You can avoid or solve most basement seepage problems by following these simple corrective steps, which are listed in order of priority.

1. Keep gutters and downspouts clean, and direct them away from the basement. Downspouts must be routed to a storm sewer or at least 6 feet away from the foundation to an area where the water flows away naturally.

2. Grade soft surfaces. All surface water must flow away from foundation walls. Soil should pitch away from the basement, dropping 6 inches for every 6 feet. The soil under any bark or stone mulch around your home must pitch away; ideally, any plastic under the mulch will pitch away too. Check under decks and porches. During a heavy rain, walk around your home to check for pooling water. No water should pool around or flow toward your basement walls.

3. Grade hard surfaces. All concrete and asphalt surfaces must pitch away from the basement. Watch for slab concrete beneath decks. Check all stoops, drives, and walks.

4. Grade the soil around window wells to direct water away. Seal the window well tightly to the foundation, and keep the inside of the well clean. The inside of the windowshould have a base of 6" gravel-not mud. Also, the window well should either have its own drain or should into the exterior drain tile system through the gravel base.

5. Check the palmer valve. This check valve must swing of improper materials easily broken by frost. Also, many open easily to drain water from the drain tile system. If it is stuck closed, water may back up in your basement, and eventually the drain tiles will become plugged with debris. Use a wire to hook the bottom of this round flap valve; it should swing upward on a hinge at the top of the disc. If the valve is stuck, free it with penetrating oil and a pry bar.

6. Check the sump pump. The float must easily move up and down to activate the pump. If the float sticks, you will have a flood. Make sure that the pump is secure and will not allow the float to stick to the sides of the crock or the cover. Lift the float to check that the pump will remove water from the crock; the pump should switch on when the float is 8 to 12 inches from the top of the crock. If the pump allows higher water levels than this, seepage near the floor may occur. Replace a sump pump that is old and worn. If your pump runs often, have a spare sump pump handy.

7. Look for gaps and cracks in joints. These can allow water to seep next to the basement. The gaps can be filled with a backer rod and concrete joint filler.

8. Check for cracks in poured concrete walls or block walls. These should be evaluated and patched by a professional.

9. Check for problems with underground storm drain lines. If damp spots and seepage appear near a sump pump or downspout storm sewer line, the problem may be a broken or plugged underground line. You can test this line by running water into the pipe with a hose and watching for seepage in the basement. You can also temporarily abandon the undergound line and route the sump pump or downspout to the surface, well away from your home. If seepage no longer appears in the basement, you'll know the problem is a broken drain line.

10. Investigate underground water supply lines. If seepage occurs near the water main into your home, suspect a broken underground water line.

11. Investigate all homeowner-installed underground drain lines. Often they are unable to withstand freezing because they are installed too near the surface and/or they're made of improper materials easily broken by frost. Also, many such lines can't effectively carry water away from the foundation because they have poor pitch or are undersized. Temporarily abandon these lines to test them. If you see water bubbling up from connections to these lines, you have a problem.

12. Watch for roots in the sump pump crock. Roots inside the crock mean there are roots in the bleeders and in the outside drain tiles. An expert should evaluate this problem.

During a rainstorm, gutters route runoff from a very large surface-a home's roof-to where it can drain away from the house. By doing so, they protect siding, windows, doors, and foundations from water damage and help prevent flooding in basements.

To do their job, gutters and downspouts must be clear of leaves and debris. If they aren't, drain outlets will dam up and rainwater will fill the gutters, back up, overflow, and eventually pull gutters loose from their mountings. Water that pools in troughs will rot wood gutters and rust sheet metal ones.

You can hire a service to clean your gutters, but by doing the work yourself you can save $100 or more.

Plan to clean gutters at least twice a year-more often if the roof is directly beneath trees. But only take on this task yourself if you know you can work safely from a ladder or the roof. If your roof is higher than a single story or you're unsure of your job's safety, you're better off hiring a professional.

Scoop out loose debris.
Starting at a drain outlet at the low end of a gutter, use a narrow garden trowel to scoop out loose debris, working away from the drain outlet. It's usually easiest to do this when the debris is slightly damp and pliable, not soggy or dried and encrusted. To minimize cleanup later, you can scoop the debris into a plastic garbage can liner.

Blast out the gutters with a hose.
Using an on/off high-pressure nozzle mounted at the end of a water hose, wash out each length of gutter, working toward the drain outlet. This can be a messy job-avoid splattering mud all over your house. If necessary, use a stiff scrub brush to break loose encrusted dirt.

Clear obstructions in drainpipes.
If water doesn't drain freely through drainpipes, try flushing debris down them with the hose. If that doesn't work, use a plumber's auger (snake) to free and pull out debris from the bottom as shown. You can help keep the drainpipes free of debris by installing leaf strainers in at the tops (these are available at home improvement centers and hardware stores).

Repair leaks.
If you see areas where water is leaking through seams between gutter sections, mark the leak locations with chalk, allow the gutter to dry completely, then seal the leaks from inside with gutter seal.

Re-align sagging gutters.
If gutters are not sloped properly at a pitch of 1 inch for each 20 feet of length, they won't drain properly toward downspouts. To support sagging gutters, bend or add new hangers, or add new fasteners.