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<br />"protected" areas, This scenario creates a unique potential for catastrophic losses in the event of <br />failure, design exceedance, or eventual removal or decommissioning of the structure. As a <br />consequence, once a flood control structure is built, society must forever bear escalating operation <br />and maintenance costs. In addition, since structures are only built to a certain level of protection (for <br />economic reasons), events exceeding those levels can occur and damage will be greater than it would <br />have been even without the structure, because in the meantime no complementary nonstructural <br />measures (regulations, setbacks, insurance) were applied. <br /> <br />. Planning for structural projects must be developed from a watershed- or basin-wide perspective <br />to help determine appropriate, complementary structural and nonstructural approaches, <br /> <br />. A concerted effort must be made to estimate the useful life of existing flood control structures <br />nationwide, and to make plans for a comprehensive program of maintenance, inspection, <br />replacement, and removal as warranted, <br /> <br />. New structural measures should be built to protect not just to the 1 % chance flood, but rather to <br />the 0,2% chance flood, to avoid losses from catastrophic failure. <br /> <br />. There is a need for a maintenance, inspection, and safety program-similar to the Federal <br />Emergency Management Agency's Dam Safety Program-to oversee flood control works in <br />total. <br /> <br />. Flood hazard maps should depict the failure zones of all dams, levees, and floodwalls. Not only <br />is this identification important for notification and warnings, but also development in these zones <br />should have added flood protection, and flood insurance should be mandatory. <br /> <br />Dam Safety <br /> <br />Many of America's dams have exceeded their intended lifespan, are in critical need of repair, and pose <br />a serious safety risk. In the 1998 Report Card for America's Infrastructure, the American Society <br />of Civil Engineers noted that "an alarming number of dams across the country are showing signs of <br />age and lack proper maintenance, Downstream development is increasing. Dam safety officials <br />estimate that thousands of dams are at risk of failing or are disasters waiting to happen." According <br />to the American Society of Civil Engineers, more than 200 dam failures have occurred in the past 10 <br />years. Approximately 9,200 regulated dams are categorized as high hazard, that is, their failure will <br />likely cause significant loss of life and property, Thirty-five percent of these dams have not been <br />inspected since 1990 or before, and estimates for the cost of rehabilitation reach $1 billion <br />nationwide, <br /> <br />Ownership of dams and other flood control works historically has been dedicated rather haphazardly <br />to local sponsors that mayor may not have had the interest or ability to maintain the facilities. Often, <br />easements were granted for access and inundation that in today's legal climate would be viewed as <br />highly informal and even unenforceable, The Dam Safety Program facilitated by the Federal <br />Emergency Management Agency has urged the voluntary adoption of minimal standards for the <br />inspection and maintenance of dams. <br /> <br />Association of State Floodplain Managers <br /> <br />-11- <br /> <br />National Flood Programs in Review 2000 <br />