To meet current engineering standards and improve riparian and aquatic habitat, Aspect is providing geotechnical services for the replacement of a levee and river revetment for a 1.4 mile length of the Lower Russell Road flood protection system along the east bank of the Green River in the City of Kent. The project will improve flood protection for the residents and businesses of Kent, Tukwila, Renton and the Green River valley. Aspect Consulting is the lead geotechnical engineer for the project. They completed field investigations to characterize the subsurface conditions in support of the design and construction of the new levees and ecosystem restoration features. Aspect is completing seepage and slope stability analyses for levee design, and providing geotechnical recommendations for levee embankment material, roads, utilities, and habitat features. The project objectives include designing a system that minimizes long-term maintenance needs and associated costs, and balancing policy directives regarding flood protection (e.g. scour protection, stability and vegetation maintenance), habitat restoration, and recreational use.
Aspect provided geotechnical design for a pile system for a new utility bridge to help restore hydraulic continuity and the marine estuary. Key project challenges included pile design within the site's soft marine sediments and re-routing utilities beneath the estuary using directional drilling technology. The project involved collaboration with several stakeholders including the Jamestown S’Klallam Tribe, project engineer, contractor, and private land owner. Aspect also provided written specifications for the foundation components of the project and construction support.
Aspect is providing geotechnical and environmental services for estuary rehabilitation and traffic congestion relief where existing twin 72-inch culverts will be replaced by a new bridge. The project includes rehabilitating the Clear Creek estuary and widening the existing two-lane road. The culverts will be replaced by a four-lane bridge along NW Bucklin Hill Road at the Clear Creek crossing to relieve traffic congestion and restore pre-existing estuary conditions. Aspect is providing design recommendations in accordance with WSDOT Local Agency Guidelines and LRFD methodology.