Beginning with the 2007 report, the new per capita disposal measurement system (Chapter 343, Statutes of 2008 [Wiggins, SB 1016]) builds on AB 939 compliance requirements by implementing a simplified measure of a jurisdiction's performance.
The new system avoids base-year generation, taxable sales, or inflation issues by using disposal tons divided by population for 2007 and later years. Since statewide disposal and population data should be available by May of the year following the measurement year, the new method is faster and simpler. The new per capita disposal rate approach is not determinative of jurisdiction compliance but is just an indicator used in evaluating program implementation and local jurisdiction performance.
In 2007 there were two different Disposal Rate and Diversion Rate Equivalent numbers based on similar but slightly different calculation methods. The first calculation method used provided the disposal and diversion rate equivalent numbers reported at the CIWMB Board meeting on Dec. 16, 2008. This calculation method used the January 1 Department of Finance population total of 37.5 million residents, and federal fiscal year (October 1, 2006, through September 30, 2007) reported disposal of 39.6 million tons. This resulted in a 2007 Statewide Per Capita Disposal Rate of 5.8 pounds per person per day. Staff calculated this to be a 58 percent diversion rate equivalent.
In order to provide a benchmark that is consistent with the new methodology we require local jurisdictions to use, staff recalculated the 2007 statewide disposal and diversion rate equivalents. The January 1 Department of Finance population total of 37.5 million residents was still used, but the disposal amount was changed to the calendar year total of 39.3 million tons. This resulted in a 2007 Statewide Per Capita Disposal Rate of 5.7 pounds per person per day. Staff calculated this to be a 54 percent diversion rate equivalent.
The difference in diversion rate equivalents is due to the base against which progress is measured. The 54 percent rate was generated using the same four year average (2003 to 2006) for the statewide base that jurisdictions use. Now that we have a standardized methodology, the new methodology will provide results that are more consistent and more comparable from year to year. This change does not affect the official diversion rate for 2007 using the old goal measurement method, so it remains at 58 percent.
Statewide goal measurement from 2006 used population, employment, and inflation-adjusted taxable sales to estimate waste generation tons for each measurement year. This waste generation amount was compared to reported disposal tons to calculate an estimated diversion rate. Benchmark data for estimating measurement year statewide waste generation tons included all jurisdiction base-year generation amounts, many dating back to 1990. California Board of Equalization release dates for taxable sales data gradually increased from almost eight months after the 1996 measurement year to 12 months after the 2006 measurement year. See California's Estimated Statewide Diversion Rates Since 1995 graph for further diversion rate assistance.