The state must realign a part of its Saddle Road highway improvement project after the Army acquired 24,000 acres of land near Pohakuloa Training Area that sits on part of the newly aligned highway.

The $220 million Big Island highway improvement project, under way since 2004, is an ambitious effort to straighten, repave and separate military training from motorists.

But with the Army's acquisition from Parker Ranch last year of a section called Ke'amuku, the state Department of Transportation must find a new route for the road that will bypass military operations.

The planned alignment crosses the 24,000 acres, said DOT Highways Deputy Director Brennon Morioka in an Oct. 4 letter. The state wants to minimize contact between military training vehicles and civilian traffic in the Army's Pohakuloa Training Area.

"Consequently, the state DOT will be attempting to establish an alternative alignment which will be infrequently disrupted by military activities and provide an efficient travel route for the general public," Morioka wrote.

Planning studies have been initiated and a supplemental Environmental Impact Statement will be prepared, he said, adding that agency and public informational meetings will be held.

The Ke'amuku land is north of and now a part of the Army's Pohakuloa Training Area that is used by several military branches, said Stefanie Gardin, Army spokeswoman.

"We purchased it as a nonlive-fire maneuver training area," Gardin said.

Built by the Army in 1942, the two-lane Saddle Road extends 48 miles from the rainy Upper Kaumana area east of Hilo to a junction with Mamalahoa Highway six miles south of Waimea.

It connects the Mauna Kea Science Reserve International Astronomical Observatory Complex and the Army's Pohakuloa Training Area to the rest of the island.

Before the beginning of repair work, much of the highway was a patchwork of repaired potholes, winding over and around blind hills and curves as it runs along miles of old lava flows, pasture land and thick rainforest.

Rental car companies had prohibited their customers from driving on the Saddle Road, but local commuters routinely barreled down the center line to avoid the bumps.

The state has completed a section of the road, mileposts 28 to 35, that is now open to the public, said Scott Ishikawa, DOT spokesman.

"There's another section, (mileposts) 19 to 28, that's being worked on," Ishikawa said. "Goodfellow Brothers is looking to complete the work, probably in late summer 2008. There are other phases that they are trying to gradually connect as funding becomes available."

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com.