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outlets. Light or movable items, such as lawn furniture and bicycles, can be relocated after a flood warning is issued. Cost: Minimal to $20.000. In one hour a property owner can accomplish some wet flood proofing by moving valuables out of the floodable area. Costs can range from $3,000 for relocating the furnace, water heater, etc., to as high as $20,000 to rebuild the floodable area with water-resistant materials and to relocate all utilities to a new addition. 2.5 Sewer Backup and Basement Protection A sewer backup occurs during heavy rains. Stormwater flows into combined or separate sanitary sewers. overloading the system's capacity to carry the water to the sewage treatment plant. The water backs up through house service lines into floor drains and then into basements. Many basements are protected from groundwater problems by drain tiles that direct groundwater into sumps. Sump pumps move the water from the sump out to the ground, away from the building. Very heavy rains can overload this system; power outages and maintenance problems may knock out a sump pump. Should this happen, the system designed to keep groundwater out can act as a conduit to bring water into a basement. In some communities, sewer backup and basement flooding are bigger problems than overbank or surface flooding. Often they occur at the same time, so many property owners are not sure how the water entered their homes. Barriers and dry flood proofing projects need to account for backflows through sewer lines, and seepage of groundwater under the protective barrier during surface flooding. There are some inexpensive and usually effective measures for sewer backup, such as plugs and standpipes for the basement floor drain. This report, however, covers the more expensive approaches, where the owner may need financial assistance. The two most common measures funded by the communities interviewed are overhead sewers and backup valves. Overhead Sewer: An overhead sewer restricts backed-up sewer water to the plumbing system. A sump is installed under the basement floor to intercept sewage flowing from basement fixtures and the basement floor drain. The sewage is pumped out by an ejector pump in the sump (see Figure 6 on the next page). Plumbing fixtures on the first floor are not affected. They continue to drain by gravity to the sewer service line. It is unlikely that sewers will back up above the level of the overhead sewer line. If water does go higher, a check valve in the pipe from the ejector pump keeps it in the pipes. Backed up sewage is contained in the sewer pipes so there is no worry about overflowing laundry tubs or basement toilets. An overhead sewer is also illustrated in Figure 14 on page 29. Cost: $2,000 to $5,000 for a plumbing contractor to reconstruct the pipes in the basement and install the ejector pump. -7-