Grading, Drainage, and Pavement Challenges Associated with Development of Pierce County Terminal

Abstract

The Pierce County Terminal project redevelops an existing general cargo, automobile marshalling facility, and warehousing area into a new container terminal. The terminal consists of a truck entrance and chassis storage area, a main container yard, an intermodal rail yard, and ship berth. Redeveloping the existing mixed use terminal into a container terminal presents several challenges for the design of grading, drainage, and pavement systems. Each of these systems are interrelated and cannot be designed separately. Grading of the site has an impact on the terminal operation. Grades should be minimized to the extent practical, and it is important to minimize abrupt grade changes, particularly within the container stacks. Drainage design also has an impact on terminal operations. Sufficient drainage structures must be provided to minimize ponding, and proper placement of drainage structures is necessary to avoid impacting operations. As with most container terminal developments, the pavement is a primary cost component of the overall project development. Several design considerations play an important role in selecting the most appropriate pavement type for the terminal. These include subgrade conditions, wheel loads due to container handling equipment, anticipated wheel load repetitions, pavement properties, local practices and experience, required operational flexibility, and of course, cost. This paper will discuss some of the challenges faced by the designers to evaluate and design the grading, drainage, and pavement systems at Pierce County Terminal to accomplish operational and cost goals of the project.