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Pavement Life Maintenance Costs <br />This analysis compares the cost of asphalt and concrete pavement for the Almond Grove project <br />over the life of both of these pavement solutions. This analysis differs from those at previous <br />Council meetings as the costs are presented in today's dollars. The analysis looks at the <br />difference in initial construction cost in comparison with anticipated future maintenance and <br />rehabilitation costs. In summary, the historical performance for the concrete option indicates that <br />little maintenance will be required over the next 50 years. Asphalt pavement requires more <br />future maintenance and rehabilitation over the same period of time, which includes crack sealing <br />and surface seals at periodic intervals. At the end of its initial service life, more extensive <br />pavement rehabilitation is anticipated with asphalt, which could include a full overlay or <br />reconstruction. These future maintenance and rehabilitation activities result in higher future <br />costs over the 50 year period. <br />During the 2010 conceptual design phase, staff estimated the future maintenance costs using <br />industry practice for maintenance of asphalt streets. The Town's anticipated maintenance <br />practice is based on expected resources and other Town -wide priorities for street repair, therefore <br />at this time staff is assuming a less rigorous treatment schedule. The treatment schedules are as <br />follows: <br />Industry Standard Asphalt Maintenance Program: 7 year Slurry Seal, 14 year Slurry Seal, <br />21 year Slurry Seal, 28 year Overlay, 35 year Slurry Seal, 42 year Slurry Seal, and 49 <br />year Slurry Seal <br />Town Practice As halt Maintenance Program: 10 year Slurry Seal, 20 year Slurry Seal, <br />30 year Rubber Cape Seal, 40 year Overlay, and 50 year Slurry Seal <br />Concrete Maintenance: Industry standard of 3% slab replacement every 14 years <br />Based on these maintenance schedules, staff from the Finance Department and Town Manager's <br />Office worked with Parks and Public Works to develop estimated life cycle costs for asphalt and <br />concrete. The following assumptions were made to calculate these costs: <br />1. 50 year life cycle <br />2. Inflation rate of 3% per year for increased cost of supplies, services, etc. <br />3. Effective Annual Interest Rate of I%. A rate I% was selected as this is the approximate <br />interest rate that the Town is earning today. The calculations that were done reflect net <br />present value which is how much money the Town would need to put aside today to <br />accumulate enough money over the course of the 50 year life cycle to pay for the <br />projected maintenance costs. <br />4. Broadway and Bachman have full designs, including the amount (quantity) of pavement. <br />The other streets have a conceptual design, which is much higher level, and provides <br />estimates on the amount of pavement. Future maintenance costs for the remaining eight <br />streets would be reflective of these estimated quantities and costs. The life cycle <br />estimates provided assume similar costs for all ten streets. <br />ATTACHMENT <br />