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SYSTEM DEVELOPMENT CHARGE METHODOLOGY · Average flow · Peak flow · BOD · TSS These parameters are defined as follows: · Average Flow-The average daily flow in the dry season as defined in the National 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 h qow (I/I). · Peak Flow--The peak hour flow in the wet season associated with the 5-year, 24-hour storm event. Peak flow includes average flow and the additional increment of wet weather I/I. · Biochemical Oxygen Demand-The quantity of oxygen used in the biochemical oxidation of organic matter in a specified time and at a specified temperature. BOD is a measurement of wastewater strength. · Total Suspended Solids--Solids in the wastewater that are removable by laboratory 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. Table 3 provides the allocations of existing and future facility process components to the system capacity parameters: average flow, peak flow, BOD, and TSS. A description of process components is provided in Appendix A. The rationale for the allocation percentages is provided in Appendix B. These allocations are used to determine the projected costs of capacity to be used by new development that establish the reimbursement fee and improvement fee cost bases. The underlying approach is to evaluate the following criteria for each facility process component: · Functional performance · Design basis The functional performance criterion considers the actual purpose of the facility on a daily basis. Is the purpose of the facility to remove BOD or TSS from the wastewater? Or is the purpose of the facility to simply pass the flow (average and/or peak) and remove some other parameter not represented by BOD or TSS such as screenings, grit, or pathogens? These questions are answered by the functional performance component. The design basis considers what system capacity parameter or combination of parameters drives the sizing of the facility and, therefore, the constructed cost. The allocation basis for each facility component presented in Table 3 combines both the functional performance and design basis considerations. In addition to these system parameters, because there can be projec.ts that provide overall support for the wastewater system, a separate category of "indirect" support facilities is used to provide for reallocation of these support-type costs across all of the system capacity parameters. SEA31003271388(DG).DOC~041040034