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5 based on historical information may occur more often under changing climate conditions. 3 These changing conditions would translate to a shift in the FEMA maps of the 100- and 500-year floodplains, and have considerable economic consequences for the city in the event of a flood. Flooding already poses significant financial challenges to cities by incurring structural repair, transportation delay and utility service interruption costs.4 San Leandro will potentially face more frequent, severe floods Flood Insurance Rate Maps created by FEMA5 were analyzed to identify exposed assets in the 100-year and 500-year floodplains. The 100-year floodplain includes land that has a one percent chance of flooding in a given year and therefore is expected to flood once every 100 years. The 500-year floodplain includes land that has a 0.2 percent chance of flooding in a given year. The flood maps are based on historical data and updated about every 10 years. Although they do not currently incorporate climate projections into the floodplain delineations, they provide an indication of where floodwaters are likely to concentrate, even if the probability of flooding changes with the climate. Many citywide assets are exposed to flood risks According to 2009 FEMA flood maps, San Leandro has many assets located in areas that have a one percent (Figures 3 and 4) and 0.2 percent (Figures 5 and 6) chance of flooding in a given year. Note that the citywide assets addressed in this report are limited to those available through open data sources and identified as important facilities by City staff. Important direct effects of inland flooding exist for other vital community assets such as business corridors, places of community assembly, and housing, but these are not necessarily all considered here. Areas that have a one percent chance of flooding in a given year include the shoreline and southern edge of the city up to Bayfair Center. Most critically, sewer and transportation assets are exposed. The Livermore-Amador Valley Water Management Agency (LAVWMA) Valve Box, Roberts Landing Stormwater Pump Station, and the Marina Dechlorination Facility are all in the floodplain. In addition, the area between the Bay Fair BART station and Hesperian Boulevard is flooded under these conditions, including the BART parking lot, nearby retail locations and portions of the Caltrans East Bay Region Maintenance Station. The railways running through the center of the city and along the shoreline all cross the floodplain, as does a Pacific Gas and Electric Company (PG&E) powerline that runs through the marshlands. A number of community assets6 in the southwest part of San Leandro also have a one percent chance of flooding in a given year, including Dayton Elementary School which serves as a National Shelter System facility, James Madison School, the southeast corner of Saint Felicitas School, Washington Manor Middle School, and Woodroe Woods School. The Chinese Christian Church and Burbank Preschool are also close to the floodplain, and the Christ Presbyterian Church and New Life Church are in the floodplain. 3 Read, L. K., and R. M. Vogel. (2015). Reliability, Return Periods, and Risk under Nonstationarity. Water Resources Research, 51. doi:10.1002/2015WR017089. 4 The Bay Area Council. (2015). Surviving the Storm. Accessed at: http://documents.bayareacouncil.org/survivingthestorm.pdf 5 FEMA Flood Insurance Rate Map. (2009). 100 and 500-Year Floodplain. Alameda County. Effective August 3, 2009. 6 Community assets include business corridors, places of community assembly, schools and neighborhoods that have value to the community but are not emergency assets or part of core infrastructure. 49