A plan to install a roundabout at the Hilo Bayfront moved one step forward Friday despite reservations from residents.
In an effort to improve traffic flow at the north edge of Downtown Hilo, the state Department of Transportation intends to convert the intersection of Waianuenue Avenue, Kamehameha Avenue and Bayfront Highway into a single-lane roundabout.
In addition to the traffic benefits, the project is also intended to improve nearby pedestrian and cyclist infrastructure in conjunction with the County of Hawaii’s Downtown Hilo Multimodal Master Plan, which was developed in 2017 and called for broad accommodations to improve the walkability of Downtown Hilo, including several roundabouts.
The full project is estimated to cost about $18.5 million.
A final environmental assessment for that project was published Friday in the state’s Environmental Notice, revealing few changes to the proposal’s scope, but also skepticism from community members who commented on a draft assessment earlier this year.
As presented in the assessment, the project would be carried out in five phases over the course of two years, with construction estimated to begin in 2025.
These phases would gradually build out the roundabout, which would connect five roads: Waianuenue Avenue, east- and westbound Kamehameha Avenue, Bayfront Highway and Highway 19.
Three of those phases would entail only minimal disruptions to traffic, with the assessment stating that all currently permitted turns will be possible during those phases, but may be shifted to different parts of the roadway using cones or barricades.
The first phase, during which the Bayfront and Kamehameha legs of the roundabout would be built, along with reinforcements to the nearby seawall, would reroute traffic just around the immediate construction area.
Phase two, which would install traffic islands between Bayfront Highway and Kamehameha Avenue, would do the same.
During phase three, however, the entire stretch of Waianuenue Avenue between Kamehameha Avenue and Keawe Street would be completely closed to traffic while the leg connecting that road to the roundabout is built.
Traffic would be detoured through adjacent streets, but the assessment states that this closure would make the third phase the shortest.
Phase four would build out the Bayfront Highway approach to the Wailuku River Bridge — requiring partial closure of the highway’s southbound lane — while phase five would build out the center of the roundabout and surrounding traffic islands, which would, like the first two phases, only require immediate rerouting around the construction site.
Public comments published with the assessment Friday expressed concerns with the impacts to traffic circulation both during and after construction, with several community members questioning whether the project will actually improve traffic at all.
“I have found that the existing traffic signals regulate traffic through the intersection in a perfectly acceptable manner,” wrote resident Helie Rock. “The only time there has been unacceptable traffic congestion has been during the recent repair work on the Wailuku River Bridge.”
Rock wrote that, because the majority of traffic through the existing intersection is passing from Bayfront Highway to Highway 19 or vice-versa — traffic studies in the assessment estimate only 30% of traffic from Hamakua turns off of the highway at the intersection — more traffic will be “needlessly directed out of their way around the circle.”
Rock suggested that the DOT’s plans for improved traffic flow and pedestrian access can be achieved with much less disruption — and at less cost — than the roundabout plan.
Nikiya White, a Mountain View resident, wrote that the roundabouts installed at Ainaloa and Pahoa have not particularly improved the traffic problems along Highway 130.
Indeed, she wrote, the Ainaloa roundabout “causes traffic to completely back up” due to its small circumference, something she feared would happen again with the Hilo project.
Meanwhile, a statement by the nearby Connections Charter School noted that the project will severely impact families dropping off and picking up students: exit routes to the school’s parking lot, parking stalls on Kamehameha Avenue, bus parking spaces and an access route to the school on Kalakaua Street would all be cut off by the project without any obvious replacements.
In response, the assessment states that, while there will be temporary impacts to those features during construction, alternative routes will be provided, and enough notice will be given in advance for users to adapt.
In addition, once the project is completed, conditions at the school should return to their present state.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.