SR 8 - New McCleary interchange
Grays Harbor County
The $4.6 million McCleary Interchange project constructed a partial cloverleaf interchange. This eliminated an intersection at SR 8 where local traffic on the Mox-Chehalis Road had to cross several lanes of highway traffic in order to enter the highway, or to cross. The project, located 13 miles east of Olympia, improves traffic flow by eliminating cross-movements on SR 8 and resolves a high-accident location.
Construction summary
The interchange was constructed in three stages. The first stage built a new bridge over SR 8 and partially constructed the interchange’s new on- and off-ramps. Traffic on Mox-Chehalis Road was allowed to cross SR 8 on the new bridge, but vehicles exiting and entering SR 8 still had to use the existing intersection. Stage 2 construction completed the southern on- and off-ramps. Stage 3 completed the northern on- and off-ramps.
The contractor and WSDOT worked closely together on the project and were able to resolve the many issues that came up during construction. For example, the contractor proposed setting the girders for the new bridge in the daytime and establishing a daytime detour through the City of McCleary. This improved safety for the traveling public and reduced costs by not having to staff up for both night and day shift work.
Major problems arose that added to the contract cost. The areas of soil removal (dig-outs) were expanded due to the discovery of unsuitable soils, such as clay. The extent of dig-out areas was larger than what had been estimated in the plans, and was unknown until excavation was under way, during construction of the new ramps. Additional quarry spalls, geotextile material and fill material were needed in the areas where soft soil was found. The amount of fill material required to construct the new interchange was also more than estimated in the plans. The extent of soft soils would have been hard to identify even with more extensive soil borings.
Traffic control costs were underestimated in the contract. The three stages needed to construct the interchange required additional hours of traffic control and flagging. The contract was scheduled to “winter-over” at the end of Stage 1 with contract time being suspended and no work being done in the winter. The contract was advertised for bids late in the summer of 2002. Because of the late ad date, the contractor did not reach the end of Stage 1 until June 2003. This meant the contractor worked through the winter of 2002-2003 constructing the new bridge and the dirt work became the critical path item on the schedule. Wet winter weather stopped dirt work operations for 3.5 months. During that same time the contractor continued working on constructing the bridge and the additional traffic control charges continued to accumulate along with additional inspection and administrative charges.
The teamwork between the contractor and WSDOT was very good. A team approach was utilized involving both WSDOT and the contractor’s personnel to resolve issues quickly and efficiently.
The public and was informed through weekly press releases. We also kept the City of McCleary officials updated with regular meetings and phone calls on project progress.
Lessons Learned:
Overall more time spent in design of the earthwork quantities would have made the estimate of fill quantities closer to what was actually used. Also, more work in defining the traffic control needed to construct each of the stages for the interchange would have helped identify the amount of traffic control needed.
Contractor:
Scarsella Brothers, Inc., Seattle, WA
WSDOT Contact:
Project Engineer, Kurt R. Williams
Phone: 360-570-6752.
Email address: willikr@wsdot.wa.gov
 back to top
|