Transportation and Roadway Projects
Transportation and Roadway
A significant portion of our experience has been dedicated to transportation related development for design and review. Our projects span signal systems, transit facilities, airports, urban and rural roadway reconstruction as well as rehabilitation. SCE is current and well versed with state and local agency standards, viable LID methods, AASHTO and Federal Transit Authority (FTA).
transportation and roadway projects
First Hill Streetcar
SCE was commissioned to assist in the completion of the Seattle Street Car system, which connects the residential neighborhoods and business districts of Capitol Hill, First Hill, Yesler Terrace, Central Area, Chinatown-International District and Pioneer Square, while also providing transit service to Swedish Medical Center and Harborview Medical Center, colleges such as Seattle Central College and Seattle University and sporting event venues (CenturyLink and Safeco Field). SCE provided design and supplemental topographical survey verifications for the design of: SCL 13.8kv duct bank replacement; pavement restoration; ADA adjustments; and site foundation design for the traction power substations.
Sound Transit Northlink N125 from UW to Northgate, Seattle WA
SCE is assisting Sound Transit with its Northgate Link Extension project, which will connect the Northgate, Roosevelt and U District neighborhoods to downtown Seattle and the airport. Fast, reliable service will provide relief to one of the region’s most congested traffic areas.
SR99 Bored Tunnel Project and AWV Replacement – Seattle, WA
The SR99 Bored Tunnel Project replaced the Central Waterfront Section of the Alaskan Way Viaduct. As team members to the STP-JV general contractor, SCE served as the utility civil/structural engineer. This project was a fast track Design-Build. SCE performed the engineering design, supporting the contractor to relocate the Seattle City Light (SCL) 115kv, 26kv, and the 13.8kv network services, water main design for temporary relocation, PSE and other utility temporary or permanent relocations to clear the way for the excavation of the open cut and bored tunnel, at both north and south portals. This effort required close collaboration with the utility contractor, SCL, WSDOT, and SDOT as is typical with Design-Build projects. There were significant de-construction and reconstruction elements to this project requiring special attention to phasing of the work. Construction began in March 2012 and completed in 2018. SCE also supported the settlement monitoring of the excavation and tunneling of this project as a sub-consultant to Sol-Data Incorporated, an expert construction deformation monitoring firm with strong international experience. SCE performed the professional field surveying; providing vertical and horizontal control, the field survey monitoring and engineering services throughout the excavation and boring of the tunnel for the duration of the project.
SCE was part of the design team with Parsons and we prepared the utility monitoring program along this phased-construction project along the Seattle waterfront. The challenges were the tight settlement tolerances allowed on the existing Seattle City Light High Voltage underground circuits and vaults, and the structurally sensitive Alaskan Way viaduct adjacent to the excavation. As part of the deformation monitoring program a combination of systems were utilized including automated optical observations, inclinometers, extensometers, piezometers, and manual surveying in frequency readings to ensure real time, hourly and daily condition reporting.
SR 305 Widening
SCE provided the engineering design for the City of Bainbridge Island (COBI) to complete a widening of the shoulder of SR305. Services rendered include a topographical survey, widening of the east shoulder of SR305 from Vineyard Lane to High School Road to complete a non-motorized corridor to the ferry terminal and Winslow Way, and revisions to the existing traffic island at Vineyard Lane. SCE also re-graded the ditch and prepared drawings to WSDOT Standards, revised roadside safety elements, and re-striped the road at the traffic island.