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Ke to Justifications for Amendments to Title 24 of the California Code of Re ulations: C. This amendment is justified on the basis of a local climatic condition. Local climatic conditions include a low amount of average yearly rainfall, which tend to be concentrated from October through April. From May through September, a dry period occurs where daily temperatures remain high, and there is little measurable precipitation. In addition, the local climate frequently includes high winds which sweep down through the valley. These seasonal climatic conditions during the late summer and fall period create severe fire hazards to the public health and welfare in the City. The California Division of Forestry &Fire Protection has classified areas within and adjacent to the City as Very High Fire Severity Zones. The aforementioned conditions combined with the geological characteristics of the hills within the City create hazardous conditions for which departure from the California Building Standards is re uired. G. This amendment is justified on the basis of a local geologic condition. The City is subject to earthquake hazards caused a number of earthquake faults that are located either within or in close proximity to the City. Those with the most direct and potentially destructive impact are the San Andreas, Calaveras, Hayward, Greenville and Concord -Green Valley Faults. The U.S. Geological Survey (USGS) has identified a 72% probability of at least one earthquake of magnitude 6.7 or greater occurring in the region before 2043. Recent earthquake damage studies, including the 1994 Northridge earthquake, have indicated the lack of adequate design and detailing as a contributing factor to damages that reduced the protection of the life -safety of building occupants. Because the City is within a seismic area which includes earthquake faults within and through the jurisdictional limits of the City, the modifications and changes cited herein are designed to better limit property damage as a result of seismic activity and to establish criteria for re air of dams ed ropert followin a local emer enc . T. This amendment is justified on the basis of a local topographic condition. Local topographical conditions include hills on the western border and flat area on the eastern border. The narrow and winding access along with steeply sloped streets in the hills makes timely response by fire suppression vehicles difficult. Interstate 680 divides the City into two sections, and circulation between areas of the City rely on both freeway overpasses and underpasses. In addition, local traffic must also pass over railroad tracks, creeks, and bridges (to cross arroyos). Water lines which come from tanks on the hills of the City must also cross the interstate to feed the automatic fire sprinkler systems installed in buildings throughout the City. During peak a.m. and p.m. traffic periods, the City experiences heavy traffic congestion at key intersections, and near many freeway on-ramp and off -ramps. In the event of an accident or emergency at one of these key intersections, bridges, or other circulation corridors, sections of the City could become isolated and response times increased beyond ideal levels. Combined with both the climatic and geologic hazards, these topographical conditions require modifications from the State Building Standards to miti ate these conditions. Page 6 of 52