Major projects recently completed or now under way on the SR 18 corridor represent an aggregate budget of approximately $163 million.  With work on the projects completed in some cases, and in various stages of completion in others, the current estimate of the total final cost of construction for these projects is $165 million.  The total estimate of completion for all projects therefore stands at approximately 1.4% over the total $163 million budget for the projects.

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Federal Way – Adding a westbound truck climbing lane up Peasley Canyon between Auburn Way and SR 167, involving significant roadway re-alignment.  Work includes bridge extensions, slope stabilization on the canyon wall above the highway, stormwater runoff protection and traffic cameras.  New traffic signals are being added for the Weyerhaeuser Way ramps.  Construction will be completed in the fall of 2005.  Construction costs are on budget except for the new ramp signals, for an overall expected construction cost of $18.8 million, about $700,000 under the $19.5 million construction budget. 

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Auburn - Widened the eastbound SR 18 off ramp to the West Valley Highway and added a new lane on West Valley Highway to Peasley Canyon Road.  Construction was completed on schedule in May 2005 and on budget at $1 million.

Also in Auburn, 5.2 miles of SR 18 are being paved between “C” Street SW and SE 304^th Street, together with drainage and erosion control improvements at Black Diamond and SR 164/Auburn Way interchanges.  On time completion is expected in October 2005 at an expected final construction cost of $4.9 million, slightly (4%) over the construction budget of $4.7 million. 

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Covington - Added two new lanes on a 5.5 mile segment from Covington Way to Maple Valley, including a new interchange at SE 256^th Street, major  bridge work on the mainline, local street improvements on  SE 240^th Street, stormwater runoff protection and noise walls.  Bridges were constructed to replace culverts at stream crossings to enhance fish passage.  The project was open to traffic on schedule in October 2002.  Completion of erosion control and landscaping is now under way in a Nickel Fund project.  The total expected construction cost of $51.1 million is about 4% under the construction budget of $53.3 million.

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Maple Valley - Adding two new lanes to continue the corridor improvement program for a three-mile segment between Maple Valley and Issaquah/Hobart Road.  Work includes a new interchange at 244^th Avenue SE, removing two intersections, extensive realignment of all lanes, and associated bridge extensions or replacements.   The project also includes stormwater runoff protection and wetland replacement for wetland areas taken for highway right-of-way.   The project is expected to be open to traffic in summer 2006.   The current estimate of total construction costs at $86.1 million is $5.3 million or 7% over the original construction budget, principally because unexpected soil conditions required higher than anticipated quantities of soil export and import during the earthwork portion of construction.

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