To date, 740 pre-cast concrete girders have been installed to form the superstructure of the Hanford Viaduct. Between Grangeville and the San Joaquin Valley Railroad, crews will begin to work on the parapet walls later this spring. Further south on Lacey Boulevard, crews are working on the columns needed to extend the viaduct over the highway. Earlier this spring, crews were seen placing concrete to form columns in the median of the highway. In the coming weeks, crews will work at night to place the first pre-cast concrete girders over the highway. The Hanford Viaduct is the largest high-speed rail structure currently underway spanning 6,330 feet long.