Honolulu Mayor Kirk Caldwell has chosen insurance company executive Colbert Matsumoto to replace Don Horner on the board that oversees the island’s rail transit project, according to a city news release.

Matsumoto, who as Bishop Estate’s court master helped lead the institution out of a tumultuous period in the late 1990s, will attend his first Honolulu Authority for Rapid Transportation board meeting today, the city said. He had also served as chairman of the board of trustees of the Employees’ Retirement System, and currently serves as executive chairman of Island Insurance Co. — one of the top 50 property and casualty insurance companies in the nation, according to the release.

In addition, Matsumoto serves on the board of Oahu Publications Inc., which is the parent company of the Honolulu Star-Advertiser.

Horner, a retired First Hawaiian Bank chairman, resigned his post as chairman of the 10-member volunteer HART board last week. The rail project faces continued cost overruns, schedule delays and uncertainties over whether the city will have enough funds to finish the project. Horner had served as the HART board chairman for about eight months. He was originally appointed in 2011 by former Mayor Peter Carlisle.

“This is a challenging time for HART but I look forward to working with the other directors to restore public confidence in the project,” Matsumoto said in a statement.“HART’s role in shaping Honolulu’s future needs to be responsibly undertaken with transparency and accountability by all involved. I hope to contribute to achieving that outcome.”

Caldwell also announced Wednesday that he’ll reappoint former U.S. Rep. Colleen Hanabusa to the board. Hanabusa had stepped in at Caldwell’s request to fill the remainder of former board member Carrie Okinaga’s term, which expires June 30.

Damien Kim, the vice chairman, will fill in as interim chairman until the board selects a permanent chairman.