When the new I-5/SR 502 interchange is completed in Washington State next year, not only will Battle Ground be directly connected to the interstate but a new entry and exit point also will have been provided for the limited access highway, shortening the route between the two roads and leading to reduced travel time. The opening of the interchange also will enhance the safety of travelers, particularly by reducing the number of vehicles backing up on the northbound I-5 off-ramp at SR 502.
The Washington State Department of Transportation (WSDOT) completed a 24 month study of the I-5/I-205 corridor in 2001. During its investigation, it identified interstate and interchange needs of the northern Clark County area, and the plan that was subsequently developed recommended a new I-5 interchange be constructed at this location.
The approximately 150-acre (60 ha) job site is located within what is legally known as the Cowlitz Tribe’s usual and accustomed area. A vast amount of land across the Pacific Northwest, and in the state of Washington in particular, has historic ties to various Native American tribes, and the Wisconsin State Department of Transportation recognizes their affiliation with land on which work is carried out. As part of departmental environmental protocol, inadvertent discovery plans provide guidance on procedures to be used when artifacts or remains are found in the course of a project.
In this particular case WSDOT, the Cowlitz Tribe, the Federal Highway Administration (FHA), and the Washington State Department of Archaeological and Historic Preservation cooperated on how to handle such matters. Some artifacts were discovered during construction but details are protected, so their location or other specifics will not be revealed.
By August 2005 the department’s environmental assessment had been completed and was available for discussion. In October 2005 the Federal Highway Administration issued a No Significant Impact Finding, and over that fall and winter the final design for the project was completed. Right-of-way acquisitions were accomplished by fall 2006.
Part of the funding for the job comes from an unusual source: the Nickel Package, a gas tax approved by Washington State voters in 2003. Nicknamed The Nickel, the initiative’s slogan is “It’s Your Nickel, Watch It Work.” Money raised under the five cents a gallon tax increase will fund 158 projects statewide over ten years. When they are completed and associated bonds are paid off, the five cents tax increase will be removed.
The Nickel contributed $51.4 million to the cost of the interchange, and local funding added $378,000. The overall value of the contract, which included a sizable amount associated with real estate and right-of-way acquisition, includes approximately $30 million in construction costs and $20 million in engineering, design, inspection, and contract administration.
Kerr Contractors Inc., based in Woodburn, Ore., is general contractor, having been awarded the contract in February 2007.
Construction began that year with a groundbreaking ceremony on April 12 attended by WSDOT Southwest Region Administrator Don Wagner, Cowlitz Tribe Chairman John Barnett and Vice Chairman Mike Iyall, Battle Ground Mayor John Idsinga, Tim Kerr, vice president of Kerr Contractors Inc., and other dignitaries.
At the event, which took place on a gravel road near I-5, it was noted the project was located not far from a path used by the Cowlitz Tribe’s ancestors to travel between the Columbia River and Puget Sound.
The interchange opened to vehicles in October and is scheduled to be completed by summer 2009.
During the summer of 2007 Kerr Contractors Inc. placed the first leveling course of pavement to preserve and stabilize the site from the fall and winter rainy seasons. Parts of the project needed aeration to meet specified compaction due to high water tables, while some areas required re-excavation and backfill because subgrade had been affected by underground springs. The focus of construction that summer was to maximize work on grading, surfacing, drainage, utilities, and the superstructure for the interchange bridge.
Equipment used on the job included two Hitachi 800, two Kobelco 400, a Volvo 330, and Caterpillar 315 and 320 excavators. Caterpillar 623 and 615 scrapers and D5 and D8 bulldozers also were utilized, as were Komatsu D61 and D38 dozers. In addition, a Caterpillar 834 sheepsfoot compactor and 84-in. (213 cm) Ingersoll Rand and Sakai compactors worked on site as did JD 544 and Caterpillar 980 loaders, along with six Volvo A40 haul trucks and Kenworth tractors with side dump trailers.
Milling operations were carried out by a Wirtgen W-50 utility grinder and Wirtgen W-1200, W-2000 half lane or 7-ft. (2.1 m) cut and W-220 or l2.5-ft. (3.8 m) cut milling machines. The milling machines were all equipped with the Flex-Cutter option, allowing variable width milling capabilities. Cement treatment was handled by a Wirtgen 2500 Pulva-Mixer with a custom designed cement spreader truck.
Kerr Contractors Inc. also fielded a JD 850 bulldozer and Caterpillar 140G and JD 872 and 140 H graders fitted with Topcon Positioning Systems Global Navigation Satellite Systems (GNSS).
These systems involve a pole-mounted antenna and a receiver attached to the equipment. Satellites send positioning data to a similar antenna and receiver at a fixed location often referred to as a base station. The base station corrects for GPS position errors and sends this information to the equipment working on the job site. Inside the cab of the machine the finish design grades are stored in an on-board control box. The control box continuously compares the current location of the machine to the design elevation, sending raise/lower signals to the hydraulic valves keeping the cutting edge of the blade on grade. Elevation and slope are automatically controlled anywhere as the equipment moves on the site. GPS systems were supplied by the PPI Group, based in Portland, Ore.
The project involved clearing and grubbing 80 acres (32.4 ha), with 210,000 cu. yd. (160,560 cu m) of soil excavated for the roadway and 120,000 cu. yd. (91,750 cu m) for embankments. 8,100 linear ft. (2,470 m) of drainage was installed and 3,000 ft. (910 m) of water line. 90,000 tons (81,650 t) of crushed surfacing base course and 57,000 tons (51,710 t) of hot mix asphalt also were used for the job.
As part of the contract, Kerr Contractors Inc. was required to remediate 40 acres of federally protected wetlands impacted by the interchange. Large holding ponds will gradually release storm water to a sloping geogrid area covered with tree cuttings. After undergoing bacterial action caused by flowing over these cuttings, the water will find its way to a nearby creek, thus recreating the natural wetland process. This part of the job required excavation of 57,000 cu. yd. (43,580 cu m) for the ponds and 132,000 cu. yd. (100,921 cu m) for the wetland.
“The site will provide 12 surface acres of headwater storage to the Gee Creek watershed, meaning that the site will retain a larger volume of water for longer periods of time into the spring than current conditions, which will provide a longer duration seasonal base flow contribution to the Gee Creek tributary downstream of the mitigation site,” stated Dan Corlett, Washington State Department of Transportation Southwest Region Roadside and Environmental Restoration Manager. “At a 1 foot depth, this represents nearly 523,000 cubic feet or 3.9 million gallons of potential surface water storage across the site.”
The task required 12 acres of wetland creation (excavation), 5 acres of wetland enhancement (some excavation and geogrid), and 17 acres of upland buffer (side slopes, perimeter berms and soil preparation areas).
The interchange project also involved construction of an approximately 740-ft. (225 m) long $6.2 million bridge. Subcontractor for the job was Cascade Bridge LLC of Vancouver, Wash.
Begun in May 2007, bridge girders were placed at the beginning of 2008 and by March deck work was in progress. The bridge was completed in July, despite a delay of several weeks due to winter storms.
Primary work remaining on the project involves landscaping and traffic signs, placement of which began the week of September 15. Traffic striping was completed the same week. CEG