 In the 1980s the highway 's flood resistance was improved with the construction of new , higher @-@ level bridges to replace lower crossing . Galena Bridge over the Murchison River opened on 9 December 1983 , and a new bridge over the Harding River near Roeburn was opened on 22 March 1985 . In the late 1980s the various sections of road across Western Australia 's road network were upgraded or reconstructed , with the worst segments prioritised . In August 1988 , work on upgrading five and a half kilometres ( 3 @.@ 4 mi ) of North West Coastal Highway was completed , the final section between Geraldton and Carnarvon to have been brought up to standard . In the following two years , segments with a combined length of 241 kilometres ( 150 mi ) were resealed , and 45 kilometres ( 28 mi ) was widened from 6 @.@ 2 to 7 metres ( 20 to 23 ft ) , with a one @-@ metre @-@ wide ( 3 @.@ 3 ft ) sealed shoulder on each side . 
