A state proposal to regulate zip line tour companies in Hawaii would cost $400,000 to set up and $350,000 to implement each year, with unclear benefits to making rides safer, Hawaii’s state auditor said Thursday.

State Auditor Marion Higa said in a report submitted to Gov. Neil Abercrombie and the Legislature that there’s not enough evidence to suggest zip lines are seriously dangerous, despite the death of a worker testing a new zip line on Hawaii island last year.

"Generally, we found the aerial adventure course industry, which includes zip lines and canopy tours, has a good safety record, given that certain risks are inherent in such activities," Higa said in the report.

State lawmakers introduced a bill in January to have 22 zip line companies regulated by the Department of Labor and Industrial Relations.

It was referred to the House Finance Committee in March but failed to gain passage before the session ended in May.

Higa said the bill doesn’t provide enough resources to administer the proposed inspections.

The department is already backlogged several years on required inspections of 5,000 elevators, and has failed to inspect amusement attractions already under its jurisdiction, the report said.

"Clearly, the department is not capable of handling its current duties, let alone another inspection program, especially without significant additional resources," Higa said in the report.

The Labor Department said in May that a zip line tower in East Hawaii collapsed last year because of weak soil, sending 36-year-old Ted Callaway of Lahaina plunging to his death. The line was being built along Hono­lii Stream. Another worker was critically injured in the accident.

Higa said it’s not clear regulations would have prevented that accident.