The Loop Trolley remains on target to open this spring, although some details — such as the fare amount — have yet to be pinned down.

Chris Poehler, administrator of the Loop Trolley Transportation Development District, and Les Sterman, president of the Loop Trolley Company, gave an update on the project Thursday at a Citizens for Modern Transit event.

Construction on the 2.2-mile electric trolley line began in earnest in the spring of 2015. In the Loop, the trolley will share Delmar Boulevard with cars, similar to a bus, pulling out of traffic at designated stops.

It will run on a single track in the center median east of the Pageant on Delmar and will head south onto DeBaliviere, continuing on a single track on the east side within a new greenway. It will stop and reverse direction at the Missouri History Museum.

The trolley’s cost originally was estimated to be $43 million, but climbed to $51 million due in part to street paving and landscaping costs.

Supporters say the trolley is spurring development and will be a boon for businesses when it brings in visitors. They also say that even with the additional costs, the trolley is being built for significantly less than streetcar lines in other cities.