Nampa SH-45 Elijah Drain Culvert Repair Restarts on 12th Avenue

NAMPA — Repairs to the Elijah Drain culvert beneath State Highway 45 (12th Avenue) near West Dewey Avenue in Nampa, Idaho, are back underway. The Idaho Transportation Department (ITD) announced Nov. 6, 2026 that it is restarting the SH-45 culvert project, which addresses deterioration in the culvert that carries the Elijah Drain under the highway.

Why the SH-45 culvert work paused

ITD said work was temporarily paused after crews uncovered underground utilities in locations that differed from the project plans. Those unexpected conditions required changes to the planned work before crews could continue.

According to ITD, the repairs will protect the roadway and the people who use it by addressing the deteriorating culvert beneath the highway. Construction is expected to be completed next spring.

Overnight lane cuts on 12th Avenue

Crews are locating underground utilities overnight Nov. 10-12. Each night, SH-45 is reduced to one lane in each direction from 10 p.m. to 5 a.m. the following morning, ITD said.

Drivers should expect more lane closures and traffic shifts as construction continues through spring. SH-45 will remain open, and access to all local businesses along 12th Avenue will be maintained. ITD asks drivers to slow down, watch for crews and follow posted signs. Current traffic information is available at 511.idaho.gov. CBS2 also reported on the shifting closures.

Getting around south Nampa

12th Avenue is one of Nampa's main north-south routes, and several other road projects are in the works nearby, including the Robinson Road railroad overpass. See the Nampa city guide, browse new home communities in Nampa like Adams Ridge and Bentley Meadows, check homes for sale in Nampa, or read more Nampa growth news. Thank you for reading Treasure Idaho.