Drainage Problems

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As we can see in the image above, this crawl space is very wet! This condition is the result of the soils inability to drain ground water fast enough resulting in a high water table. Professional drainage contractors will typically install a perimeter drain system in the crawl space 10 – 12 inches deep near the footings to collect water and route it to a reservoir at a low area where a submersible pump with a float valve then ejects the water. Once the float valve rises to a level that turns on the pump to a designated exterior location.

A proper installation is imperative for longevity. Four inch perforated flexible pipe encased in a filter “sock” should be installed in a trench dug along the entire perimeter. The trench should be large enough to add a layer of drainage rock beneath the pipe as well as over the pipe in order to keep the filter from being clogged with soil. Once the system is installed, a water alarm and probe can ensure the occupant is alerted if the pump fails for any reason.