Item 2C: Adoption of Resolution Amending MWMC Regional Wastewater SDC Methodology

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? Does not recover the costs of the same capacity through the reimbursement and improvement fees. Recovers cost associated with existing capacity through the reimbursement fee, and recovers costs associated with new capacity through the improvement fee. The charges to individual developments are based on a weighted average cost of capacity. Each element of the methodology is discussed in more detail below. Methodology Element One: Determine Growth Capacity Needs Oregon SDC law requires explicit analysis of capacity required to serve growth—and demonstration of how those capacity needs will be met through existing and future facilities. Therefore, it is necessary to first determine the appropriate capacity parameter(s), and growth’s capacity requirements. Step One - Capacity Parameters The appropriate capacity measure relates to the sizing criteria of the wastewater system, and may, to improve equity, require consideration of multiple parameters to assess the impact of the utility’s various types of users. As wastewater systems must be sized to meet all of their customers’ demands, flows and strength loadings are important sizing criteria. MWMC provides service to a diverse customer base, so consideration of varying flow and load requirements of different customer types is one facet that ensures the equity of the SDCs. The four capacity measures or parameters used in the methodology are: ? Average flow ? Peak flow ? BOD ? TSS These parameters are defined as follows: ? —The average daily flow in the dry season as defined in the National Average Flow Pollution Discharge Elimination System (NPDES) permit. Because the NPDES permit requires the Eugene-Springfield Water Pollution Control Facility (WPCF) to meet permit discharge limits on a monthly basis, the average flow is presented in terms of dry season maximum month values when discussing “capacity.” The dry season maximum month flow includes base flow (customer flow) and the baseline or dry season infiltration and inflow (I/I). ? —The peak hour flow in the wet season associated with the 5-year, 24-hour Peak Flow storm event. Peak flow includes average flow and the additional increment of wet weather I/I. ? —The quantity of oxygen used in the biochemical Biochemical Oxygen Demand oxidation of organic matter in a specified time and at a specified temperature. BOD is a measurement of wastewater strength. ? —Solids in the wastewater that are removable by laboratory Total Suspended Solids filtering and approximate the quantity of solids that are available to be removed from the wastewater through sedimentation. TSS is a measurement of wastewater strength. Page 9 OF 39