No Adverse Impact: New Direction in Floodplain Management Policy

Abstract

Abstract:Annual flood losses in the United States continue to worsen in spite of 75 years of federal flood control and 30 years of the National Flood Insurance Program. This trend is unnecessary, and is primarily due to federal policies that have encouraged at-risk development, provided for insufficient consideration of the impact of that development on other properties and on future flood and erosion potentials, justified flood control projects based on a benefit-to-cost ratio that favors an intensification of land uses within the floodplain, and engendered an unhealthy reliance on federal resources by state and local governments. The authors propose a new "no adverse impact floodplain" approach that shifts the focus from the techniques and standards used for floodprone development to how adverse impact resulting from those land use changes can be planned for and mitigated. The proposed policy promotes fairness, responsibility, community involvement and planning, sustainable development, and local land use management, while not infringing on private property rights. 2 INTRODUCTIONFlood losses in the United States continue to escalate. This increase in the level of damage to public and private property, amounts spent on disaster relief, disruption in lives and businesses, and loss of habitat and other water-related resources has occurred in spite of nearly a century of flood control, the implementation of floodplain management standards in about 19,000 communities nationwide, and the mapping of hundreds of thousands of miles of floodplains. Average annual flood losses in the United States are currently estimated at $6 billion. This is a four-fold increase over the past century, or a doubling in terms of dollars of damage per capita in the United States. The general trend is for flood losses to increase every decade.It is fairly obvious that the policies of governments at all levels, combined with market forces, are leading to more intense uses of floodprone lands throughout the country. Perhaps less obvious is the potential damage brought about when a floodplain is developed or filled so that floodwaters are pushed onto other property, or when the watershed outside the floodplain is developed and the newly increased runoff is allowed to flow freely downhill.Contrasting these land use realities with economics, the argument can be made that the nation as a whole is better off as a result of these investments in floodprone development-that flood losses are simply the price the nation pays for growth. Economic arguments such as this have become a key factor in establishing a federal government interest in flood control. Others have compared flood losses to the gross national product and found no adverse trend. Unfortunately, an alternatives analysis has never been performed to determine if the same level of expenditure and investment outside the floodplain would have led to a better return.The reality is that when floods hit, people are forced from their homes and businesses, and many never recover financially from ...

Identifying factors influencing flood mitigation at the local level in Texas and Florida: the role of organizational capacity

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One Step Forward, Two Steps Back on U.S. Floodplains

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Climate Change and Floodplain Management in the United States

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