In many cases, more damage can be caused by pumping too quickly. As the basement fills with water, it acts as a brace to water pressing against the outside walls. Pump it out too fast and the walls could buckle and cave in. Pump in stages, about one-third of the water each day and watch the walls to make sure they aren't caving in from the outside pressure. A long-range solution is to install a sump pump.
Roof leaks Just where the roof is leaking is often the least revealing facet of a water-logged home.
Water or moisture on a sloping roof won't leak down in a straight line, but drips along the rafters to some point away from the actual leak. Begin your search by looking for discolored ceilings or walls. To find the source, go into the attic with a flashlight. The source may be noticeable during a rain, but not so obvious afterward. If it isn't raining, someone may have to spray the roof with a garden hose while you are inspecting in the attic.