The state is moving forward with a $15 million project to replace the 90-year-old Waiaka Bridge in Waimea.
The project, which also includes realigning Kawaihae and Kohala Mountain roads and installing a roundabout at their intersection, is expected to be complete by the end of 2024, should construction get underway as planned in summer 2023.
A final environmental assessment, which anticipates a finding of no significant impact for the project, was published Friday, allowing the project to move forward.
“The build alternative selected in the Final EA will improve safety and reliability for users of the route connecting Waimea, South Kohala, and the coast and will facilitate the transportation of goods and services to Kawaihae Harbor,” said Department of Transporation Spokeswoman Shelly Kunishige. “The roundabout planned for the Kawaihae Road and Kohala Mountain Road intersection will increase line of sight and allow for improved traffic operations.”
While the use of Federal Highway Administration funding typically triggers compliance with the National Environmental Policy Act review process, an environmental impact statement is not needed under “Categorical Exclusion” the state determined.
The $15 million price tag for the project would be shared between the state and federal governments, with the state kicking in 20% of the cost and the feds 80%. Replacing Waiaka Bridge is considered a “system preservation project” on the Statewide Transportation Improvement Program list for fiscal years 2022-25 making it qualified for federal funding. State funding for the project was included in the 2022-23 CIP budget passed this year.
“We will be using our federal formula funds authorized under the Infrastructure Investment and Jobs Act for the federal funding,” Kunishige said.
Earlier this year, when the draft EA was released, the project was estimated at $10 million.
“The increase in our estimation for the cost of construction is based on assessment of the scope of work for the build alternative selected in the EA, and the increased costs we are seeing in the construction industry,” Kunishige said.
Constructed in 1932, Waiaka Bridge is a 26-foot wide and 38-foot long concrete bridge with a bolted 3-foot wooden walkway on a sharp corner at the bottom of a hill.
The National Bridge Inventory Standards, which inspects and rates bridges on a scale of 100 to a low score of 0, gave Waiaka Bridge a sufficiency rating of 26 and identified the bridge as “functionally obsolete.” Bridges deemed “functionally obsolete” typically do not have adequate lane widths, shoulder widths or vertical clearances to serve traffic demand.
As planned, the existing Waiaka Bridge will be replaced with a 53-foot wide by up to 80-foot long bridge with the capability to accommodate two lanes of vehicle travel, a shoulder/bike lane and a raised sidewalk. In addition, the roadway approaches would be realigned to improve line-of-sight for motorists and create a smooth transition to the bridge. A roundabout would replace the current T-intersection of Kohala Mountain and Kawaihae roads.
The new, larger bridge will also improve hydraulic conditions for Keanuiomano Stream, which has been known to over-top the bridge during large storm events and flood neighboring properties.
During construction, which is expected to take over a year to complete, a temporary bypass road and bridge will be constructed to reduce traffic impacts.
The recently released environmental document comes over a decade after the state first released a draft EA in July 2011 to replace the aging bridge. The document was pulled in 2016 as a result of “new circumstances and information that might require additional studies.”
In July 2019, the state said it was in the final stages of contracting a consultant to conduct the new environmental assessment released this month for the project. At that time, officials hoped the environmental studies and design work would have been completed by the end of 2021.
“Large preservation projects such as bridge replacement or rehabilitation require planning and environmental documentation in accordance with federal and state law. In the case of our Kawaihae Road, Replacement of Waiaka Bridge and Realignment of Approaches, HDOT withdrew the initial State Environmental Assessment (EA) to meet changed parameters. We restarted the EA process in 2020 to ensure compliance with environmental regulations and to analyze additional alternatives to minimized impacts to neighboring parcels,” Kunishige said of the process.
The 464-page final EA can be viewed at https://bit.ly/3aCFvaS.