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Figure 3.2. Using NFIP Standards in local Ordinances Communities participating in NFIP must decide \vl1(~thcr to place 0JFIl' standards in a floodplain management ordinance (with appropriate references to the standards in the zoning and subdivision ordinance) or incorporate the standards directly into zoning and subdivision ordinances. 8e10\\' are subdivision provisions from the Floodplain Management chapter of the .\1arin County, California, code (Chapter 23.09) that satisfy NFIP minimum subdivision requirements. (A) All preliminary subdivision proposals shall identify the tlood hazard area and the elevation of the base flood. (B) All final subdivision plans ...."'ill provide the elevation of proposed structures and pads. If the site is filled above the base tlood, the final pad elevation shall be certified by a registered civil engineer or licensed land surveyor and provided to the floodplain administrator. (C) All subdivision proposals shall be consistent \vith the need to minimize flood damage. (D) All subdivision proposals shall have all utilities and facilities under the control of the county located and constructed to minimize flood damage. (E) All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage. the regulation of street layout; the installation of utilities; lot size, shape, and setbacks; curbs, sidewalks, and gutters; open space; and public improvements. Most states also give local governing bodies the pm-ver to require other types of improvements or protections for certain lands \vithin subdivisions. These may include soil erosion controls, aesthetic controls, preservation of farmland, and flood control measures. Subdivision ordinances that are drafted \""ith the purpose of reducing or minimizing flooding susceptibility usually require each lot to have a buildable area on natural high ground. These ordinances also set construction and location standards for the infrastructure built by the developer, including roads, sidewalks, utility lines, storm se\vers, storm\vater retention and detention basins, and drainageways (ASFPM 1996, 15). Common lv, a subdivision ordinance will include abridged descriptions of NFlP minimum standards for subdivisions. (See Figure 3-2.) Subdivision regulations, particularly those adopted in the last decade, also contain provisions for drainage, storm\,vater management, and erosion and 18 sedimentation control. As with floodplain provisions, these regulations are either adopted separately or included in the subdivision ordinance. OTHER LAND-USE PLANNING TOOLS Comprehensive planning, zoning, and subdivision control are the bread and butter of land-use planning. But there are a wide range of additional land planning and conservation techniques that can achieve the objectives of preventing and reducing damages to subdivisions in or near floodplains. The techniques described belm'v would be part of a local government frame'\:vork that encourages better design of subdivisions in flood hazard areas. These tools can be seen as policy fundamentals-the local government incorporates these concepts into plans and ordinances to show that it is open to alternative and innovative development patterns that \vill protect floodplains. In addition to the floodplain management planning activities described above, local governments that participate in CRS are eligible to receive CRS credits for some of the activities described below. Property o\""ners who hold NFlP flood insurance are eligible for premium reductions if their community undertakes certain activities under CRS. Cluster Development (Open Space Subdivision Design) Cluster development (more recently called open space subdivision design or open space zoning) is most often associated with the preservation of farmland and woodlands and the protection of rural character. Many planners use the terms cluster development and open space zoning interchangeably, but, according to some, open space zoning is used to esta blish greater requirements on the size and quality of the open space protected (Arendt 1991; NAHB 1991). Cluster development is also a commonly tou ted method for reducing the cost of housing by reducing the public investment needed for land clearance, site preparation, and infrastructure. This type of development allows the same gross density or overall amount of development that is already permitted in the zoning ordinance, but construction is typically limited to one-half of the parcel. The remaining open space is reserved for common use. That open space is permanently protected under a conservation easement and is usually maintained by a homeowners association. Conventional zoning inadvertently but directly discourages cluster development. Traditional zoning emphasizes separating incompatible uses and establishing development standards like maximum densities and minimum setbacks. Traditional zoning has resulted in subdivisions with houses, streets, and yards, but very little open space. In order for developers to depart from the norm, the regulatory means to do so must be available, and the developer's options must be made clear. Certain provisions in subdivision regulations, such as limits on impervious surfaces, requirements that set minimum buildable area for each lot, as \vell as drainage control regulations that prohibit an increase of runoff from a site after it is developed, all work in