Five City Council members are pushing for a public hearing on an alternative rail plan given to the city by the Kamehameha Schools.

Under council rules, that's enough support to force the discussion of the plan onto the agenda of a future City Council meeting. The next meeting of the full council is scheduled for Oct. 27.

Hawai'i's largest private landowner commissioned a study that estimated the commuter rail project's price tag could be cut by $1.7 billion by building about half of the planned 20-mile elevated train line at ground level. The city has said a partially at-grade train could save money in the short term but would create safety, traffic and other problems.

The project now is estimated to cost an inflation-adjusted $5.5 billion.

Last month, city Managing Director Kirk Caldwell said a public hearing on the plan would be counterproductive because the city has considered and rejected at-grade alternatives.

Now five council members — Ikaika Anderson, Romy Cachola, Donovan Dela Cruz, Charles Djou and Ann Kobayashi — have written a letter to council Chairman Todd Apo insisting that a public hearing on the plan take place later this month.

Apo yesterday said the council would likely hold a special meeting to discuss the Kamehameha Schools alternative in conjunction with the project's environmental impact statement.

"We will have a public hearing on all that and I foresee doing that sometime in October," Apo said. "That has always been the plan, that when that (final environmental impact statement) came out, which would include the financial plan, we would definitely hold public hearings on them."

The Kamehameha Schools report was conducted by Phil Craig, a New Jersey railway system designer and transportation consultant. His study proposes building the train system at ground level from East Kapolei to Waipahu and from Middle Street to Ala Moana Center. Only the segment from Waipahu to Middle Street, or about 10 out of a total 20 miles, would be built on an elevated guideway.

A reduction in the cost of the rail project could help the city deal with smaller-than-anticipated tax collections needed to pay the city's $4 billion share of the project. However, the city eliminated the ground-level transit option long ago on concerns that it would interfere with road traffic, operate at slower speeds, generate lower ridership and require the acquisition of more right of way.