Who (or what) will stop the rain?

Homeowners, up to here with their flooded basements, look for answers

By Peter Hotton
Globe Correspondent / April 1, 2010

E-mail this article

Invalid E-mail address
Invalid E-mail address

Sending your article

Your article has been sent.

  • E-mail|
  • Print|
  • Reprints|
  • |
Text size +

Help, my basement is flooded!

Help, how can I get rid of the water?

Help, how can I keep it away?

These plaintive, often panicky cries have been heard across the land as record rains fell in March, and did not let up for days, saturating the ground and raising the water table high enough to produce up to and more than 10 inches in cellars.

When will it all end? The Handyman can’t tell you that, but I can tell you what I know about wet basements.

Why is it flooding?
For most of the soggy masses, the flooding was (or, sadly, is) not from water gushing through windows and other foundation holes, but rather underground water rising under the floor slab and, under pressure, squirting through joints where slab meets foundation walls. When that happens, the house is virtually floating on an underground sea. Well, not exactly floating, but leaking like a sieve.

The biggest hazard of flooding is damage to heating systems, water heaters, and appliances. One cure, of course, is to put these items above the highest water level. The hardest hit are finished basements.

Clearly, not all basements have flooded. Those with working sump pumps are relatively dry. Those without a pump bought up every one that was available. Stores ran out quickly, but should now be restocked.

Many homeowners have been caught unawares because they’ve never had a wet basement. The Handyman is one of them, dry for 40 years until now.

What kind of pump do I need?
In some cases, fire departments may drain the cellars of the elderly.

Otherwise, you’ll need to buy and install a sump pump or a utility pump. A sump pump is one that sits in a sump (a hole in the floor), usually 24 inches in diameter and 12-18 inches deep. The pump has a float that will turn it on when rising water reaches it. It shuts off when the water is gone. You can also buy a sump pump with battery backup.

A utility pump can be put on the floor and plugged in when water is measurable. They do not shut off by themselves; they must be unplugged when the floor is dry. Left to run without water, they will burn out. Be extremely careful when plugging or unplugging anything in a flooded area!

Utility pumps run from $50 and up, sump pumps $100 and up. Getting a sump pump installed can run from $500 and up. Stores also sell sump buckets, convenient containers to put in a sump that will keep silt out of the pump.

Can I keep the water from coming back?
A permanent solution to this kind of flooding requires professional help. Incidentally, trying to seal that joint between floor and foundation with hydraulic cement or any other sealer is doomed for failure. Water cannot be kept out. It can only be controlled.

There are two different kinds of flooding: One is rising water from the floor slab and through the joints between floor and foundation floor. The other is through cracks in the foundation. The cure is different for each.

For underground seepage, professionals install a French drain, a pipe around the inner perimeter of the foundation, just below the slab, leading to the sump and pump. This work is expensive, probably more than $10,000. But sometimes the installer will warranty “no flooding’’ if the pump keeps working.

The other professional fix is for water coming through wall cracks. An epoxy sealer is injected into the cracks from the inside. Trying to do this with hydraulic cement is unlikely to work. Doing it from the outside can work, but it is tedious and hard for the homeowner to dig down to the footings outside.

Check the Yellow Pages under “Basement Waterproofing’’ for professional help. Angie’s List is also a great resource.

What happens when the water is gone?
Ventilation will dry out the basement in days, sometimes weeks. Open windows for cross ventilation. Add an exhaust fan in one window. A dehumidifier can also work, but is expensive to run.

The faster a basement dries out, the less likely mold will grow. If you get mold, treat it with a mix of 1 part household bleach and 3 parts water. Or use Moldex, which is less caustic and claims to keep mold away longer. In severe cases, contact a mold remediation professional.

Sometimes flooded electric motors can be dried out and will work. All you can do is try. Replacement may be needed.

Flooded freezers, refrigerators, and other food containers cannot be cleaned. They must be discarded.

A flooded finished basement is an even tougher problem, obviously. Jettison rugs and other cloth materials that are beyond help. Cut walls a few inches above the high water marks and remove plasterboard or any other finishes. Remove any insulation and let the cavity dry out before putting in new insulation. Put on a new covering such as a water-resistant Blueboard or Greenboard. Or, exterior grade plywood, which will be easier to take off if the floods come again.

That is, when the floods come again.