Complex sentence: SR 527 became a state highway during the 1964 highway renumbering, in which the Washington State Department of Transportation (WSDOT) replaced the previous system of Primary and Secondary Highways with a new system called State Routes, which is still in use today.
Split into simpler sentences: SR 527 became a state highway during the 1964 highway renumbering. During this time, the Washington State Department of Transportation (WSDOT) replaced the previous system of Primary and Secondary Highways with a new system called State Routes, which is still in use today.