The Butler Transit Authority agreed Tuesday to participate in a joint purchasing program to buy as many as four buses for a possible expansion of the commuter service to Pittsburgh.

Board members unanimously voted to enter the joint purchasing program with several area transit authorities and accept a bid to buy up to four 35-foot compressed natural gas buses costing $744,208 each from Motor Coach Industries, the maker of the authority's existing CNG buses.

The purchases must be made during a five-year period ending in fiscal year 2024-25.

Optional equipment would cost extra, said John Paul, authority executive director.

The authority would pay $744,208 for buses purchased in the first year, but purchases in subsequent years could cost more due to inflation, he said. That potential cost increase was included in the board's motion.

Additional buses could be needed for a future expansion of the commuter service, Paul said. The board will decide if and when to buy any buses, he added.

The authority currently uses four buses for service, which is experiencing a decline in ridership due to the COVID-19 pandemic.

The service is in the last year of a three-year demonstration project funded by state and federal grants. The demonstration project requires the authority to meet ridership levels to keep the service after the end of the three-year period.

In other business, the transit authority board approved a social media policy that includes disciplinary action for employees who speak on behalf of the authority or portray the authority in a negative light in social media postings.