The Reason Your House on a Hill Might Still Need a Sump Pump

"My basement sits on a hill or slope, so the water will run downhill."

Water generally runs downhill, but not always.  For example: if you poured out a glass of water onto a solid surface, the water would run in whichever direction was lower than where you poured it.  However, if you poured out the same glass of water onto a sponge, the sponge would first absorb a good amount of the water as it passed through the sponge.

Some homeowners believe that because their house rests on a hill or slope, rain and groundwater will automatically run downhill every time.  The loophole in this theory is the soil around your home.  Soil acts more like a sponge than a solid surface, especially the soil around the perimeter of your home.

When your home was built, the first phase of construction included excavation.  The builders essentially dug a hole in the ground to construct your foundation, and they backfilled the remaining gap with loose soil.  This soil is not nearly as compacted as the surrounding soil that has been in place for thousands of years, so it absorbs water more easily.  When it rains, the water actually soaks into the loose soil first.  Runoff only occurs at the point in which there is an excess of water—more water falling or filling the space than the soil can possibly absorb.  Otherwise, the water saturates the loose soil around your home like a sponge.

For all of the rainwater to run downhill, the whole surface area around the perimeter would have to be a solid.  Unfortunately, your home sits in more of a clay sponge.  So, you need a way to get the water out and away from your basement.  The only reason your house on a hill doesn't need a sump pump is if you don't want to keep your basement dry! 

As expert basement waterproofers, we encourage all homeowners to call and ask for a free basement waterproofing estimate.  Our experts will diagnose the lay of the land and soil around your home and offer a unique and customized waterproofing system.  This system will direct water away from your basement by use of a perimeter drainage system tied into a powerful sump pump.  A home free of water is a more comfortable, and healthier home for the whole family to enjoy!