Five years ago, the Utah Transit Authority announced plans for a new “state-of-the-art maintenance and fueling facility for its growing fleet of clean air vehicles” that it projected would be completed by 2019 and cost $52.5 million.

Now, partway through the project in downtown Salt Lake City, costs have grown to an estimated $95 million, up 81%.

And completion now is not expected until early 2023.

“Costs were pretty conceptual” when those first estimates were made, UTA spokesman Carl Arky says about the project called the Depot District Clean Fuels Tech Center. It is being built behind the agency’s headquarters at 669 W. 200 South.

Last year — after the agency had learned more about environmental conditions at the site and better defined project needs and eventual size of facilities there — Arky said UTA revised its cost estimates to $77 million.

Now a year later, costs again have risen another $18 million to an estimated $95 million. Arky says that reflects the completed design of a main building, plus design of future phases that is about 30% complete.

The UTA board received a report this week explaining the cost overruns and delays. Board members did not criticize the cost hikes, but they did ask several questions seeking to ensure the current design can handle future needs of the “clean fuel” portion of its bus fleet that operates on electricity or compressed natural gas instead of diesel.

David Osborn, a new UTA project manager, explained numerous reasons for the higher costs and delays, including:

• Higher labor and material costs. UTA says its project has been competing for labor and materials with several huge construction projects around the Wasatch Front including a $4 billion Facebook facility, a new state prison approaching $1 billion, the $4.2 billion new Salt Lake City International Airport and several large highway projects, among others.

“So there’s a lot of competition for skilled labor and materials to get construction work done,” Osborn said. “Inflation is a little bit higher than what we would normally want to see. And so that’s driven some of the cost increases.”

• Bad surprises. UTA once planned to use an old locomotive building on the site as part of the project but found that its condition and renovation costs made that unfeasible — so it had to be demolished. Other planned facilities had to be enlarged to compensate for its loss.

Also, “we’ve come across a lot of things in the ground as we’ve excavated,” Osborn said. “There’s been old foundations and footings that need to be removed. ... There are contaminated soils on-site and those need to be disposed of properly.”

It even found a huge, forgotten propane tank buried where key utilities needed to placed.

• Changing needs. UTA has started adding electric buses to its fleet since the facility was originally proposed, so designs were updated to allow maintaining and charging them — including adding solar panels to help.

Also, transit agencies nationally have started using more double-decker buses. Since the new facility is designed to last at least 40 years, the agency decided to make maintenance bays higher and wider to allow potential use of double-decker buses here.

The facility was initially designed to have a first phase that could handle 150 buses or so, and allow later phases in the future that could handle up to 250.

Projections changed about how quickly the agency may need to handle those extra buses. So officials decided to beef up the initial phase to include all utilities and some other facilities that were originally envisioned for future phases.

“Now, it’s looking like we’ll be expanding and having more buses, potentially up to 200 plus within five to six years of the facility opening,” Osborn said.

“It just felt like based on that, that it made the most sense to construct the building to the size that it needed to be for full future use at this time, rather than doing a project and then three or four years later coming back and doing another project [that] would be very disruptive to operations.”

The redesign and handling the unexpected problems took some time, as did obtaining needed permits. Osborn said completion is now expected in early 2023.