I am looking for someone to fix a basement problem in our 1966 home. We now have a sump pump in the basement but when we first moved here in 1975, we had a submersible pump. Every now and then it would stop working and our basement would flood, a disaster every time. We finally dug a ditch in the basement next to the wall, but it only reaches halfway around the basement between the stairs and the pump.

We have talked for years about finishing the basement so we could have a drain to the pump but could never figure out how to do it. The house has rain gutters on the front and back but not on the sides. Our deck extends over most of the back of the house, and we were told that we would need to remove part of it so we could dig down next to the southwest corner of the house (where we still have a water problem) and install a drain system.

We have removed the deck nearest that corner but now we need someone to help us put in the drain, finish the drain area in the basement, and close it up so the basement is usable.

Any help you could provide would be deeply appreciated.

It's taken longer than I anticipated to get back to you about your project, but I've finally located a contractor who specializes in situations similar to yours.

The contractor tells me he has visited your home to inspect the problem. He says it's not unusual for homes in this area to experience water leakage into the basement because of the high water table. The water builds up against the basement concrete wall, and it's likely then to penetrate weak points. Typically, weak points are found between the footing and the foundation, under the footing where it comes up between the foundation wall and concrete floor, and cracks in the foundation itself.

The normal fix would be to install a French drain around the property. In your situation, because of the terrain, landscaping, and deck, it would be a costly project.

A French drain carries excess water from a low point or areas prone to saturated soil away from the home. Typically the system is installed at the lowest point (footings) near the perimeter of the building or wherever standing water is found. It consists of a trench filled with pea gravel or round rock, topped with coarse sand, and then covered with soil to make it less conspicuous. French drains must slope downward (1/4 inch per foot) because they depend on gravity. However, they can also include a drainpipe that directs water away from the perimeter with a pump system.

In your case, the contractor recommends a drainpipe inside the home in a French drain design installed near or under the footings. The trench needs to be about 12 inches wide to accommodate a 3-inch drainpipe. Because there will be a riser at one end of the system, the drainpipes can be placed level in the trench. Once the pipe fills with water, the water will flow automatically toward this riser to the sump pump, which will pump it out.

Fill the bottom of the trench with approximately 3 to 4 inches of 1 1/2-inch round rock.

Then center 3-inch perforated drainpipe in the trench with the holes pointing down and connect it into the riser. Use more 1 1/2-inch round rock to fill the trench on both sides of the pipe and cover the pipe with another 1 1/2 inches of rock.

Next cover the rock with a filter fabric, such as Typar, which will allow water to flow freely through the rock and—most important—reduce the buildup of silt (fine sand particles) in the system. Finally, fill the trench with coarse sand, leaving enough space on top for concrete to match the finished thickness of your existing floor.

I'm told you have a load-bearing wall on a footing in the center of the basement. This, too, needs drainpipes on both sides of the footing with all drain lines tying back into the perimeter system with long-sweep "Y" elbows. Even though you already have a sump pump in the center of the room to tie the system into, it would be better to drain the water to a 36-inch high by 24-inch round perforated riser in the southwest corner of the basement near the highest concentration of water.

Install a 60- to 80-gallons-per-minute sump pump in the riser where it will pump the water out and away from the home to a low point on the property (sloping away). You will need an electrical permit to run wiring to this corner of the basement to power the sump pump if no electrical outlet currently exists in that location. Locate the drain outlet in accordance with local regulations with regard to distance from septic tanks and your neighbor's yard. Also, the end of the pipe needs to be rodent-proof during the dry season.

Because a high concentration of water comes in during the wet season, it might be a good idea to install a couple of tees in the system for riser pipes with screw-on caps. These riser pipes could serve as inspection holes and clean-outs in case the system gets plugged.

Finally, remember that a pump depends on electricity to work. Consider adding a generator as a backup to keep the system running if your electrical power should go out during the wet season. Install rain gutters around the entire home with the downspouts going to long splash blocks draining away from the home. Make sure the ground slopes away from the home at least 1/4 inch per foot to help drain water from the home. Hire a waterproofing contractor (found in the Yellow Pages) to clean any cracks in the foundation and fill them with epoxy.

Unfortunately, after all this work, there's still no guarantee that the system will keep the basement dry; you are up against Mother Nature and it's possible the house is located in a high-concentration water area.

I believe the French drain system will allow you to finish your basement, and I commend you on your efforts to rectify the problem on your own. However, professionally speaking, I agree with you that hiring a specialty contractor would be worth the money.

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C.R.S., Inc. · Spokane, Washington · USA