Use smart growth and watershed planning as key features in flood prevention and management programs


Although flooding is often referred to as a natural disaster, states, local officials, and water resource organizations are increasingly recognizing that some flooding is the result of man-made actions arising from poor land use planning and resource management decisions.

The relationship between poor land development patterns and flooding is largely the result of increased amounts of impervious surface coverage and the loss of water storage areas. As forests and fields are converted to development or other uses, rainwater that previously soaked into soils instead runs with increased velocity over hardened surfaces. Models show that the more extensive and connected the new development, the higher the risk of flooding. While most flood codes are directed at regulating individual building sites, prevention can be enhanced by steering redevelopment to less flood-prone areas, strengthening low-lying cities, and minimizing loss of forest cover, wetlands, and open space.

There are several ways states can improve flood prevention and mitigation policies. First, the American Association of Floodplain Managers advocates the adoption of a "No Adverse Impact" floodplain management framework. "No Adverse Impact" floodplain management rests on the concept that the actions of a property owner should not be allowed to adversely affect the rights of other property owners. While applied routinely at the individual site level, this concept is increasingly being considered for a larger community scale to address downstream impacts caused by decisions made elsewhere in the watershed. "No Adverse Impact" is not a "no development" stance, but rather a sharper focus on the ramifications of various development scenarios and assignment of mitigation. Floodplain managers speak of this as "protecting property rights on both sides of the fence." Projected impacts are matched with mitigation early in the planning stage. This larger planning framework also allows planners to anticipate changes likely to come as a result of climate change.

States also have a role in bridging the Federal Flood Insurance program and the Community Rating System, which establishes lower flood insurance rates for communities based on implementation of flood mitigation measures, such as revised zoning and building codes. FEMA also supplies planning funds through the Flood Mitigation Fund, which are targeted at lowering risks through comprehensive planning.


A comprehensive State Flood Management program consists of measures addressing both prevention and mitigation. States will likely retain traditional emergency response and natural resource management responsibilities, but as issues related to build-out, liability, and climate change increase, states are in a unique role to broker solutions. These solutions will require sophisticated modeling and quantification, and as such, are best executed in conjunction with a green infrastructure or other mapping/modeling effort. Other avenues include the state’s stormwater management programs, where low- or no-impact policies for new development are key.

Second, states can integrate ongoing smart growth efforts into the Community Rating System. FEMA assigns points for various activities related to smart growth, such as comprehensive planning. Where older cities with existing infrastructure also lie in flood and hazard zones, states will increasingly be called upon to work with communities on risk reduction, which will include acquisition of open space and infrastructure upgrades.


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