It was indeed a “great day for our state,” as Gov. Josh Green said, when a settlement was reached Thursday with youth plaintiffs who had sued over the state government’s failure to do enough to rein in carbon pollution.

The groundbreaking settlement in Navahine F. v. Hawaii Department of Transportation is the first commitment of its kind by a state in this nation. It places Hawaii in a leadership role to model methods of reducing, and ultimately eliminating, fossil fuel emissions from our transportation sector. That’s a commitment that must be fulfilled — justified by the proven and growing threat to human health and Hawaii’s environment posed by climate-warming carbon emissions.

In 2022, the plaintiffs — all minors and many Native Hawaiian — joined nonprofits Our Children’s Trust and Earthjustice in suing Hawaii’s Department of Transportation (HDOT), its 2022 director, Jade Butay, then-Gov. David Ige and the state. They charged that HDOT was violating their constitutional rights to “live healthful lives in Hawaii, now and into the future” — and backed that charge with the dismaying fact that emissions from the transportation sector were actually rising despite state-established goals to reduce carbon pollution.

As far-fetched or novel as the lawsuit might have first seemed, last week’s approved settlement now recognizes a constitutional right to a life-sustaining climate. And as a matter of state policy, it creates and codifies HDOT’s commitment to transform the state’s transportation system so that Hawaii’s overall emissions from the system are “net-negative,” i.e. reduce or sequester carbon emissions to the extent that they fall to less than zero.

It’s not a stretch, theoretically, to make this commitment, in that Hawaii has already set ambitious statewide goals to electrify the economy and reduce emissions. But as the lawsuit reveals, Hawaii’s dependence on fossil fuels to power transportation has so far overwhelmed the state’s goals. In fact, emissions from the state’s transportation sector are rising, and without changes in policy, will make up nearly 60% of Hawaii’s greenhouse gas emissions by 2030.

The settlement also breaks new ground by binding the state to form specific plans for decarbonization, and by committing to work with the youth plaintiffs by forming a volunteer advisory committee, in a negotiation overseen by HDOT Director Ed Sniffen.

“We’re committing to develop and use greenhouse gas emission measurements and reductions in vehicle miles traveled when we develop ground transportation projects,” Sniffen said, “and look for ways to translate that to our Airports and Harbors projects.”

At Thursday’s news conference announcing the pact, plaintiffs and their attorneys exulted in the possibilities unlocked. “Today’s settlement shows that the state and HDOT are truly committed to transformative action,” said Leina‘ala Ley, an attorney with Earthjustice.

“This new partnership puts climate action in the fast lane,” she said — and that’s right where it should be. Benchmarks in the agreement include:

>> Establishing a Greenhouse Gas Reduction Plan within one year, which must create a roadmap to decarbonize Hawaii’s transportation system within the next 20 years.

>> Creating a lead unit and positions within HDOT to coordinate greenhouse-gas reduction policy, oversee climate change mitigation and adaptation for the highways program, and monitor implementation of Complete Streets, the state’s program to build or upgrade public transportation systems to increase access and safety for non-drivers — youth, pedestrians, cyclists and those with mobility impairments.

>> Adapting the state transportation budgeting process to prioritize reduction of greenhouse gasses and vehicles miles traveled, paired with transparent disclosure of climate impacts of HDOT projects.

>> Making immediate investments in clean transportation infrastructure, to include completion of state pedestrian, bicycle and transit networks in five years, and dedication of at least $40 million to expand the public electric vehicle charging network by 2030.

“You have mobilized our people,” Green said, at the gathering. Now, Hawaii must mobilize the money and personnel to carry out these commitments — plus garner public buy-in and behavioral adaptations — in recognition of the state’s vulnerability to climate change. There is community self-interest in charting a more protective course for our shared environment.

Yes, it will be a tough road, and change and improvements will cost money. This is where Hawaii sorely needs that $25 or more “green fee” — an accommodations fee for travelers that will be dedicated to environmental initiatives and remediation. The governor has seen his proposals for such a fee rejected by the Legislature over the past two sessions. But it’s now time for citizens to make their voices heard when the Legislature reconvenes in January — to follow the lead of these young activists and call for bold legislative action to protect our state, now and for generations to come.