 Local residents created the Colfax Highway Association in 1967 at the Peardale firehouse , about halfway between the two ends , in order to preserve the rural nature of the road . When the 21 @-@ foot ( 6 @.@ 5 m ) wide 1924 concrete arch bridge that took SR 174 across the Bear River on the county line was set for replacement in the late 1980s , the group successfully lobbied to preserve it for non @-@ motorized traffic . The association also pushed for Nevada County 's Gold Country Stage bus service to add a route along the highway to Colfax , which was agreed to in late 1998 and still runs as Route 12 , connecting downtown Grass Valley with Colfax 's Amtrak station . After a request by Nevada County in 1988 , the state legislature designated the part of SR 174 in unincorporated Nevada County ( between the county line and the Grass Valley city limits ) as eligible for the State Scenic Highway System in 1991 . In 1999 , the Colfax Highway Association attempted to get the route officially declared a State Scenic Highway . They argued that the designation would " protect the scenic character and rural flavor of the highway " . A newly formed group , Concerned Citizens for 174 , opposed the designation because it would restrict the property rights of residents along the highway , for instance requiring them to use " natural colors " . The opposition was successful , and SR 174 remains eligible for State Scenic Highway status but is not a State Scenic Highway . 
