Drivers who use the Interstate 10 “Deck Park Tunnel” north of downtown Phoenix this spring will likely notice improvements in the lights used to illuminate the 30-year-old structure.

The Arizona Department of Transportation started a $1.4 million project to add a modern LED lighting system in the I-10 tunnel in January. In all, crews are scheduled to change out more than 3,200 individual lights inside the I-10 tunnel during overnight closures over the next few months. 

As with the current system, the improved LED tunnel lights will be set at appropriate transitioning levels during daylight and nighttime hours to allow a driver’s vision to adapt given outside lighting levels. For example, the system will run fewer lights at night because of lower nighttime light levels outside the tunnel.

In addition to being a safety enhancement, ADOT anticipates the use of LED lights in the tunnel will produce more than $175,000 in annual energy savings.

So far, more than 450 energy efficient LED fixtures have replaced original light fixtures on the ceiling of the westbound I-10 side of the tunnel. The LED system will provide improved lighting levels inside the tunnel, which extends approximately three-quarters-of-a-mile between Third Street and Third Avenue. 

Closures for lighting installation currently are scheduled on Friday nights. The next closure is planned along eastbound I-10 between the I-17 “Stack” interchange and Seventh Street from 9 p.m. Friday, Feb. 26, to 9 a.m. Saturday, Feb. 27.

The LED lights are replacing a high-pressure sodium lighting system that has been in use since the Deck Park Tunnel opened in August 1990.

The tunnel lighting project is being paid for with ADOT maintenance funds.