The Honolulu Authority for Rapid Transportation has hired a consultant to study whether public-private partnerships should be used to complete the final stretch of the rail project into urban Honolulu.

HART said it selected Ernst & Young Infrastructure Advisors from among eight proposals. The company, a division of the global EY firm, will be conducting a “market sounding/feasibility study,” according to a news release. It will be paid $325,000 for its services, a HART spokesman said.

The public-private partnership approach, often referred to as “P3,” is generally seen as a way to improve the quality and delivery of public-works projects by leveraging private-sector skills and resources.

Ernst & Young will be evaluating the work to build the final 4.3 miles of guideway and stations from Middle Street to Ala Moana Center. HART in August canceled procurement for the construction of that stretch, dubbed the “City Center” section, after the solicitation sat idle for nearly two years.

The consultant is expected to recommend what type of public-private partnership delivery model, if any, would work best for the remaining design and construction of the project, for implementing transit-oriented development and for operations and maintenance.

HART spokesman Bill Brennan said hiring a P3 consultant was self-initiated, but acknowledged the City Council has urged the project to consider public- private partnerships.

He added that Andrew Robbins, who started as HART’s executive director and CEO in September and has previous experience with public-private partnerships for transit projects, viewed the cancellation of the City Center solicitation as an opportunity to consider alternatives to the design-build contracts HART has issued for the work done so far.

The partially built rail line is the state’s largest public-works project. Under the latest estimates, the project will cost $8.2 billion to complete and begin service in December 2025.