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After the deluge, how to flood-proof your drowned cellar

It happens every spring, or nearly every spring.

A heavy snow cover starts to melt, but the ground remains frozen. Then comes a deluge, several inches of rain.

And, alas, in the cruelest month of March, floods: flooded basements, flooded yards, and flooded streets.

Then panic sets in, with a quick buy-out of sump pumps, floor pumps, and all the tubing and pipes that go with pumps and sumps. Stores were stripped by 10 a.m. Thursday, and anyone who procrastinated was out of luck.

First thing to do in that case is to call the fire department and beg them to pump out your cellar. Get in line, because the departments are busy, and you will have to wait your turn.

But what, in the first place, is happening? Why are so many basements flooding, even some that have been dry for decades?

It's a combination of natural occurences. After a winter of heavy snow, the snow melts, but the ground is still frozen. Then comes a heavy rainfall like last Thursday's all-day deluge, and the water, which normally would soak the ground, cannot do that because of the frozen ground, so it goes right down the foundation of your house, and through the fieldstone, or if the foundation is poured concrete, under it, coming up on the floor between foundation and floor.

Water that does not go down the foundation goes elsewhere to flood yards and streets.

The melting snow adds to the water flow, but the flooding sometimes can occur without a snow cover. The frozen ground creates a gap between ground and foundation, and that is where the water goes.

The first priority is to pump out the cellar. And since the rain has stopped, chances are that the water will stay out once it is pumped out.

Then, let the cellar dry out, and dry out any contents as well. If the water got high enough to affect heating burners or water heaters, let them dry out, too. The only way to determine if they are damaged is to turn them on, carefully. The same goes for washers and dryers. Many appliances, including those with electric motors, can survive a temporary flooding without damage.

A word of caution when working in a flooded, wet or damp cellar: Steer clear of electrical appliances and the fuse box or breaker panel. If you have to deal with them, call an electrician.

To dry out a cellar, open windows and doors for good cross-ventilation. Put a fan on the floor to hasten the drying.

Once the cellar is dry, you can check for mold. Ordinary flood water is usually not a health hazard, as sewage is, but disinfecting might be a good idea.

To handle the mold and bacteria, wash surfaces and other items with a solution of one part household bleach and three parts water.

In the future, avoid storing water-sensitive items in the cellar. And whatever you do store in the cellar, put it on a wood platform or raise it several inches above the floor.

Now down to the nitty gritty: How can one prevent future flooding?

Install a sump in the basement floor, which is a hole about 24 inches in diameter and 24 inches deep. You can buy sump liners in home-supply stores (maybe they are already sold out) that fit in the opening cut in the floor.

Such a sump, and there can be more than one, can fill with water before the incoming water floods the floor. An automatic pump then pumps it away. The water must be pumped at least 10 feet from the house; if is isn't, it will come right back in.

A cellar with a sump and pump has a good chance of staying dry, even during severe water invasion. A friend called the other day and admitted that he did not have his pump plugged in, so he had a big problem.

Sometimes there has to be a more drastic fix, in addition to the sump and pump. And that is a French drain, a perforated pipe installed under the cellar slab inside the foundation, all the way around, leading to the sump.

French drains will intercept ground water coming in the floor between foundation and floor, and also water coming down the outside of the foundation.

They are best installed by professionals. To find such a professional, check the Yellow Pages under "Basement Waterproofing." One good thing about a professional installation is that they are usually guaranteed for life.

Another way to try to fend off flood water is to regrade the land outside the foundation, so that it slopes down from the foundation, allowing water to drain away. This is not always possible, because there should be at least eight inches of foundation showing between ground and siding. But if it is possible, it will go a long way in keeping the water away.

Another trick: Build a concrete apron around the perimeter of the house, a slab 18 inches wide and six inches deep, slightly sloped for runoff.

This might help, too, but the handyman has such an apron, and the ground has a distinct down-slope all the way around the house.

And guess what. He had two inches of water in the cellar.

The moral of that story is: Nothing is certain, nothing is guaranteed. Unless it's a slab on grade with no basement.


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