• Project

US 97A Illumination and Signal Cabinet Update - Complete September 2025

Project overview

This project has replaced the existing, failing, illumination system inside the Knapps Hill Tunnel. This project is also part of a larger endeavor that fixed and replaced signal cabinets in Leavenworth and parts of Grant County, both of which have already been completed.
In addition to the lights themselves, the project has replaced all their conduits and wiring, as well as the structures installed to support them.
The new lighting system is more modern and has allowed for a variety of functions based on ambient light, as well as provide a backup system in case of blackouts.
Not replacing the lights would have resulted in hazardous driving conditions with low visibility for the users of the tunnel.

Timeline
September 2025
Project status
Completed
Funding
$680,000

What to expect

The Knapps Hill Tunnel  closed for the duration of the project (about three weeks), which began after Labor Day on Sept. 8 and lasted until Sept. 24, to reduce the amount of traffic affected. Detours  were placed around the tunnel at SR 971 and US 97. Neither detour had a weight restriction. 

This project came about  as a result of the failure of several lights inside the tunnel. The need to replace them, coupled with the need to update the signal cabinet resulted in the three-week project. There was an extraordinary need to carry this out, given the failing lights and the need to keep the tunnel safe in an area that sees heavy traffic during tourist seasons.