75B - PH - METERED WATER RATE AND SEWER CHARGE

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Sewer Infrastructure C.I.P. Considerations The City's sewer system consists of approximately 390 miles of sewer mains, 45,000 laterals, and 7,600 manholes. Approximately 185 miles of mains, or more than 47% of the existing sewer mains are over 50 years old. In addition, 86 miles of the existing sewer system is 6" pipe which is not in line with today's standards. The Water Resources Division is using other technologies to extend the life of existing sewer mains. Where feasible, mains, laterals and manholes are being lined using various processes as appropriate. Age of Sewer Mains 6" Diameter Sewer Mains - " ~ ¦ 50+ Years Old ¦ 6" Mains ` ¦ Rest of System ¦ Other he service life of sewer mains is assumed to be 50 years. With 390 miles, we should be replacing For preliminary estimation purposes, t at least 8 miles per year. For purposes of calculating a rough budgetary estimate of the replacement cost of the entire sewer collection system, the following assumptions will be used: All new sewer mains will be 8" diameter. This will result in a low estimate, since many pipelines are larger than 8" (Our system includes lines from 8" to 24" in diameter, however 97% are 15" and smaller). The cost for 8" sewer main is $140 per linear foot, the cost of a lateral is $4,800, and the cost to replace a manhole is $6,000. The above costs are construction only. They do not include design, inspection, street repaving, or other contingencies. The total figure shown below includes an additional 35% to account for these items (10% for design, 10% for inspection, and 15% for repaving and contingencies). Based on the above figures and assumptions, the total replacement cost of the sewer collection system is approximately $742,000,000. Assuming that 8 miles per year are replaced (50 year replacement cycle), then the annual sewer CIP would need to be $14.8 million. We are planning to spend $2.4 million during FY 2010/11 for sewer CIP improvements. Capital Improvement Costs $14.9 M $15,000,000.00 ~ ~ - I $10,000,000.00 - - 2.4 M $5,000,000.00 - ' ~ -w FY 2010/11 CIP 50 Year Replacement Cyle Exhibit 3 75B-9