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HomeMy WebLinkAbout05/04/1999, C6 - STREET RECONSTRUCTION/RESURFACING-SPRING 1999 SPECIFICATION NO. 90011 council m � j ac Enna uEpout 4m Nb. CITY OF SAN LUIS O B I S P O FROM: Michael D.McCluskey,Public Works Director Prepared by: Daniel Van Beveren,Civil Engineer SUBJECT: Street Reconstruction/Resurfacing—Spring 1999 SpecificationNo.90011 CAO RECOMMENDATION: 1. Approve plans and specifications for"Street Reconstruction/Resurfacing- Spring 1999". 2. Authorize staff to advertise for bids for"Street Reconstruction/Resurfacing- Spring 1999"and authorize the CAO to award the contract if the lowest responsible bid is within budget DISCUSSION: The City's Pavement Management Plan(PMP)was adopted by the City Council on April 14, 1998. The key elements of the PMP are the establishment of eight principal areas within the city, and a maintenance plan in which each of these eight areas will receive maintenance over an eight-year period. Streets which are classified as arterial or collector,as well as streets located in the central downtown area are not part of this rotation because they require maintenance more frequently. In 1998,Nichols,Vallerga&Associates(NVA),a private consulting firm specializing in pavement design and maintenance,was awarded a contract for engineering services,per Specification 9217. NVA performed structural testing of selected City streets primarily located in pavement areas 1 and 2. The streets tested were those which had been selected for rehabilitation based on the City's PMP which utilizes the computer program MicroPaver. NVA conducted the tests using the falling weight deflectometer method, a nondestructive testing method of determining a street's structural integrity. As part of their contract with the city, NVA issued their findings in a report, "Falling Weight Deflectometer(FWD)Testing and Street Rehabilitation Evaluation of Various Streets",in which test results and design recommendationswere presented. NVA then completed plans, specifications, and engineer's estimate for "Street Reconstruction/ Resurfacing,Fall 1998." The construction of this paving project has just been(or is very nearly) completed. City Public Works Engineering staff has now completed the plans, specifications,and engineer's estimate for "Street Reconstruction/Resurfacing— Spring 1999". These plans and specifications present the design of street improvements for most of the remaining of the streets included in the above-mentionedNVA pavement testing report. This project includes several streets that will receive a full thickness asphalt reconstruction. It is important that we do this reconstruction work in the dry season when the chance for exposed subgrade soil to be impacted by rainfall is minimal. Also included in this project is the replacement C6-1 Council Agenda Report—Street Reconstruction/Resurfacing,Spring 1999-90011 Page 2 of an existing cross gutter (at the comer of Mill Street and Grove Lane) with an underground drainage structure. This improvement will bring the intersection current with City standards. Some streets on this project will benefit from recent advances in asphalt concrete technology. An asphalt-reinforcing grid will be used on a few of the streets in which the NVA report had recommended full thickness asphalt reconstruction. The grid, which acts similar to rebar in reinforced concrete,provides a tension member in the asphalt and will eliminate the need for a full thickness asphalt reconstruction. A gap-graded mix of rubberized asphalt will be used on other streets. Compared to traditional asphalt,rubberized asphalt has higher strength,yields less vehicle noise,stays black longer,recycles used automobile tires,and will save money by allowing us to use a thinner overlay thickness in the design. Applying these advances in pavement technology to our pavement maintenance program will help to extend the life of the pavement system in a cost- effective manner. CONCURRENCES: The Community Development Department has approved this project for environmental clearance. FISCAL IMPACT Estimated Construction Cost Engineer's Estimate $1,260,208 Contingencies(10%) $126,000 Total $11386408 Balance of Construction Funds Available $1,665,558 (1997-1999) ATTACHMENTS: Project Location Map Plans and Specifications for"Street Reconstruction/Resurfacing— Spring 1999"— available in the Council Read file 1:1COUNCIL AGENDA REPORTS X90011 C6-2 KA-11 MF mm MON -Pill.