• Photo gallery: Kapolei Interchange project

Traffic jams can turn a 2-mile drive from Makakilo to the H-1 freeway onramp into a 15-minute ordeal for Shane Ingano, a Makakilo resident who drives to Waianae to visit relatives.

"It’s a killer," he says.

But a new onramp from Makakilo Drive to the H-1’s Waianae-bound lanes will eliminate the circuitous route, pleasing Ingano immensely.

The Department of Transportation is opening the onramp and an offramp to Wet’n’Wild Hawaii on Farrington Highway next Monday.

The ramps are part of the same lane, similar in design to the Lunalilo Street onramp and Vineyard Boulevard offramp near downtown.

Transportation Department spokesman Dan Meisenzahl said the new ramps are part of a four-phase project to improve traffic around the Kapolei Interchange.

The current phase consists of two pairs of onramps and offramps at a cost of $20 million, 94 percent of which comes from federal funds. The next phase, which will begin sometime after 2012, will include a Wakea Street overpass.

Meisenzahl, who gave a tour of the interchange area yesterday, said the newest onramp will allow Makakilo residents to get onto the H-1 freeway, heading toward Waianae, without having to drive through Kapolei.

At the same time as the ramp opening, the state will address a major choke point at the intersection of Kalaeloa Boulevard and Farrington Highway.

To alleviate the bottleneck on Kalaeloa, the department will close the outer lane from the Kalaeloa offramp that heads to Farrington Highway in the Diamond Head direction. Drivers on the Kalaeloa offramp will only be able to go makai on Kalaeloa Boulevard.

At the same time, the state will close the Farrington Highway overpass at Kamokila Boulevard so construction crews can finish the onramps and offramps along the town-bound lanes of H-1.

The state will wrap up phase one by October, when it plans to open the Wakea Street extension on the mauka side of Kamokila. At that time the onramps and offramps along the H-1 town-bound lanes will also open.

The improvements are not universally welcome.

Kris Tyler, owner of Westside Dive & Tackle in Kapolei, said the onramp is needed but questioned the safety of the Makakilo Drive onramp, which is along a downhill stretch of roadway.

"Now people are going to have to stop and make a sharp right turn," he said. "It doesn’t look very safe."

Meisenzahl said engineers tried to address that concern by widening the onramp entrance by 15 feet. He said the department might install deflectors, or plastic poles, to slow traffic in that lane.

Ingano, the driver, who lives in Makakilo and works in Kapolei, supports the changes to what he believes were poorly planned roads around Kapolei. Getting onto the freeway from Kapolei can be frustrating because of the line to turn left turn onto Makakilo Drive, he said.

"With Walmart coming up, that intersection is going to be crazy," he said. "That intersection (at Wakea Street) is going to be necessary. It’s just crazy right now."