Evergreen Corridor Pavement Plan Southeast Chelsea Avenue to Southeast 164th Avenue City of Vancouver, Washington May 2017 INTRODUCTION This report presents the City of Vancouver’s (City) pavement plan for the Southeast Evergreen Highway Corridor, a 20-foot-wide, Portland cement concrete (PCC) roadway that was constructed in 1919 and 1920. The first paved roadway in Clark County, it was built to the standards at the time with concrete panels and no shoulders. The roadway was experiencing deteriorating conditions even before being annexed by the City in 1997. Asphalt overlay was applied in many areas to help improve the driving surface, but over time and with increased traffic, that became rough and uneven. The extensive cracking and deterioration result in very rough riding conditions for bicycles and vehicles. The pavement has been further impacted by water infiltration through the severe cracking, affecting the subgrade and causing freeze/thaw damage during winter. As noted in the Evergreen Corridor Management Strategy, “One of the top priorities for residents is to see the roadway improved to create a smoother riding surface and ensure maintenance is provided on a reasonable cycle.” This report sets forth the plan for addressing pavement along the section of the corridor that is approximately 5 miles long, extending from Southeast Chelsea Avenue east to Southeast 164th Avenue, as shown on the attached Evergreen Corridor Pavement Management Plan Map. The corridor section Southeast 164th Avenue to the city limits, not part of this report, will be addressed after the section from Southeast Chelsea Avenue to Southeast 164th Avenue has been resurfaced.
EVALUATION In recent years, the City has evaluated the corridor through engineering studies, pilot projects, and street maintenance efforts. Engineering Studies In 2016, the City contracted with GRI to perform a pavement evaluation of the corridor to analyze the existing PCC roadway and provide recommendations for resurfacing the corridor. The results of their evaluation are presented in their report dated Aug. 12, 2016. The following is a list of their primary findings. o The existing concrete slab is about 5 to 7 inches thick (6.5 inches on average) and lies directly on silty sand. o There is good joint transfer between slabs. This will help slow down reflective cracking of an asphalt overlay above the joints between slabs. o There was no rebar encountered in the slab in the core holes. However, rebar has been encountered in the slab by City Public Works maintenance crews at the Mill Creek Culvert crossing near Southeast 101st Avenue and during other utility work near Southeast 164th Avenue. o GRI recommends reconstruction of the PCC roadway if funds are available. Less preferred alternatives are a 3-inch overlay, or microsurfacing. The City retained consultant Otak Inc. to prepare planning-level cost estimates of four corridor replacement options that involved removing the existing concrete and then paving. Replacement options included full-depth hot mixed asphalt (HMA); a crack-and-seat process with HMA overlay; pervious concrete; and full-depth Portland Cement Concrete Pavement (PCCP). Of these options, Otak recommended removing the existing concrete and paving as the most reasonable approach. Construction costs for this option ranged from $18.6-$23.1 million, which equates to about $320-$395 per square yard. Otak’s results are presented in their Technical Memorandum dated March 7, 2016. DKS Associates performed a study of existing traffic conditions along the corridor for the City. Those results are presented in their memorandum titled, “Evergreen Corridor Plan Transportation Technical Memo”, Jan. 22, 2016. The main finding substantiates that most traffic flow occurs between Southeast 164th Avenue and Ellsworth Road, and that there is less traffic west of Ellsworth. In addition, most of the traffic is from passenger vehicles, with 2
minimal local delivery trucks. Other findings in the memorandum pertain to traffic calming plans