Item 4 - PH on MWMC Reg. SDCs - Laserfiche WebLink

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development is expressed in Flow Estimation Units, or FEUs. The loading placed on system capacity by a particular development type is reflected in the cost per FEU contained in the SDC rate schedule. The proposed SDC Schedule (Table S-l, included as Exhibit A to Attachment B of the AlS for the City Council work session of May 19, 2004, Agenda page 129), provides SDC rates for various development types as calculated following the proposed SDC methodology. To increase the accuracy of estimating a development's demand on system capacity and thereby improving the equity of the SDC rate structure, capacity in the treatment system is measured across four capacity types, or parameters. The four capacity parameters are Average Flow, Peak Flow, Biochemical Oxygen Demand (BOD), and Total Suspended Solids (TSS). The SDC schedule is developed by multiplying system-wide unit costs for each capacity parameter by the projected capacity requirement for each development category. Table 1 of this memorandum presents this calculation for five example development categories: 1. Single-family residential dwelling 2. Apartment building (60-unit) 3. General office building (20,000 square feet) 4. Low turnover restaurant (4,900 square feet) 5. Home improvement superstore (190,000 square feet) For each development type, and for each capacity parameter, the five steps taken to calculate the total cost per unit of development (size) include the following (with the corresponding line from Table 1 referenced): 1. User capacity x Unit capacity costs associated with = Reimbursement cost per FEU requirements (line 1) existing facilities (line 2) (line 3) 2. User capacity x Unit capacity costs associated with = Improvement cost per FEU requirements (line 1) new/future facilities (line 4) (line 5) 3. User capacity x Unit capacity costs associated with = Improvement credit for rate requirements (line 1) credit for rate support (line 6) support per FEU (line 7) 4. Add the results of steps I and 2, subtract the results of step 3 = total cost per unit of development (line 8) 5. Multiply the total cost per unit of development (line 8) x the size of the development = SDC for example development (line 9) For steps one through three in the SDC calculation process, the user capacity requirements of four capacity parameters (average flow, peak flow, BOD and TSS strengths) are multiplied by the associated unit costs to determine the total SDC. As each development type is assumed to contribute equal concentration of BOD and TSS, these are combined into a single strength category in Table 1. Appendix D of the proposed SDC Methodology (included in materials for the City Council work session of May 19, 2004, Agenda page 103), provides user capacity requirements for each of the development types included in the SDC Schedule. Appendix A of this memorandum provides further details on classes of strength of discharge used in user capacity requirements calculations.