Sun Tran riders can expect new buses on their routes soon, with the City of Tucson purchasing new natural gas-powered buses to replace the fleet’s remaining diesel buses.

It’s part of the federal government’s infrastructure law, this year pumping $1.7 billion into public transit around the country for low- and no-emissions buses. That translates into 1,700 American-made buses, according to the U.S. Department of Transportation.

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Tucson is receiving $21.4 million of those funds, and will put the money toward 39 new compressed natural gas (CNG) buses.

“We now have the funding in place to eliminate all the diesel buses. Now it’s a matter of getting them procured, and delivered to Tucson,” Deputy City Manager of Tucson Tim Thomure told KGUN 9.

And while the 39 new CNG buses will help lower Sun Tran’s overall emission by 2,480 metric tons, according to the city, Thomure says the ultimate goal for Tucson’s public transit is more ambitious.

“The CNG, while it has a lot of benefits to it, electric buses have no emissions out of the tailpipe. They’re very quiet, they’re a very comfortable ride,” says Thomure. “And so long term, eventually, we would like to have predominately electric buses in our fleet.”

Thomure told KGUN 9 they’re replacing old buses with a mix of electric and CNG buses at this time, planning to acquire buses with the latest electric vehicle technology when they eventually go all-electric in future years.

The City of Tucson is building up Sun Tran’s stock of electric buses as well, using funds from last year’s slightly smaller federal low- and no-emissions bus program grant. The city first added electric buses in 2020.

In addition, Thomure says the city is working on a new program which will harvest methane from the Los Reales landfill and convert it into CNG for the fleet.