An extra lane is the top choice for reducing congestion in the Waianae-bound lanes of the H-1 freeway near Vineyard Boulevard, the Department of Transportation said.

"It seems like a reasonable idea," said Richard Kawano, a member of the Makiki Neighborhood Board. "It’s not that expensive, and the other options were on the high end—probably more efficient, but way too expensive."

The state says the extra lane would come from re-striping the freeway’s existing three 12-foot wide lanes to create a fourth lane between the Punahou Street on-ramp and the Pali Highway offramp. All four lanes would be 11 feet wide.

Engineers came up with seven options to resolve the bottleneck near the Vineyard offramp. After presenting the options at a public meeting in March, the state collected comments and found the extra lane to be the most popular.

Other possibilities, one of which cost more than $170 million, included left- and right-handed fly-over ramps, a tunnel to Vineyard Boulevard and the continued morning closure of the Lunalilo on-ramp.

Tammy Mori, Department of Transportation spokeswoman, said the department is pursuing the extra lane as the "most favorable option by the community," but is keeping all options on the table.

She said the plan must be approved by the Federal Highway Administration, which could have problems with the narrower lanes and shorter sightlines. The agency will also look at the other options proposed.

Adding the extra lane—and some additional infrastructure—will cost between $5 million and $10 million, Mori said. The federal government could pick up $4.5 million of that cost.

Sen. Carol Fukunaga (D, Makiki-McCully) said she supports whatever solution is safe and helps eliminate the traffic backup.

"The issue of congestion on that ramp has been a big problem for the last 10 to 15 years," she said.

About six years ago, when the state started detouring cars from Lunalilo to the Pali on-ramp during morning rush hour, the problem grew worse, she said.