 On March 22, 2014, a three-mile section of SR 530 in northern Snohomish County, roughly midway between Darrington and Arlington, was completely blocked by the Oso landslide.The highway was cleared enough by May 31 to open one lane of escorted traffic and by June 20 to two-lane traffic.Temporary access had been restored within a month of the mudslide using a utilities road guided by pilot cars.