Project Title & Location
I-90 - Snoqualmie Pass East - Hyak to Keechelus Dam

Project Description
This project will improve I-90 to provide a safer, more efficient six-lane freeway from Hyak to Keechelus Dam. This project is the first of several projects that will address concerns along I-90 from Hyak to Easton. Avalanche closures and hazards due to rockfall will be minimized. Aging pavement will be replaced to provide a smoother ride. Expanded bridges and culverts will minimize wildlife collisions by providing safer crossings.

Contractor/Consultant
General Engineering Consultant: URS Corporation - Headquartered in San Francisco, CA

Recent Progress
The Hyak to Keechelus Dam project has been separated into six planned construction contracts scheduled to occur over multiple years. The first construction contract (Phase 1A) was awarded in March to KLB Construction Inc. with work slated to begin early this summer. This contract will construct a long term detour bridge at Gold Creek for eastbound traffic and will remove material from Keechelus Lake to provide irrigation storage mitigation. Final design of the second construction contract is on schedule for a fall 2009 advertisement date. Needed right of way purchases continue on schedule. There is limited geotechnical investigation work anticipated in 2009. Two additional test sections of wildlife fence were installed in October and we will evaluate their condition after winter snow melts later this spring.

Design Construction Impacts
The results of the 2008 geotechnical investigation work revealed a layer of liquefiable soils in the Gold Creek bridge area. Recommended mitigation at the Gold Creek bridge abutments has been proposed with the use of grout compaction columns, which will increase the cost of construction but should not affect the delivery schedule. Designers are evaluating the use of full depth concrete for the right hand shoulder along I-90. This would likely increase initial construction costs. However, an engineering analysis has shown that a cost savings will be realized over the life cycle of the roadway. The project office is continuing to work with geotechnical engineers on the design of a bridge and walls system at Slide Curve for the third contact (Phase 1C). Recent progress has revealed that all permanent walls in this system will need to be anchored into bedrock to overcome global stability concerns. The project office has started coordinating the mechanical, fire/life safety, drainage and ITS monitoring designs with HQ bridge for the snowshed. The additional design work will help define associated costs and impacts on the design and construction schedules.

Environmental Impacts / Compliance
For Phase 1B, we delivered the JARPA update to the agencies in March, and we will be determining whether to re-initiate ESA consultation in May.  We are gearing up our construction compliance program in order to be ready for the Phase 1A construction season, which will begin in June 2009.

Impacts to Traffic
No traffic control impacts due to pre-construction work are anticipated for the next quarter. Traffic control impacts are anticipated to start in summer 2009 as a result of construction work for the first contract, but should be limited to shoulder work or short duration lane closures. No impacts are expected due to geotechnical exploration.

Planned vs. Actual Expenditures
(Total Project Cost)

Nickel funds included in above costs

2005 Transportation Partnership Account