Many things can be done before the snow melts or before a heavy rainstorm to reduce water damage to home and property.
Check your sump pump.
Clean the sump pump and pit and test the pump by pouring water into the pit. Consider having a spare submersible portable sump pump. Make sure the discharge hose delivers the water several feet away from the house to a well drained area that slopes away from the house. If the hose outlet is too close to the house foundation or on flat ground, the water may simply recycle down through the house drain tile causing more water damage.
Save valuables from water damage at higher ground.
Move items such as irreplaceable family photo albums, high school yearbooks, personal videotapes, tax records, insurance policies, and household inventories off the bottom shelves in the lower level of your home to prevent water damage.
Move hazardous materials to higher locations.
This includes paint, oil, cleaning supplies, and other dangerous materials.
Plug basement floor drains with removable grids.
If sewer backups may occur, install drain plugs available from hardware stores. One type of plug has a rubber center that expands to fill the pipe when the top and bottom metal plates are squeezed. If a commercial plug is not available, a flexible rubber ball about 1¼ times the inside diameter of the pipe can be wedged into the drain to create a tight seal. Brace the ball securely in the drain with a 2X4 against the ceiling. Hold a board or piece of plywood on the ceiling and slide the 2X4 against the bottom of the board to avoid damage to plaster ceilings. For a suspended tile ceiling, remove ceiling tiles to get access to the ceiling joists. Span a 2X4 across the two joists and wedge the vertical 2X4 between it and the ball.
Plug drains to prevent water damage.
Unbolt toilets from the floor and plug the outlet pipe using the same procedure as for floor drains. Shower drains can be plugged this way too. Most washing machines and basement sinks have their drain connections about 3 feet above the floor so they won’t not overflow if the water doesn’t get that high. If necessary, these drains can be disconnected and capped or plugged with braced rubber balls to prevent water damage.
Move snow away from the house’s foundation.
If the ground is sloped 1 inch per foot near the house, moving snow just 3 to 5 feet from the house will reduce problems.
Keep water out of window wells.
Since windows can’t withstand much pressure, build dams and contour the ground so water will naturally drain away from the house.
Get downspouts draining away from house.
This is a common oversight causing water damage. Make sure downspout extensions are in the down position or use flexible tubing so that as snow melts they can carry the water away from the house.
Prepare appliances for flooding.
Shut off appliances at the fuse box or breaker panel. Put freezers, washer, dryers, and other appliances up on wood or cement blocks to keep the motors above the water level. If high water is imminent and large appliances can’t be moved, wrap them in polyethylene film, tying the film in place with cord or rope. The water will still get in, but most of the silt won’t so cleanup will be easier.
Shut off electricity to areas of the home that might flood.
Even if flood waters are not reaching electrical outlets, the risk of electrical shock to someone working in a flooded basement is high with electric motors in the furnace, freezer, washer, dryer, and other appliances. Shut off electrical breakers or unscrew fuses. Don’t stand in water and turn off electrical switches. If this must be done, use a dry piece of wood or a plastic or rubber pole to do the switching, and stand on a block of wood or a plastic crate that doesn’t conduct electricity. If floodwaters are getting close to the electrical entrance box, call the power supplier and have the electrical supply to the house disconnected. If the floor is damp but not really flooded, ground fault circuit interrupters reduce the risk of using electricity. In newer homes, interrupters can be identified by the buttons between the top and bottom outlets. They can be added to any outlet or in an extension cord to turn off the power if there’s danger of water.
You may also want to refer to Water Damage Repair.