Two Denver firms have been chosen to design the estimated $20 million maintenance and office facility for the planned streetcar line expected to begin construction this summer in downtown Kansas City.

RNL Design will be the lead architect for the two-story building and Maintenance Design Group will serve as lead consultant on the project, Richard Shiffer, a senior principal at RNL, said Thursday.

Shiffer said RNL Design and Maintenance Design Group have had extensive experience designing transit facilities for buses and rail throughout the United States.

Both Colorado companies have been hired as subcontractors by HDR Engineering of Kansas City. The Kansas City Council awarded HDR a $700,000 design contract for the streetcar project in January. Luke Olson, central region streetcar director for HDR, said the exact location of the maintenance facility has not been determined.

The three potential sites being considered are roughly along Holmes Street between Second and Third streets in Columbus Park, the neighborhood just east of the River Market across Missouri 9, according to the city streetcar website.

One location is undeveloped, the second has a structure on it and the third is occupied by light industrial use, according to the city.

One of the locations along Third Street could be incorporated into a mixed use or commercial development at street level in support of a current redevelopment plan for Columbus Park, the city study noted.

Olson said the dimensions of the maintenance facility have not been determined, but it will have to be large enough to accommodate the four streetcars that would be acquired for the initial line.

The building also will be designed to the LEED Gold environmental standard established by the U.S. Green Building Council.

The city’s schedule calls for construction to begin this June on the two-mile streetcar line that will connect Crown Center with the River Market. The route of the $102 million project will follow Main Street and the streetcar is expected to begin rolling by mid 2015.