Longmont reaps benefits of $25 million RAISE grant for Diagonal Highway

Technically, Boulder County was the recipient of a $25 million Rebuilding American Infrastructure with Sustainability and Equity RAISE grant to fund safety and mobility improvements along Diagonal Highway.

But Longmont officials say it was a collaborative effort between several government agencies that will greatly benefit the city, too.

In addition to Boulder County, the cities of Boulder and Longmont as well as RTD and CDOT had a helping hand in securing the federal grant.

“We all worked on this together for all iterations of the grant,” Phil Greenwald, Longmont transportation planning manager, said in an interview Thursday. “It’s always been a group effort, it’s just whose name was on the front.”

Approximately $15 million from the grant will go toward improvements at the Hover Street and Diagonal Highway intersection. Those updates will include separate underpasses for Boulder-bound automobiles and bicyclists and pedestrians. There will also be intersection improvements for more efficient bus access, Greenwald said.

Roughly $10 million of the RAISE grant will go toward improvements at Colo. 52 and Diagonal Highway intersection.

“This grant goes to… a bunch of different places,” Greenwald said. “It just fills in all the gaps that we’ve had in this project.”

The grant dollars were very competitive, as the federal RAISE program received $15 billion worth of requests but only had a budget of $2.2 billion this year.

“This grant will help to accommodate our state’s growing population as we work to develop a safer, more reliable transportation corridor between two of the fastest growing cities in Colorado: Boulder and Longmont,” Rep. Joe Neguse, D-Colo., said in a news release.

The Colo. 119 Diagonal Highway Mobility Improvement Project will utilize innovative technology such as adaptive signal controls and AI cameras to monitor pedestrian and bicycle usage, according to the U.S. Department of Transportation.

CDOT will manage the project in collaboration with Boulder County and various municipal governments including Longmont.

Public outreach and design for the project will continue through 2024 with construction scheduled to follow in 2025 and beyond.

On average, approximately 45,000 vehicles travel along Diagonal Highway daily, according to CDOT data.

Traffic volume along Diagonal Highway is also expected to increase 25% by 2040.