County signs cooperative agreement with ITD for new signal at Highway 48/4000 and approves engineering contract

Jefferson County commissioners approved a three-party cooperative agreement with the Idaho Transportation Department (ITD) and the City of Rigby to install a traffic signal at the intersection of State Highway 48 and 4000 East.

County staff described an ITD cost-share arrangement covering up to $500,000 for the signal installation. The cooperative agreement sets responsibilities for construction, pedestal excavation and future maintenance; the state will provide half of installation costs and split ongoing maintenance with the county and the city.

Commissioners also authorized an engineering contract with Civil Science to produce the required engineering drawings and specifications so the project can be put out to bid. Civil Science proposed converting existing design work (a prior signal plan used at another intersection) and verifying it in the field; staff reported the firm could complete the engineering within about four weeks for an estimated $17,000–$20,000.

Commissioners moved to approve the cooperative agreement and, separately, to contract Civil Science to prepare the signal plans. Both motions passed on roll-call votes. County staff said Civil Science would begin immediately so the county can seek contractor bids and coordinate with the City of Rigby on excavation and utility work.

County leaders characterized the project as critical to traffic safety and to reducing congestion near the highway/railroad overpass; staff said the state had approved the funding ceiling and that a local contribution will be documented in the cooperative agreement.