, it was important to not even let that water enter the ground nearby. To prevent accumulation of dirt and roots, I used smooth 4-inch PVC pipe, making a storm sewer running underground on both long sides of the house. Every downspout drains into that, with a final exit in the back yard 150 feet from the structure. Along with some minor re-grading to ensure that the ground slopes away from the building in all places, this simple gravity-based system turned a very wet basement into a completely dry one.
Drain sumps and pumps work, but all pumps fail eventually. The failure notification will be another flood. Working towards a dry basement and crawlspace needs to start at the roof and the gutters.
Rudi Kiefer, Ph.D., is a professor at Brenau University, teaching physical and health sciences on Brenau’s Georgia campuses and in China. His column appears Sundays and at gainesvilletimes.com.