In March 1951, the Washington Legislature raises the speed limit on the state's highways to 60 miles per hour, despite a highway department survey showing that not a single highway in the western part of the state was safe at that speed.
Most of the state's highways had been designed for vehicles that were smaller and slower than those on the roads by the early 1950s. Accident rates had risen as the volume and speed of traffic increased. Rates decreased during World War II, when the speed limit was reduced to 35 mph as a conservation measure, but rose again when the previous limit of 50 mph was restored at the end of the war in 1945.
After the war, the highway department began pressing for access controls as a way of improving highway safety. This approach had been used successfully in several other states. Vehicles entering or leaving the traffic stream created hazards on narrow but high-speed roadways. In 1945, state highway engineers began trying to convert the Pacific Highway between Tacoma and Everett (then the most heavily traveled highway in the state) to a four-lane limited access highway. However, the Legislature curtailed this effort two years later when it passed a bill authorizing the department to restrict access only on new routes, not on existing roads.
In 1951, at the same time it raised the speed limit to 60 mph, the Legislature finally gave the highway department the authority to use access controls as a way of upgrading existing highways to meet modern safety standards.
