10.5-mile extension of Daniel K. Inouye Highway shelved in 2018 now back in the works

The extension project that began in 1999 to add 10.5 miles to the well-traveled Daniel K. Inouye Highway on the Big island, but had been shelved twice, now is back on the table, with the state seeking federal funding to pay for it.

Shelly Kunishige, spokesperson for the Hawaiʻi Department of Transportation, said the state is partnering with the U.S. Army to seek defense funding for the extension that would connect the highway, formerly known as Saddle Road, from Māmalahoa Highway (State Route 190) to the Queen Kaʻahumanu Highway (State Route 19).

Hawaiʻi Gov. Josh Green specifically named this project in a letter he sent in November to Secretary of the Army Dan Driscoll proposing $10 billion in federal investments for infrastructure, housing and environmental remediation as part of lease negotiations to allow the U.S. Army to continue using thousands of acres of state land for training and other military uses. The leases includes for use of Pōhakuloa Training Area.

The driving force behind the road extension is better traffic flow, alleviating congestion on Waikōloa and Kawaihae roads caused by military convoys traversing between Pōhakuloa Training Area and Kawaihae Harbor, as well as commercial trucks.

The state Department of Transportation, in conjunction with the Federal Highway Administration, will begin holding public meetings about the extension project, with the first informational open house scheduled for May 20, from 6 to 8 p.m. at Waikōloa Elementary and Middle School, located at 68-1730 Hoʻoko St. in Waikōloa.

The project was first delayed for eight years at the beginning of 2003 while the U.S. Army prepared an Environmental Impact Statement for expanded military training activities at the training area.

The project was shelved again in 2018 due to a lack of funding, according to the Department of Transportation.

That delay came after a draft Environmental Impact Statement was completed in 2017 that detailed three proposed alternative routes. Public hearings and comments were received at that time.

Matt Chalker, a Waikōloa resident, said he would like to see the project completed because military trucks are using Waikōloa Road, the community’s sole route in and out of the community, to get to Daniel K. Inouye Highway when they arrive for training from Kawaihae Harbor.

Military convoys travel Waikōloa Road several times a year, and sometimes several times a month, Chalker said.

The extension would allow these trucks to go straight from Queen Ka‘ahumanu Highway to Daniel K. Inouye highway, with a straight shot to the training area that is along Saddle Road.

The Transportation Department described the proposed project as an “integral element of the road network for cross-island traffic,” connecting transportation users to Ellison Onizuka Kona International Airport and Hilo International Airport, state harbors (Kawaihae and Hilo), beaches and resorts in South Kohala and Kona, and population centers in Hilo, Waimea, Waikōloa Village and Kailua-Kona.

The area that would be developed is currently rolling hills with little to no vegetation. This land is prone to wildfires due to high winds and dry conditions.

The cost of the project has nearly doubled. It has gone from an estimate in 2018 of $80 million to $150 million today, Kunishiga said.

The record of decision for the final Environmental Impact Statement was anticipated to be made in November 2021, Kunishige said. However, because funding sources dried up, Kunishige said the state suspended work on the project because it wouldn’t be able to avoid a re-evaluation of that decision and preparation of a supplemental Environmental Impact Statement when funds did become available.

According to the Draft Environmental Impact Statement in 2017, the highway traffic volume was approximately 3,000 vehicles per day. According to traffic models from the Hawai‘i Department of Transportation for 2024, the daily vehicle number doubled for a portion of the highway from State Route 190 to the Pōhakuloa Training Area, with 6,157 vehicles recorded.

By the year 2035, an estimated 19,400 vehicles per day will utilize the Daniel K. Inouye Highway, the 2017 assessment indicates.

Over the next several months, the Transportation Department will restart the project, including preparing updated Environmental Impact Statements compliant with the National Environmental Policy Act and the Hawaiʻi Environmental Policy Act.

With public meetings beginning again, the draft environmental assessment from 2017 will serve as a starting point for alternative refinements and additional analysis for this project phase.

“No matter what route it takes, it is going to reduce the traffic on Waikōloa Road, which is going to be great,” Chalker said.

As the executive director for Wildfire Safety Advocates, Chalker said he sees the potential for this road to be helpful in fire safety for the community if one of the alternatives presented is chosen, which would add a connecting road from the village to the extended highway.

Construction generally is two to three years after environmental documentation is completed, Kunishige said.

Hawai‘i County Mayor Kimo Alameda is supportive of the extension, saying: “Anytime you can take cars off the road, I think is a win.”