Agenda - Council - 03/12/1984 - Laserfiche WebLink

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held a public official personally liable for pro- viding inaccurate flood data or for implementing floodplain regulations or flood control measures. 7. Q. What is a "regulatory floodplain"? A "reg- ulatory wetland"? A. A "regulatory floodplain" is frequently defined by state or local regulations to include all land within reach of a "one-hundred year" flood, i.e., a flood with a probability of occurring in any given year of one percent. This standard has also been adopted by the National Flood Insurance Program which refers to this level of flooding as the "base flood." Executive Order 11988 issued by President Carter in 1977 imposes a higher degree of restric- tion in the case of "critical facilities," such as~:hos- pitals or public utilities, where federal subsidy or licensing is involved. Such facilities, whose inun- dation would be publicly disastrous, are required to be located outside the "five-hundred year flood- plain" (having a 0.2-percent chance of flooding in a given year). If detailed maps of the one- hundred year or five-hundred year floodplains are not available, states and communities should at least manage and regulate those areas which have been flooded in the past or which the community has reason to expect to be flood prone, based upon the best available data and local knowledge. A "regulatory wetland" is defined by the U.S. Army Corps of Engineers under regulations adopted to implement Section 404 of the Federal Water Pollution Control Act Amendments of 1972 and the Clean Water Act of 1977 to include: "... those areas that are included or sat- urated by surface or ground water at a fre- quency or duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated conditions. Wet- lands generally include swamps, marshes, bogs, and similar areas." Similar definitions are frequently expressed in state and local regulations, which also may list indicator wetland plant species. 8. Q. What are the basic regulatory techniques available to communities for managing and regulating their floodplains and wetlands? A. Local and state programs utilize five types of legal measures: Floodplain and wetland zoning specifies the location, usage, and density of new structures in regulated areas. Structures in exist- ence when a zoning measure is adopted are nor- mally protected as legal "non-conforming uses." Such structures may continue to be occupied and used for the same purpose, but they may not be expanded or changed to a new purpose. Special exceptions may be granted. for structures related to agriculture, to water-dependent activities such as marinas, or to other facilities which must be located in regulated areas. Building ;;odes regulate the design, elevation, and construction materials of new structures. Generally, new structures must be elevated or floodproofed to the one-hundred year flood level. Building codes are generally administered on a state-wide basis. ., Subdivision regulations control'the process of subdividing a large parcel of land into smaller lots for resale. As a condition to approving a proposed subdivision, a local community may require the developer to refrain from building in regulated areas and to install suitable drainage facilities. The subdivider may also be required to dedicate wet- lands and floodplains for use as subdivision recre- ation areas. Sanitary and well codes establish minimum standards for on-site waste disposal and water supply systems. They may prohibit such facilities in areas of high ground water and flood hazards. Special watercourse, wetland, or floodplain encroachment statutes or ordinances are some- times adopted by states or local governments to control wetlands and floodplains. Within these areas, any proposed structure, fill, dredging or other alteration must receive a permit from the appropriate public authority. Q. Do state enabling acts for zoning and subdi- vision control authorize adoption of flood- plain and wetland regulations? A. Local general purpose goverranents in all states possess sufficient power to adopt floodplain and wetland regulations. At least thirty-three states specifically authorize floodplain zoning and thirty- two authorize subdivision control related to flood- lng. In other states, general enabling acts authorize regulations for protection of the "public health, safety, and welfare." These have been held broad enough to authorize flood regulations. No local floodplain or wetland regulation has been held to be invalid due to lack of enabling authority. Power to regulate these areas may also be derived from local home rule statutes, charters, or constitutional provisions.