Except as may be provided by rules and regulations adopted under RCW 47.28.030
as now or hereafter amended the department of transportation shall publish a call for bids for the construction of the highway according to the maps, plans, and specifications, once a week for at least two consecutive weeks, next preceding the day set for receiving and opening the bids, in not less than one trade paper of general circulation in the state. The call shall state the time, place, and date for receiving and opening the bids, give a brief description of the location and extent of the work, and contain such special provisions or specifications as the department deems necessary. When necessary to implement chapter 39.19
RCW and the rules adopted to implement that chapter, the department shall include in its call for bids provisions or specifications requiring bidders to comply with chapter 39.19
RCW and the rules adopted to implement it: PROVIDED, That when the estimated cost of any contract to be awarded is less than fifty thousand dollars, the call for bids need only be published in at least one paper of general circulation in the county where the major part of the work is to be performed: PROVIDED FURTHER, That when the estimated cost of a contract to be awarded is seven thousand five hundred dollars or less, including the cost of materials, supplies, engineering, and equipment, the department of transportation need not publish a call for bids: PROVIDED FURTHER, That after a bid call has been advertised for two consecutive weeks it may be postponed and the bids opened one week later.