The road along Cold Creek was closed in November 1943 as part of the establishment of a federal weapons development facility at the Hanford Site during World War II. To serve the new facility and evacuate residents in the event of an emergency, a four-lane highway bypassing Richland to the west was constructed by the county government in July 1948, connecting to US 410 with a new bridge over the Yakima River that was built by the Atomic Energy Commission. The remaining stretch of US 410 was moved to an expressway connecting with the new Pioneer Memorial Bridge, which opened on July 30, 1954.