Agenda - Council - 10/23/2018 - Laserfiche WebLink

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Our !Almon: To work together to respcaibty grow Our community, and to provide quality, COM4ffeciive, and efficient government invoices. CC Regular Session 7. 9. Meeting Date: 10/23/2018 By: Bruce Westby, Engineering/Public Works Information Title: Adopt Resolution #18-221 Accepting Feasibility Report and Ordering Public Hearing for Improvement Project #19-03, Wood Pond Hills and Chestnut Ridge Street Reconstructions Purpose/Background: Purpose: The purpose of this case is to consider adopting Resolution #18-221 accepting the Feasibility Report and ordering a Public Hearing for Improvement Project #19-03, Wood Pond Hills and Chestnut Ridge Street Reconstructions. Background: City Improvement Project No. 19-03 proposes to reconstruct streets within the Wood Pond Hills and Chestnut Ridge neighborhoods including 146th Avenue, Helium Street, and Krypton Street. The streets total approximately 3,310 linear feet (0.63 miles) in length. A map showing the location and scope of the proposed improvements is included as Figure 1 in Appendix A. The streets were constructed between 1992 and 1994 with bituminous pavement, surmountable concrete curb and gutter, and concrete storm sewer. The streets were constructed to a width of 30-feet from face -of -curb to face -of -curb, and are centered within a 60-foot wide right-of-way. The existing bituminous pavement section ranges from 1.6 to 5.0 inches thick, with a median thickness of 2.5-inches. This was determined from Ground Penetrating Radar (GPR) analysis performed by Braun Intertec in 2017, as well as from field observations and record plan documents. Copies of Braun Intertec's GPR results are attached in Appendix C. The pavement section was built on generally poorly graded sand with silt subgrade material generally considered usable for pavement support with proper conditioning. City staff evaluates and rates the condition of pavement sections on all City streets on an annual basis using the Pavement Surface Evaluation and Rating (PASER) system. In the summer of 2018, the pavement sections of the above referenced street segments were rated with a PASER rating of 2, with the exception of the south half of Krypton Street receiving a rating of 4. Ratings of 4 and below indicate these streets require complete reconstruction. City Staff patch the streets at least once per year, particularly before winter so the streets can be plowed without further damaging the pavement in the process. Pictures of the streets are located in Appendix A. Proposed improvements include removing and replacing all damaged concrete curb and gutter sections, and reconstructing the existing bituminous pavement section using the Full Depth Reclamation (FDR) process. This process would involve reclaiming the entire existing bituminous pavement section, along with the existing aggregate base. This reclaim material would then be spread over the reshaped and compacted subgrade between the curb and gutter, then the top 3 r/2 -inches of reclaim material would be removed and hauled off site, after which 3 r/2 -inches of new bituminous pavement would be installed over the remaining compacted reclaim material. This would result in a 7-ton pavement design, which is standard for residential streets. Existing sanitary sewer and watermain infrastructure are in good condition. The existing storm sewer system is also in good condition with only minor work being proposed. The engineer's opinion of probable costs for completing the proposed improvements outlined in this report is $372,236.52. Estimated costs include 5-percent contingency costs plus 23-percent indirect costs for administrative, engineering, finance and legal costs. A summary of the engineer's opinion of probably costs is included in Appendix B. A total of 59 assessable parcels have been identified. Staff recommends applying 25-percent of the eligible project costs equally across the 59 assessable properties using the "per lot" assessment method. Eligible project costs include everything except subgrade correction costs. This results in a proposed preliminary assessment