Mowat Construction Company: Piling Foundations - 
- Alaska
- Washington
- Fremont Bridge
- Newport Way to I90 Widening
- Green River Bridge
- Snohomish Machias Bridge
- Sauk River Bridge Replacement
- York Bridge Replacement
- Aurora Bridge
- Edgewick Bridge Replacement
- SR 16, Union to Jackson Steel
- High Bridge Replacement
- Nuclear Fuel Canister Storage Building
- SR 16, Sprague to Snake Lake
- Meydenbauer Bridge Replacement
- I-5, 2nd St. Bridge
- SR 16, Union to Jackson
- York Bridge Superstructure
- Seattle Freeway Park
- Seattle Westlake Park
- Weller Street Elevated Pedestrian Walkway
- Eastgate Transit Access
- Seatac South 160th St. Loop
- Oregon
- Idaho
- Nevada
- Alaska
Mowat Construction Company Capabilities: Piling Foundations
SR 900, Newport Way to I-90 Widening
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| Client/Owner: | Washington State Department of Transportation |
| Location: | Issaquah, WA |
| Cost: | $12,200,000 (Total Contract Value) |
This project significantly widened ¾ mile of SR 900, adding turn, bus and HOV lanes. The project also included widening the I-90 overpass. SR 900 runs through an area of extensive wetlands which feed the Issaquah Creek salmon habitat, limiting room for roadway widening. To maximize the roadway width, pedestrian boardwalks on timber piling were constructed in lieu of sidewalks. Retaining walls were used to minimize encroachment on the wetlands by roadway fill. Four different pile driving activities were performed:
- Timber pile for boardwalks – 490 each, 25 to 48 feet long supported 2,940 LF of boardwalk
- Soldier pile for retaining wall – 95 each, W12x65 and W12x120, 46 to 49 feet long
- Sheet pile for temporary shoring
- Cased pile for bridge foundations – 68 each, 24” steel pile filled with reinforced concrete, 103 to 138 feet long