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<br />CC Regular Session
<br />Meeting Date: 05/13/2014
<br />By: Bruce Westby, Engineering/Public Works
<br />Information
<br />Title:
<br />Review of estimated costs and funding program options for Garnet Street and 168th Avenue Reconstruction project.
<br />8. 1.
<br />Purpose/Background:
<br />Purpose:
<br />The purpose of this case is to review the preliminary estimated costs developed to date for the Garnet Street and 168th Avenue Reconstruction project, and to
<br />discuss and receive Council input on the proposed funding program for this project.
<br />Background:
<br />The segment of Garnet Street between 167th Avenue and a point about 300 feet south of 169th Lane NW, which measures approximately 1,350 feet in length
<br />and 32 feet in width, was originally constructed with bituminous pavement and curbing in 1988. The segment of 168th Avenue NW west of Garnet Street,
<br />which measures approximately 670 feet in length and 32 feet in width, was constructed at the same time using the same materials and design.
<br />Both streets are relatively flat and do not efficiently shed stormwater runoff which has resulted in fairly rapid pavement degradation, especially along the edges
<br />of the streets where stormwater collects. It also appears that both streets were constructed with a non-standard pavement section, but as is discussed later, this
<br />will be verified prior to completing the Feasibility Report.
<br />Both streets were sealcoated in 2006 and currently have a Pavement and Surface Evaluation Rating (PASER) of 1, which ranks them among the worst streets in
<br />the City in terms of pavement condition. In fact, large areas of Garnet Street are no longer paved and the City has been filling the non -paved areas with class 5
<br />aggregate to maintain the streets in as passable a condition as practical. And each spring when the ground thaws, the streets become extremely difficult to
<br />navigate and maintain due primarily to the poor underlying soils which become unstable when saturated with groundwater.
<br />On February 25th, Council authorized preparation of a Feasibility Report for reconstructing both 168th Avenue and Garnet Street by matching the existing
<br />alignments and geometrics. The only differences between the existing and proposed street sections is that the bituminous curb is proposed to be replaced with
<br />concrete curb and gutter, and storm sewer is proposed to be added to provide positive drainage. And as was discussed on February 25th, pedestrian facilities do
<br />not currently exist along either Garnet Street or 168th Avenue but are proposed to be constructed with this project. A 5-foot wide concrete sidewalk is proposed
<br />to be constructed along the east side of Garnet Street to connect the existing sidewalk that terminates at the north end of the project to the existing sidewalk
<br />along the north side of 167th Avenue. A 5-foot wide concrete sidewalk is also proposed along the north side of 168th Avenue that will connect the proposed
<br />Garnet Street sidewalk to the future sidewalk to be constructed with a future phase of the Brookfield development. The entire sidewalk system then connects to
<br />the bituminous trail on the west side of TH 47.
<br />Staff is also proposing to identify estimated costs for constructing sanitary sewer and watermain under both streets in case Council wants to bid these utilities as
<br />alternates when bidding the rest of the project. The bids could then be considered by Council to determine if utilities should be constructed with the project in
<br />anticipation that abutting property owners will want to connect to city utilities at some time during the design life of the streets, which is currently estimated to
<br />be 60 years if the proper subgrade corrections are made and routine maintenance is applied. Staff believes it is important to consider these costs as part of the
<br />Feasibility Report since public utilities are typically installed under City streets and adding utilities after a street is reconstructed would require much of the
<br />street to be reconstructed again. It may therefore be more cost-effective to construct public utilities with this project, even if the utilities remain unused for a
<br />decade or more.
<br />Current preliminary cost estimates for the various components of the project including streets, drainage, sanitary sewer, and watermain are shown below. It
<br />should be stressed that these preliminary cost estimates will likely change once additional information is received that will allow staff to complete the Feasibility
<br />Report and better determine estimated project costs.
<br />Preliminary Estimated Project Costs
<br />City Improvement Project 13-10
<br />Street Segment Street Drainage Sanitary Water Total
<br />Garnet Street $653,977.45 $142,425.00 $138,996.00 $142,202.25 $1,077,600.70
<br />168th Avenue $337,899.39 $48,978.00 $76,281.75 $79,628.40 $542,787.54
<br />Totals $991,876.84 $191,403.00 $215,277.75 $221,830.65 $1,620,388.24
<br />A Geotechnical Evaluation and Report, including several soil borings, must be completed to define the existing pavement sections, groundwater elevations,
<br />subgrade and topsoil compositions, and pavement design recommendations. Also, a proposed funding program must be developed, including proposed funding
<br />sources and percentages.
<br />In the past, the City has used a mix of funding sources to pay for street maintenance projects including the general levy, bonds, special assessments, and
<br />municipal state aid funds. Since a decision is still pending on whether Franchise Fees will be used to help pay for future street reconstruction projects, staff
<br />plans to complete the funding section of the Feasibility Report by recommending the standard mix of past funding sources. However, since assessments have yet
<br />to be applied to street reconstruction projects, staff would welcome Council input on what percentage to apply to special assessments. A minimum of 20% must
<br />be assessed per State Statute 429, and at the high end the assessment cannot exceed the benefit to the property. Since benefit can only truly be defined through
<br />an appraisal process which adds significant cost to a project, most cities that use assessments to help pay for street reconstruction projects typically apply an
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