TRANSPORTATION AND ROADWAY PROJECTS

TRANSPORTATION AND ROADWAY PROJECTS

TRANSPORTATION AND ROADWAY

SCE has past and ongoing projects related to transportation development. With experience gained from WSDOT, SDOT and Sound Transit, SCE has and continues to be responsible for design and design services during construction on multiple roadway and light rail projects. Aspects covered include signal systems, transit facilities, airport, urban and rural roadway construction projects. SCE  works with state and local municipalities and is well versed with applicable standards, viable LID methods, AASHTO and Federal Transit Authority (FTA).

PUGET SOUND GATEWAY PROJECT | SR 509, I-5 to 24th AVENUE S - NEW EXPRESSWAY PROJECT, PHASE 1B

The Project provides an alternate to the I-5 through Seattle, reducing traffic congestion, connect freight links and an alternate access to Seatac airport.

The Project covers construction of SR 509 from I-5 to 24th Avenue S., including the interchange with I-5. On I-5, the Project constructs improvements along approximately 2.5 miles from S. 200th Street to SR 516.

SCE is the engineer of records for various aspects including: noise walls, retaining walls (MSE and Soil Nailed), monotube steel structures (both WSDOT standard and non-standard) and foundations as well as waterline relocation designs.

Water Main relocation of existing watermains crossing the route of the road, from 8″ to 30″ diameter. Special blocking requirements were designed to restrain the waterlines as required due to ground conditions. Removal of watermains no longer in service was also coordinated.

PORT OF SEATTLE TERMINAL SECURITY ENHANCEMENTS PHASE II BOLLARDS

SCE successfully completed design services for the installation of structural bollards for accessing the terminal from the airport drives, parking garage and accessible curbside ramps at the arrival and departure levels. The effort required the development of up to three design alternatives and a final design for the sidewalk architectural finish at the arrivals drive, departures drive, shuttle bus pick up drive and skybridge pedestrian access that also included MOT.

The resurfacing, installation of bollards, and the replacement of 41 ADA curb ramps required special consideration since they occurred primarily over existing reinforced elevated concrete structures at the arrival and departures areas. A detailed analysis of the existing structural as-builts of the airport was necessary to determine where there were existing topping slabs that could be demolished to install the bollard foundations and reconstruct the pedestrian surfacing. At departures level we were able to remove the 6-inch topping slab over the structure which permitted the demolition and rebuild with the integral shallow bollard foundation and pour a new ADA landing and ramps. At the arrivals level, the structure did not have a topping slab which only allowed us to mill ¼-inch on the structure for resurfacing. We developed a solution for this problem by taking the drop-off lane adjacent to the existing curb to install the bollards and its foundations, bringing the vehicle travel lane asphalt flush to the new curb line and adding half-dome tactile strip along the entire length of the new pedestrian and vehicular interface.

I-405 BUS RAPID TRANSIT, EXPRESS LANES, RENTON TO BELLEVUE D-B

The Renton to Bellevue project is designed to reduce congestion and improve safety performance along one of the state’s most congested sections of highway.

The project will add new capacity to create a two-lane express toll lane system between SR 167 in Renton and Northeast 6th Street in Bellevue. In general, the project will add one new lane in each direction. The existing HOV lane will be combined with this new lane to create a dual express toll lane system.

SCE was the utility design consultant for this $705M design build project. We designed or organized utility relocations that included City of Bellevue, Renton, Coal Creek UD, KCWW and SPU water and sewer lines. These involved multiple size sewer and water systems, some of which required encasement under the freeway, on or under proposed bridges and wall structures. We also assisted in the coordination of all affected utility owners including PSE power and gas for the franchised relocations.

SR 99 BORED TUNNEL PROJECT

SCE supported STP-JV with design and surveying services for this 2.2-mile tunnel project. SCE had four contracts:

  1. Design of the utility relocation and street restoration work;
  2. Utility monitoring QA;
  3. Manual survey for the settlement monitoring program;
  4. QA Structural and Material Controls inspection.

SCE served as the utility civil/structural engineer to relocate the Seattle City Light (SCL) 115kv, 26kv, and the 13.8kv electrical circuits, SPU’s water main relocations, SPU’s AWS 24” temporary CSO re-route and lift station during the TBM rescue operation, PSE and other utility relocations to clear the way for the excavation of the open-cut and bored tunnel, at both north and south portals.

Our team designed the supports for the critical relocation of the 115 KVa main service loop from the Massachusetts to the Union Substation along the waterfront. The design was to support this critical infrastructure for the 4-year duration of the tunnel boring and utility project in support of HNTB and the Design-Build team. This design required our team to design for crossing seismic expansion joints, anchoring into the 1960’s elevated SR 99 structure, and provide a design that included an elevated level of seismic and safety importance factors to safely support this critical infrastructure. Our design included the supports and safety shrouds to protect cars and the public from this high voltage power line.

Due to the nature of a DB project, there was little time from the design documents phase to construction and regularly due to unforeseen field conditions re-designs and field adjustments were necessary to complete the work. Our understanding of DB approach allowed us to be successful in our 7 years of involvement.

ALASKA WAY VIADUCT DEMOLITION

SCE completed the pre- and post- demolition building assessments for the structures that fell within the limits for demolition activities along the Alaska Way Viaduct.  

Professional neighborhood interaction was critical to help promote community tolerance of the neighborhood disruption and encourage right of entry cooperation.

SR 305 FERRY TO HOSTMARK SAFETY IMPROVEMENTS

A suite of improvements along the SR 305 corridor including multiple roundabouts and intersection modifications. The proposed improvements represent an incremental approach to improve mobility. This approach maximizes the capacity of current infrastructure.

SCE supported WSDOT with the utility as-built surveys and relocation design for this 12-mile corridor that includes six roundabouts and five intersection modifications. The more significant utilities affected by these improvements are PSE distribution and franchise communication systems, some of which required undergrounding to accommodate the widenings and adjustments.

 

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 included 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 to otherwise minimize significant earthworks and prepared drawings to WSDOT Standards, revised roadside safety elements, and re-striped the road at the traffic island.

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. 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.

SEATTLE SEAWALL

SCE was part of the design team with Parsons Corp. 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.