A project to build a traffic roundabout in downtown Hilo has received more than $17 million in federal funding.
U.S. Sen. Brian Schatz announced Monday that the state will receive more than $42.5 million from the U.S. Department of Transportation to support infrastructure improvements in Hilo and Honolulu.
Included in that appropriation is a $17.5 million grant to reconfigure the intersection of Hilo Bayfront Highway, Kamehameha Avenue and Waianuenue Avenue into a single-lane traffic circle.
The project, as summarized in an environmental assessment published last year, is necessary to address consistent traffic congestion at the intersection, which is exacerbated on the frequent occasions when Bayfront Highway is closed due to flooding or high surf.
In a press statement announcing the funding, Schatz also highlighted three collisions at the intersection and one death of a cyclist in the last two years. Law enforcement attributed the fatality to a lack of bicyclist infrastructure in the area.
The federal DOT funding, awarded through a Rebuilding American Infrastructure with Sustainability and Equity grant, would not only create a roundabout joining five roads, but would make additional roadway modifications, including parking reconfigurations, new signage, pedestrian signals, ADA-compliant sidewalks and road crossings, drainage improvements and more.
State DOT spokeswoman Shelly Kunishige said the federal funding accounts for only 80% of the total project cost, which is estimated at about $22 million. The state will cover the difference.
Kunishige said the project design was about 30% completed as of March, and predicted that it could be completed by mid-2025, after which construction could begin by mid-2026. Construction is estimated to take two years to complete.
“For roundabouts, we generally build them one side at a time so the intersection could remain open in some capacity throughout the construction,” said Kunishige in an email.
According to the environmental assessment, the project will be carried out in five phases: first building the Bayfront and Kamehameha legs of the roundabout, then installing traffic islands between Bayfront and Kamehameha in phase two, and then building the Waianuenue leg of the roundabout in phase three.
Phase four will build out the stretch of Bayfront Highway as it approaches the Wailuku River Bridge, and the final phase would build the roundabout center and surrounding traffic islands.
Kunishige said further details about the construction process are still undetermined, pending the completed design and negotiations with contractors.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.