Rail. Lava. GMOs.

On the horizon for Hawaii this year are tough issues that will likely define the future and dominate the headlines.

Although it’s not a big election year, politicians nonethe­less will likely remain in the spotlight as a new governor steers at the helm, legislators wade into controversial issues from medical marijuana to funding for the University of Hawaii, and constituents call on county officials to tackle everything from potholes to homelessness.

Among the many issues ahead in 2015, however, three stand out: Oahu’s rail project, the Hawaii island lava flow and GMO regulations.

Crossroads for rail

Oahu’s elevated rail transit system is taking shape in dramatic fashion. Columns and track now line stretches of the south shore. Drivers in central Oahu sometimes find themselves snarled in traffic as the construction heats up.

But even as rail work speeds ahead, several worrisome questions have arisen.

Some of the answers should arrive in 2015. Or, at the very least, the answers will come into better focus for what’s now an estimated $6 billion project.

Here’s what was still hazy as of Dec. 31, 2014 — and what rail officials need to address this year:

» How much will rail ultimately cost to build? Officials last month signaled that the project could run anywhere between $500 million to $750 million over budget, but that estimate comes before any bids have been submitted on key remaining construction contracts.

» What will the second half of the rail line heading into town look like? Those design-and-build contracts haven’t gone out to bid yet.

» How will the transit system’s annual operations costs be covered? Those costs would be at least $110 million starting in 2019, based on estimates given about four years ago.

» Will state lawmakers be convinced to lift the sunset on the general excise tax surcharge, and will all the GET revenues that have been counted on to fund most of the project come through? Despite lengthy consultations from state tax department workers, they still don’t understand why the project isn’t receiving more of those GET dollars.

In March, rail officials expect to open the first bids on their latest requests for proposals to build stations in West Oahu. Those bids will help indicate whether efforts at reining in costs in a hot construction market are working.

Requests for bids to start building what’s left of the guideway heading into town, as well as the accompanying stations there, won’t go out until February or early March, rail officials say. They should start awarding contracts for that work in the fall or winter of 2016.

Aside from all the financial questions, this year island drivers will continue to contend with lane closures and traffic delays as rail construction progresses.

The most intense area for lane closures is expected to be at the H-1/H-2 merge, as crews will spend nearly the full year extending rail’s concrete elevated guideway over the H-1 freeway. Crews will continue to work on the rail route along Kamehameha Highway, doing utility relocation and work to lay the columns there. They’ll also continue to erect rail columns making their way east through roughly Waipahu, rail officials say. — Marcel Honoré

Unpredictable Pele

Today, lava scientists and county officials have much more sophisticated tools at their disposal to better track and map the flow of lava emanating from Kilauea Volcano. But even in 2015, it will be impossible to know for certain exactly what Madame Pele will do next — and when.

Since it crossed into Pahoa in October and set its first buildings ablaze, a river of fire streaming out of Earth’s crust has continued to torment and tease Hawaii island officials and residents about what it will do next — and when.

Unlike the two hurricanes that threatened Hawaii island in 2014, the lava flow from Kilauea has generated months of anxiety and concern.

Homes, businesses and schools have been evacuated — often amid tearful, emotional farewells. Roads threatened by 2,100 degrees of lava have been closed and new ones created to serve as emergency routes into and out of the Lower Puna District.

At one point, the lava appeared destined to overrun Pahoa Village Road, Pahoa’s main street, then inexplicably stalled just 480 feet away.

Now a new breakout of lava from the flow continues to threaten the main shopping area, Pahoa Marketplace.

The eruption from Kilauea Volcano’s middle East Rift Zone has been going on since Jan. 3, 1983. But the flow that’s made a circuitous, 13.5-mile path into Pahoa broke out from a new vent on June 27 and has had residents of Hawaii island’s Puna District on edge since August, when it first took a bead on rural Kaohe Homestead farms and buildings before suddenly changing direction.

"The June 27th lava flow surprised everyone by entering a deep ground crack, emerging some distance downslope, and eventually extending about (13.5 miles) from the vent — the farthest distance a lava flow has reached during the current eruption," Jim Kauahikaua, scientist-in-charge of the U.S. Geological Survey’s Hawaiian Volcano Observatory, said in an email.

The stop-and-start behavior is similar to what happened when lava wiped out homes in nearby Kalapana in 1990.

"The Kalapana flows were interrupted a few times by fluctuations in lava supply, and when the lava supply resumed, the flows responded with breakouts — something that we’re seeing today," Kauahikaua wrote. — Dan Nakaso

GMO revolution

Following a tumultuous year that saw uprisings in three different counties, look for more unrest in Hawaii over the planting of genetically engineered crops in 2015.

But will the revolution finally come to Oahu?

Most definitely, says Ashley Lukens, program director for the Hawaii Center for Food Safety, which helped community groups in their campaign to establish a moratorium in Maui County on genetically modified organisms, or GMOs.

"After the Maui election, I must have gotten 30 phone calls from some well-respected people who said, ‘We want to be next.’ They said we want to make sure our residents are protected against the expansion of the agrochemical companies on Oahu," she said.

Lukens predicted the next high-profile battleground in Hawaii will be at the state Legislature, which meets the third week in January.

"People are really frustrated," she said. "This is not an issue anyone can ignore anymore."

On Maui, the initiative that voters passed in the Nov. 4 election was put on hold until March 31 following a court appeal by Monsanto and others who are expected to take a financial hit by the new law.

County ordinances calling for GMO and pesticide regulation on Kauai and Hawaii island were also struck down by the same judge who ruled those measures are pre-empted by state law.

But don’t expect the 9th Circuit Court to make a ruling until after 2015, said Paul Achitoff, attorney with Earthjustice in Honolulu. Opening briefs aren’t due until Friday.

On Kauai, meanwhile, the state and county are planning to examine possible health and environmental impacts associated with the use of pesticides applied to GMO crops. A fact-finding panel won’t produce original research but will collect, summarize and discuss existing evidence. — Timothy Hurley