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Loss of Life: Loss of life is considered unlikely under the 100-year flood condition, <br /> because the depth of inundation is seldom more than 5 feet and the rise of water level <br /> would be gradual enough for almost anyone to reach safety during a flood. Drainage <br /> ways are always potential hazards, and possible loss of life may in fact occur, but for <br /> purposes of this analysis,no loss of life was considered. <br /> Direct Damages: Direct damages comprise the largest damage category and they can be <br /> expressed in monetary values with a fair degree of accuracy. In urban areas, direct <br /> damages occur primarily to buildings and to public facilities such as bridges, roads, <br /> utilities, and related facilities. Rural areas direct damage relates primarily to loss of <br /> crops, loss of out-buildings, cleanup, and work required to return fields to usable <br /> condition. Flood damage to property is a function of the type of property, property value, <br /> replacement cost, velocity of flood flow, and the depth of floodwater. Depth of <br /> floodwater at each building, or groups of buildings was calculated for various frequency <br /> events. Calculated flood depths were increased by velocity head to account for the flood <br /> flow velocity effect. No records of the value of building contents are available, and the <br /> contents of buildings are therefore estimated to be either 30 percent of the value of the <br /> structure (residential) or 50 percent (commercial). Damages to bridges, culverts, and <br /> flumes were not assumed unless the flood water levels exceed the top of the waterway <br /> opening. Structures were assumed to be lost at a damage value equal to their present <br /> estimated replacement cost. Direct flood damage to water, sewer, gas, electrical and <br /> telephone lines was estimated from City maps. Erosion damage along the waterways and <br /> clean-up costs following a flood were estimated to be a function of waterway reach <br /> length. Erosion damage and clean-up costs were assigned only to improved channels, not <br /> to unimproved channel reaches. Crop damage was assumed to be the value of one <br /> season's production. Based on discussions with the Department of Agriculture, it was <br /> assumed that the average production value per acre for farmland in the Pawnee Creek <br /> drainage basin is $500/acre. Direct damage for the City of Sterling was taken from the <br /> Flood Plain Information and Drainage Plan prepared in May 1983 by Leaf and Resource <br /> Consultants. This report was the basis for the current FIRM mapping for the City. <br /> Damage figures were updated using inflation figures from the Colorado Department of <br /> Revenue. <br /> Indirect Damages: Indirect damages include the value of lost business and services; and <br /> the cost of alleviating hardships, safeguarding health, rerouting traffic, delays and related <br /> phenomena, and the loss of sales taxes. The monetary value of indirect damages cannot <br /> be estimated as well as those of direct damages because of the lack of sufficient damage <br /> data. These damages, excluding the loss of sales taxes, were estimated as a fraction of <br /> direct damages following estimates used by the US Corps of Engineers. Local and State <br /> sales taxes are lost in commercial areas as a result of business disruption caused by <br /> floods. Tax losses were taken to be 5 percent of the commercial direct lost. <br /> Secondary Damages: Secondary damages are those damages, which occur outside of the <br /> immediate flood zones due to reliance on some output produced by the damaged property <br /> or supplied by some hindered services. No monetary values were assigned to the <br /> secondary damage in this study since normally the secondary damages tend to be offset <br /> by secondary benefits. <br /> 35 <br />