PUNA >> Among major byways in Hawaii County, you can’t get much worse than Keaau-Pahoa Road for hazards or congestion.

Keaau-Pahoa, also known as Highway 130, is the main drag in and out of the fastest-growing portion of the Puna district.

And over the last decade, population growth has overwhelmed the two-lane, undivided route, creating gridlock and pushing up accident rates at several intersections.

The highway has some of the most dangerous intersections in the state. Keaau-Pahoa Road is featured prominently on a list of intersections on state-owned thoroughfares with nine or more crashes from 2007 to 2009, the most recent data available.

In fact, Keaau-Pahoa Road has the top five slots on that list, meaning its intersections have the five highest accident rates of any state thoroughfare on Hawaii island.

State figures show there were a staggering 152 major accidents at the five worst intersections on Keaau-Pahoa Road during the three-year period.

THE HIGHWAY has no stoplights and limited merge lanes.

The influx of traffic as people move into the district has also created bumper-to-bumper traffic: Access to Puna’s major subdivisions — including the largest, Hawaiian Paradise Park — is mostly on Keaau-Pahoa Road.

On average, 35,700 cars travel daily on the roadway, according to a 2009 count conducted by the state Department of Transportation, also the most recent data available.

In 1999, the total was 13,000.

Hawaii County Councilman Zendo Kern, who grew up in Puna and whose district includes Puna mauka, Keaau and Glenwood, said the traffic and high rate of accidents on Keaau-Pahoa Road are among the biggest quality-of-life and public-safety issues for Puna residents.

"It is huge," he said. "When everyone is going home in the evening time, traffic backs up. A drive that would take 10 minutes takes 45."

And avoiding the byway is not a choice.

To get to work or school, to go to the store, to go to Hilo or Pahoa or other neighboring towns, requires a trip on Keaau-Pahoa Road.

"That’s our main access road. That’s all we’ve got," said Puna resident Phil Matlage, who lives in the Hawaiian Paradise Park subdivision. "We have one way in and out of Puna. If we have a tidal wave, if we have a volcanic eruption, there’s no way out of here."

While efforts are under way to relieve the situation, a long-term solution will be costly.

The state Department of Transportation wants to eventually convert Keaau-Pahoa Road into a four-lane highway with stoplights at intersections. But adding a lane in each direction along the 20-mile stretch would cost an estimated $130 million, and there are no immediate plans to include that in the department’s capital improvements plan.

DOT spokeswoman Caroline Sluyter said the department has been working on smaller fixes aimed at improving safety on the roadway and increasing its capacity.

Those include converting south- and northbound shoulder lanes into drivable ones, installing a roundabout at the intersection with Old Government Road, which had the highest accident rate, and widening the "buffer zones" between traffic and pedestrian walkways.

ALSO, STARTING IN MAY, the state will reduce the speed limit along a portion of the highway — to 45 mph from 55 mph.

Matlage said Keaau-Pahoa Road is known among residents as the "flower monument highway."

"At every single intersection, there are flower monuments to the dead," he said.

That even Hawaii islanders are wary of Highway 130 is saying something — the county has the deadliest roads in the islands per capita.

And as more people enter the district, the situation on Keaau-Pahoa Road is poised to only worsen. Thousands more residents are forecast to move into Puna over the next two decades.

That’s worrisome to residents, who say they already leave very early to try to beat the traffic.

Some drivers also get off the thoroughfare and drive on substandard parallel roads through private subdivisions, creating backups in those communities.

Hawaiian Paradise Park resident Frank Soares, 39, a truck driver, said leaving the house after 7 a.m. pretty much guarantees hitting gridlock.

"They’ve got to do something about it," he said.