The discovery of a 3-inch human bone along the proposed route of Honolulu's elevated rail system is the latest twist that could further delay the controversial $5.3 billion project.

The bone was found Wednesday near the intersection of Halekauwila and Cooke streets in Kakaako by a crew sifting through a trench as part of an archeological inventory survey, or AIS.

Last month, construction of the project was halted after the Hawaii Supreme Court ruled the city must complete the AIS along the entire 20-mile route, rather than dividing the survey into four separate phases.

Once the AIS is finished, the city needs 30 days to prepare a report by the consulting firm Cultural Surveys Hawaii. That report, as well as any burial treatment plans for native Hawaiian burials, is then forwarded to the State Historic Preservation Division for review.

"Once those reports are in, SHPD has 30 to 45 days to review those," said Department of Land and Natural Resources Chairman William Aila, who also serves as a state historic preservation officer.

Dan Grabauskas, executive director of the Honolulu Authority for Rapid Transportation, told his board of directors Thursday he expects construction of the rail line to resume in April or May.

Previously, the city has said it would cost $7-$10 million for every month the rail project is delayed. But, if the delay extends beyond the seven to eight months predicted by Grabauskas, the project's contingency fund could draw down faster than anticipated.

According to the project's July monthly progress report, contingency funds currently total $643.6 million, of which $541.7 million is allocated, and $101.9 million is unallocated.

HART spokesman Scott Ishikawa told KITV4 "allocated" simply means the funds have been dedicated to contracts already issued, not that they will necessarily be spent.

"This does not mean the contingency money can't be tapped for other uses on the project," Ishikawa said in an email.