The P&L Railroad bridge relocation allows for construction of a new longer lock at Kentucky Lock and Dam at the site of the existing bridge. The new lock and bridge will make river navigation in the future easier for barges.

Tetra Tech INCA provided design and construction services for the bridge relocation. INCA’s work consisted of providing foundation design for a 3,500-foot long, 15-span bridge structure spanning the Tennessee River. INCA’s services on this project included:

Work included the design of 11 piers, each of which included 4 drilled shafts, a 34-foot diameter shaft cap, a 10-foot diameter column, and a column cap. Drilled shaft lengths ranged from 75 to 105 feet, and are embedded in bedrock with rock socket depths varying from 25 to 42 feet. Pier heights (above the shafts) range from 72 to 82 feet.

The Louisville District is constructing a new lock and dam on the Ohio River at Olmsted. Tetra Tech INCA was responsible for preliminary and final design of the new lock approach walls, which will guide barge traffic and other marine vessels into and out of the new twin lock chambers in a more efficient manner. The approach walls are a component of the overall project design for the replacement of the two old locks at Dam No. 52 and Dam No. 53. The project will feature two 110-foot by 1,200-foot locks, a spillway section controlled by five tainter gates, a navigable pass, and a fixed weir section. Upon successful completion of the project, the waiting time in the locks will be decreased by half, while river traffic will be dramatically increased.

INCA developed this innovative design concept and prepared the final plans, specifications, and cost estimates for 4,000-linear feet of post-tensioned concrete pontoon floating approach walls and 600 feet of fixed approach walls. In addition to the structural analysis and design, INCA was responsible for providing electrical engineering, including power distribution, high-mast lighting, CCTV system, communication systems, pumping systems, and navigation lighting. The design accounts for impacts with a 15-barge tow that carries 60 million pounds of cargo and redirects this traffic into the lock chambers. Because the facilities are located in Seismic Zone III, the anchor pylons and nose piers required seismic analysis, including pseudostatic, response spectrum, ground motion determination, and time history.

Serving Seattle’s north end residents, this King County Metro transit hub has provisions for serving the traveling public with both bus and future light rail. INCA Engineers was selected, as the prime consultant, to provide a multidisciplinary team of specialists to design Metro’s Northgate Transit Center.
   
INCA developed a design report that identified preliminary alternatives and associated costs utilizing the technical knowledge gained from years of design and construction experience with transit and park-and-ride facilities, input from Metro, local communities, and businesses. The alternative selected from the design report consisted of a transit station and 300-stall park-and-ride lot, with the option for a future 1,200-stall parking garage. The selected alternative also allowed for the facility to be utilized as a light rail/regional transit station. Key design areas included identifying geometric design criteria, access for both buses and vehicles on and off the site, lot layout, internal circulation, street improvements, pavement evaluation, regional storm drainage detention/outfall including design of flow restrictors and oil pollution control devices, and safe ADA/pedestrian facilities.

Designed for use by both light rail and buses, the Northgate Transit Center easily fits in with Puget Sound’s Regional Transit System Plan.

Tetra Tech INCA provided a variety of survey and mapping services for the design of the proposed North SeaTac Park. The 260-acre site encompasses residential neighborhoods vacated as part of the Airport’s noise reduction program, and is scheduled to be developed as a multi-use complex of trails, playfields, community center, tennis courts, and open space. In addition, INCA provided the client with transportation support services, including traffic data used to establish existing arterial traffic conditions, and estimates of traffic volumes that would be generated by park activities.

Tetra Tech INCA provided engineering services for the development and implementation of the City of Shoreline’s Neighborhood Traffic Safety Program (NTSP). The project included consensus building within a technical advisory committee which included city engineers and maintenance personnel, emergency response personnel, neighborhood representatives, the general public, and city council members. INCA prepared the NTSP document and assisted the City with program implementation by coordinating neighborhood speed and volume counts, attending and facilitating neighborhood meetings, and preparing individual neighborhood Residential Area Plans (RAP). Upon completion of each RAP, INCA completed an engineering analysis resulting in recommendations for slowing traffic, and reducing accidents and traffic volumes.