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o \Vildlands - Communities with very low-density development and much morc open space already have functioning natural systems. Local officials in these areas have the opportunity to safeguard floodplain functions at the outset, and to maintain valu~ able habitats and superior \vater quality. It may seem burdensome to plan for the protection of natural resource functions, particu- larly in heavily developed areas where economic concerns and space limitations are pressing issues. But every community must recognize that decisions about floodplain resources are decisions about the community's future. With careful consideration and planning, rivers and streams can be aesthetic and functional assets that reflect commu- nity pride and ingenuity. However, a community that ignores the importance of natural floodplain functions may ultimately face nood losses and deteriorating water quality. In the end it would be less costly to plan "veIl now. Of course. not all human activities are incompatible \vith healthy, functioning floodplain ecosystems. Land uses that allow native vegetation to flourish and do not disturb soils are highly suitable within the floodplain. Well-placed parks or recreational areas that include vegetation are often ideal for maintaining flood storage capacity, and help to support the floodplain functions that protect water quality and sustain habitats for di- verse "vildlife species. Even open space areas such as agricultural lands can help to maintain flood storage capacity. In addition. there are proactive measures to restore natu- rally functioning floodplains, such as protecting or planting vegetated buffer strips and creating channel alterations for fish habitat improvement. The following sections de- scribe specific land uses and their relationship to floodplain functions: Urban and Urban Fringe Areas - Development within floodplains often occurs without consideration of the effects on floodplain natural resource functions. If an area is built up during a period when there have been few !loads, the need for the flood storage capacity of a naturally functioning floodplain may have been overlooked. The loss of natural !loodplain functions in heavily developed areas not only impedes flood storage, but also increases erosion and reduces the mitigating effects that vegetated areas can have on the pollution of waterways. Impermeable surfaces such as buildings and pavement replace vegetation as ground cover. increasing the runoff that would have infiltrated in a natural floodplain. The removal of vegetation. destruction of wetlands, and paving in urban and suburban settings can thus increase the risk of flooding. Upstream development outside the floodplain can also result in increased runoff. Vegetation loss and excessive runoff within the floodplain can also cause increased erosion and sedimentation. which may cover spawning areas and bury food sources in streams. Loss of vegetation also removes sources of shelter and food for wildlife, and human-made structures may present barriers to migration and reproductive activity. The lack of naturally functioning floodplain resources in urbanized or developing areas also has significance for water quality. Diffuse "nonpoint sources" sources of pollution related to urbanization, such as lawn fertilizers, leached materials from waste disposal areas, and chemicals leaked from automobiles, present a threat to \vater quality. Al- though it is most effective to address such problems at their source, vegetative buffers along waterways can help to mitigate such pollution. Urban areas also present direct "point sources" of pollution to waterways, such as sewage treatment plants and indus- trial discharge. Riparian vegetation would have little etlect on this type of pollution. \Vetlands are particularly vulnerable to loss through human intervention. The draining and filling of wetlands for development and agriculture results in the loss of an impor- tant natural system for reducing runoff and maintaining the quality of surface and ground- 1111 Figure J J - Floodplain development in the United States, as well as other countries, has significantly increased flood damages and oftCJI degrades the floodplain en~'ironmeflt.