2010 San Dimas System UWMP - Golden State Water Company

historic and projected demographic data for each census tract number from 2005 through 2035.Figure 2-2 details the census tracts within the San Dimas System.Annual estimates of historical population between 1997 and 2010 required for SBX7-7 areprovided in Table 2-1. The population estimates were developed following DWR TechnicalMethodology 2: Service Area Population. GSWC is considered a Category 2 water supplierbecause they maintain a Geographic Information System (GIS) of their service area. The perconnectionmethodology described in Appendix A of Technical Methodology 2 was used sinceannual estimates of direct service area population from SCAG or other local governmentagencies were not available. This method estimates annual population by anchoring the ratio ofyear 2000 residential connections to the year 2000 U.S. Census population. This ratio was thenlinearly scaled to active residential connections data to estimate population for the non-censusyears in which water supply data were available: 1997 through 2010. The residential billingcategory includes traditional single-family residential connections; however since GSWC doesnot have a specific multi-family billing category that only encompasses the apartmentcomplexes and other types of multi-family housing units, the ratio of year 2000 U.S. Censustotal population per residential connections was used for projecting population growth.Table 2-1:YearSan Dimas System Historical PopulationService Area Population1997 55,6701998 55,5341999 55,6102000 55,853 (1)2001 56,0552002 56,3242003 56,3972004 56,3242005 56,3742006 56,3432007 56,2862008 56,2072009 56,1802010 56,416Note:1. Population for year 2000 from 2005 UWMP.Page 2-6Final Report, 2010 Urban Water Management Plan – San DimasGolden State Water Companyg:\adminasst\jobs\2010\1070001.00_gswc-uwmp\09-reports\9.09-reports\2011-08\grp2b\gswc_sandimas_2010_uwmp-final.doc