Item C: General Obligation Bonds for Street Maintenance

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PAVEMENT PRESERVATION PROGRAM Street preservation, capital improvements, and maintenance efforts make up the complete Pavement Preservation Program (PPP). In this section, current cost analyses are shown and the roles of Public Works Engineering and Maintenance Divisions are discussed. Proposed projects for PPP are shown for 2008. Treatment Types and Costs Unit Costs were reviewed and updated in 2000 by Pavement Services, INC. In 2006, the Engineering Division updated unit costs as a result of various industry sources reporting substantial increases in construction costs. One reason for the increase was the cost of oil- based products. Staff reviewed cost trends provided by ODOT and noted that costs for liquid asphalt has risen over 77%, from $207/ton to $368/ton, in a nine month period. Public Works Engineering Division compared cost trend data with the current projects completed under the PPP program and recalculated unit costs to reflect recent price increases. After discussion with Pavement Services, INC., the 2% inflation factor appeared to be appropriate to continue to use once the unit costs were updated. 2007 unit costs used in the analysis are the updated costs with the 2% inflation factor. As of the date of this report, the costs for petroleum based products continue to climb steadily. Based on historic and current construction costs as tracked by the Engineering Division, each functional class has an estimated unit cost for overlay and reconstruction treatments. For Local streets (FC-5) an additional treatment option was considered: slurry seals. The slurry seal option allows for a cost-effective treatment for local street segments, which do not carry high traffic loads. Unit costs for overlay treatments are derived using historic weighted average project costs and projected costs for rehabilitation of streets in each specific functional classification. Typical overlay rehabilitation includes milling of existing pavement to a moderate depth to remove existing cracking and increase strength of the structural section. Isolated areas of severely distressed pavement is removed and replaced including a new aggregate base. Associated costs include replacement of striping and pavement markings, adjustment of manholes, and other work needed to return the street to normal operation. Unit costs for reconstruction treatments are derived using historic weighted average project costs and projected costs for reconstruction of streets in each specific functional classification. Typical street reconstruction includes removal of the existing pavement and base structural section and replacement with a new structural section which will meet a 20- year design life. Isolated areas of curb and gutter are replaced where they would not be suitable to contain new paving and/or have severe drainage problems. Associated costs include replacement of striping and pavement markings, adjustment of manholes, and other work needed to return the street to normal operation. Unit costs for slurry seal treatments are derived using historic weighted average project costs and projected costs for slurry seal of local streets. Typical slurry seal treatment includes street cleaning, removal of vegetation, sealing of cracks, and application of an emulsified asphalt 8