Lakewood Interceptor

Marysville, Washington

HWA performed engineering studies to evaluate subsurface conditions and provided recommendations for design and construction of the geotechnical aspects of the Lakewood Interceptor Project in Marysville, Washington.

Geotechnical studies were first performed along a 12,000-foot preliminary alignment that was generally parallel to the BNSF tracks from 19th Drive NE to 140th Street at Smokey Point Boulevard. Subsequently, a new route was selected that generally followed Twin Lakes Avenue. The preferred alignment included construction of approximately 9500 lineal feet of 30 and 24-inch diameter, 15-foot deep, gravity sewer line and associated manholes. The project included three bore-and-jack under-crossings.

Schedule A work on the project included the140th Street NE bore-and-jack crossing of Interstate 5 (I-5) and the Burlington Northern Santa Fe (BNSF) Railroad mainline tracks. This crossing consisted of approximately 550 linear feet of 24-inch sewer pipe and an 18-inch water main.

Schedule B included a 450-foot long bore-and-jack crossing of I-5 at 148th Street NE for a 30-inch diameter sewer pipe. The entire project alignment was underlain by highly permeable sand and gravels, and the ground water level was within 2 or 3 feet of the ground surface. In addition, HWA provided construction monitoring services.

HWA received a Gold Award in Exceeding Client / Owner Needs at the American Council of Engineering Companies (ACEC) of Washington's 2007 Engineering Excellence Awards.