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ATTACHMENT 4 To 05-06-04 Draft MWMC Minutes 1. The facilities plan project list allocates 38% of the cost of the headworks to growth. This is based on the generic application of percentages provided in' the SDC methodology. [This statement is incorrect. The 38% is not based on a generic application of the percentage provided in the SDC methodology. Per the SDC methodology for determining the improvement fee*cost basis, Steps I-2 and !-4 are explicitly prescribed in the methodology while Steps I- 1 and I-3 are case specific depending on which project in the 20.year project is being addressed.] According to the population projections on page 2-32 of the Facilities Plan, there is an expected population increase of just under 30% projected between 2005 and 2025. [The Facilities Plan and the SDC Methodology is based on population growth from existing (defined as 2002) to 2025. These values are 217,737 and 297,585, respectively, which result in a 36.7 percent increase.] According the discussion of the headworks on page 7-5, "the new facilities would be constructed to accommodate 160 mgd of dry weather capacity even though less capacity is required for total wet weather flows [The Headworks Expansion has been sized large enough so that the existing headworks will not have to be brought on and off line on a frequent basis in the dry season. This was done to avoid excessive operation and maintenance costs.] ." According to the SDC methodology, the maximum amount of additional dry weather capacity needed to serve growth through the year 2025 is 10 mgds (page C-1 of the methodology). Under the generic methodology allocation, preliminary treatment is allocated 25% to average flow and 75% to peak flow. It is also designated 100% to capacity· The methodology says that growth pays 100% of average flow and 29% of peak flow (which is another issue). If 25% of the headwork capacity is for average flow and the total capacity is 160 mgds, then growth would pay for 40 mgds of the dry weather capacity [This is incorrect for two reasons. First, only 50% of the total project cost for new headworks facilities are allocated to Preliminary Treatment. The other 50% are allocated to Peak Flow Management before the costs are allocated to average and peak flow. So the percentage of total project cost allocated to growth via average flow is 12.5% (50% to Preliminary Treatment * 25% to Average Flow). There is no cost allocation to growth via average flow for the other 50% of the project attributed to' Peak Flow Management. Second, aPPlying a system capacity parameter percentage allocation to some flow amount is irrelevant. The purpose of the SDC methodology is to equitably allocate the costs of projects between growth and existing users not to determine capacity. And even if that were correct the average flow allocation percentage (whether it be 25% or 12.5 %) could not be applied to the 160 mgd value because the 160 mgd value is not in average flow Units.], even though the methodology clearly indicates that the most dry weather capacity needed to serve growth during the planning period is 10 mgds. · The amount of peak flow needed to serve growth is identified as 30 mgds. We are allocated 29% of peak flow capacity. 75% of the headworks capacity is for peak flow under the methodology - 20 mgds. [This 75% is incorrect. As indicated above, 50% of the total project cost for new headworks facilities are allocated to preliminary treatment and 50% are allocated to peak flow management before the costs are allocated to average and peak flow. The percentage of Attachment 4 Page 2 of 17 4-5