Caltrans officials told NBC Bay Area Friday that the long delayed Bay Bridge bike path is now slated to be completed by September, some two years behind schedule.

Bay Bridge officials had initially said the path would be completed by fall 2014, then promised it would be done by September 2015. But a string of setbacks pushed completion back.

Caltrans recently overcame the last hurdle to the project — the redesign of the support system for the observation deck near Yerba Buena Island.

On Monday, workers will hoist up three giant beams that will support the path’s observation deck from below. The idea is to test fit them before they will be installed permanently.

Bike advocates can’t wait for the project to be done.

“We have about 4,000 members in the East Bay who ask me all the time 'when are we going to ride to Treasure Island,’" said Renee Rivera, executive director of Bike East Bay. “We’ve had quite a few delays. We’re really hoping it will happen this summer.”

Caltrans has faced a series of setbacks in completing the path. First, the old bridge had to be torn down to allow crews to start construction on the path near Yerba Buena Island. Problems with the safety rail led to $3 million in cost overruns.

More recently, officials said El Nino rain led them to put off the opening date till summer.

In January, questions emerged about the underpinning of the bike path’s observation platform, which will extend some 30 feet out from the edge of the bridge.

The latest design — which relies on three steel beams that cradle the path — was not the first. Two years ago, bridge officials embraced the sleek new design in lieu of an angular bracing system. The redesign was supposed to cost $1.1 million, but is now expected to cost as much as $2.5 million.

Costs escalated after engineers debated how to best attach the giant support beams to the concrete pier at the west end of the bridge.

“That’s been a bit of a challenge,’’ said Steve Whipple, a Caltrans engineer managing the project. He said engineers opted to add dozens of more connecting rods to the design. That meant crews had to find more places in the concrete that would not be damaged by drilling.

“We had to find the right locations where we could drill holes and insert large bolts into it which the cantilever beams will ultimately be connected to.”

On Monday, the giant arms will be moved into position as a trial run to allow for fit up and modifications. Whipple says Caltrans is optimistic that the shored up support system will be finished in time to open in September. “So we’re not expecting obstacles at this point.”

On Thursday of next week, the Toll Bridge Program Oversight Committee charged with monitoring the project will consider some $10 million in contract changes related to both the path and to fight erosion on a nearby hillside known informally as the “Goat Slope.”