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<br />7A - ATTACHMENT NO.3 <br />Saltworks Proposal- Water Group Summary Report (22 January 2010) Page 13 <br /> <br />Because of the complexity of the demand factors used by DMB for the C&I indoor <br />category, the detail of those factors is not repeated in this report, but can be found in the <br />DMB Demand Report. However, the water team is prepared to discuss these factors <br />and answer questions from the City. <br /> <br />2.2.3 Landscape Irrigation Demand <br /> <br />This category of land use is segregated in the DMB Demand Report into residential <br />landscape, C&llandscape, and "public landscape." The public landscape category <br />includes a sports complex, neighborhood parks, and streetscape and roadway medians. <br />The residential category includes all common area landscaping for the residential <br />developments, and the C&I category includes all exterior landscaping for this land use. <br /> <br />Residential outdoor water use factors were estimated using the University of California <br />Cooperative Extension and the California Department of Water Resources (UCCE/DWR) <br />landscape irrigation model, which incorporates the Saltworks specific water-efficient <br />technologies and landscape design techniques. This model uses vegetation-specific <br />irrigation water requirements using evapotranspiration factors, landscape coefficients, <br />precipitation, and irrigation efficiencies. The DMB Demand Report uses City-specific <br />data for evapotranspiration and rainfall. The model separates landscaping into two <br />categories: high water use plantings (turf grass and some ornamental landscaping) and <br />low water use plantings (shrubs and native vegetation). The annual irrigation <br />requirements for high water use plantings are 3.3 AFY/acre, and the irrigation <br />requirements for low water use plantings are 1.5 AFY/acre. Assumptions were made by <br />DMB regarding the total area of each respective planting assumed for each residential <br />product type. <br /> <br />C&I outdoor water use was assumed by DMB to be a percent (27 percent) of the total <br />water use for each of the C&I land uses. This assumption was based on information <br />reported in the Pacific Institute study, as well as estimates of the conservation savings <br />for indoor and outdoor water uses. <br /> <br />Public landscaping within the Saltworks project includes a sports field complex, <br />neighborhood parks, a 4-H club and farm, a multi-use open space, school parks, and <br />streetscapes and roadway medians. The volume of water used to irrigate these areas <br />was estimated using the same methOdology and model (UCCE/DWR) that was used to <br />develop the residential outdoor water use factors described above. <br /> <br />Based on the methodology and results presented in the DMB Demand Report, the <br />anticipated demands for landscape irrigation. are as follows: <br /> <br />· Residential Landscaping - 200 AFY <br />· C&I Landscaping - 70 AFY <br />· Public Landscaping - 580 AFY <br />· Total Landscape Irrigation Demand - 850 AFY <br /> <br />All outdoor landscape irrigation demands are assumed to be met with recycled water. <br /> <br />6 <br />