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13 Results and Conclusions The three examples are for illustrative purposes and represent only basic procedures for identifying, analyzing, and classifying alluvial fans. They also cover the basic procedures for compilation and interpretation of geologic, topographic, soil, and aerial maps for analyzing alluvial fans, Fieldwork procedures/guidelines were discussed throughout the examples but the actual fieldwork has not been performed. Although the examples have not included fieldwork, the results validated and demonstrated the usefulness of the established procedure for investigating and classifying alluvial fans. The limits of flooding and boundaries and the overall accuracy of these examples should be weighted against the effort put into the analyses. It is highly recommended that fieldwork, which includes geomorphologic observation and measurements of channel dimensions and patterns, be performed for a site-specific investigation. RECOMMENDATIONS Alluvial fans in California are desirable locations for residential and commercial development because they are often scenic areas with good foundation material. The soil types easily facilitate the installation of water and sewer systems. Their development has progressed with rapid urbanization in recent decades, and pressure for their development continues to increase. Existing development as well as any future development on alluvial fans must be planned, managed, and regulated. To meet this objective, the following actions are recommended: . Alluvial fans in California should be identified, evaluated, and classified using the three- step procedure in the base classification system. . Evaluations of alluvial fans should be site-specific for a more accurate and reliable prediction of the flood hazards, Onsite evaluation of the flood hazards requires individuals who are knowledgeable and experienced in the scientific study of alluvial fan characteristics and processes. · Minimum basic guidelines for flood plain management on alluvial fans should include identifying the alluvial fans (Step 1), determining the active and inactive status of the alluvial fan or parts of a fan (Step 2), and defining inactive fan flooding, assessing active fan flooding, and determining active fan development (Step 3). · Delineating and mapping standards for alluvial fans and their boundaries should be established. This should include designating flood hazard zones based on the 1 DO-year event. Criteria for mapping standards include topographic features; contour interval; base scale map; roads, buildings and landmarks; hydrologic features such as rivers and levees; and, geographic orientation and notations. . Structural measures to protect existing development on alluvial fans should be site- and application-specific, Nonstructural measures should also be considered, including relocating existing structures, raising structures, and/or avoiding development on areas at risk.