The D.C. Streetcar on Benning Road NE, near the final stop by Langston Golf Course and the outskirts of the RFK parking lot. (Katherine Frey/The Washington Post)

The District Department of Transportation is mulling scrapping its fleet of streetcars in favor of a design with more easily replaceable parts and compatibility for possible extensions east and west, according to officials and testimony to be submitted to the D.C. Council on Tuesday.

In an oversight hearing before the Committee on Transportation and Environment, DDOT officials plan to testify about problems acquiring parts for the D.C. Streetcar’s existing fleet of six cars; three cars initially had to be repaired after being left outside for a time following their purchase from the Czech Republic in 2004, and three others were made in Oregon by a supplier that has since shut down.

“Given that there is already a limited capacity to procure needed parts for either vehicle type, due to one vendor being an international vendor and the other being out of business, parts availability will continue to be limited in the future,” says the testimony, which was first reported by WTOP.

Now, officials say they are considering eventually phasing out the original design. In the short-term, according to the prepared testimony, DDOT can address parts shortages by sharing equipment with other transit agencies.

However, long-term “parts availability will likely require reverse engineering parts and creating a new supply chain for those items, which is a costly endeavor,” the testimony says. “For this reason, DDOT will be exploring a vehicle strategy for future vehicle acquisition that also considers the feasibility of disposal of the current fleet.”

The revelation is the latest setback for the streetcar project, which was envisioned as a vast network connecting much of the District, but launched in February 2016 with an initial segment of 2.2-miles linking Union Station to a stretch of H Street Northeast. Proposed extensions stretch to the Benning Road Metro station, a segment expected to open in 2024, and up K Street to Georgetown after that.

In a 2015 accounting of Streetcar expenses, DDOT estimated the cost of the vehicles and other capital equipment at $21 million. Despite the testimony, DDOT spokesman Terry Owens said the agency has no plans to get rid of the existing cars. The process of acquiring new cars can take five years, he said, so the agency is starting now.

“DDOT currently has no plans to discontinue use of the current D.C. Streetcar fleet,” Owens said. “As we make plans to purchase additional vehicles for extensions to Benning Road and Georgetown, we are evaluating the capabilities and cost effectiveness of new vehicle types as well as their compatibility with the current fleet.”

Owens characterized the fleet evaluation as a “planning effort.”

He said it includes “evaluating the vehicles currently in service to determine the best fleet management approach to achieve the system’s performance goals.” The streetcars were built to last for decades.

The streetcar served close to 90,000 passengers last month, with an average weekday ridership of about 3,000 trips, the agency said. DDOT initially had planned to charge a fare for streetcar trips, but officials were unable to install a fare collection system in time for the launch. Plus, they said, they wanted to boost initial ridership by making rides free.

In testimony prepared for the council hearing, DDOT said it has no timeline, or plans, to begin charging fares.

“Details of any payment policy will be announced if DDOT makes a change in fare policy,” it says.

Michael Laris contributed to this report.