In the face of mounting frustration among state legislators over unexpected price increases for the planned New Haven Rail Maintenance Facility, Gov. M. Jodi Rell sent a formal apology to members of the General Assembly on Friday, saying she was unaware the project would cost more money than originally expected.

The letter, which affirms “real” miscommunication on the part of her staff, came just a day after State Senate Democrats uncovered video evidence indicating the governor may have known about the extra costs since 2006. But Rell has maintained that she was unaware of the urgency of the need to find new money until a March meeting with outgoing Department of Transportation Acting Commissioner Emil H. Frankel.

When the rail-maintenance facility was first proposed by Rell in 2005, the state legislature formally allotted it $300 million in bonding. By January of this year, Frankel announced that the $300-million had been allocated as part of an estimate that was “very preliminary” and that the project would ultimately need around $732 million in total.

H. James Boice, who has since taken over for Frankel as acting commissioner, announced last week that the project will need an immediate infusion of $252 million to remain alive.

In the letter she sent Friday, Rell said she was under the impression that the Office of Policy and Management was working to minimize any escalation in budget that was not accounted for in the 2005 assessment with which lawmakers were working.

“I must reiterate that at no time did anyone apprise me of the immediate need for $252 million in bond funds to continue the project,” she wrote in the letter. “This includes several meetings held with OPM officials to prepare the budget and bonding adjustments I presented to the Legislature in February.”

In response to a video Senate Democrats found Thursday that showed her talking in December with then-Deputy Commissioner Boice about a potential price increase, Rell said she thought Boice was referring to general changes in the New Haven rail yard, not just this particular maintenance facility.

Democrats, however, expressed disappointment with Rell and the OPM. State Sen. Bob Duff, vice chair of the Transportation Committee, noted in a Democrat podcast when the news of the price increase was released, “We weren’t sure whether to laugh or to cry.”

In the same podcast, Sen. Donald DeFronzo, co-chair of the committee, implicated Rell, the DOT and the OPM directly, saying there is evidence that the DOT has had information about the cost increase for at least a year.

“You have the Department of Transportation telling us that they need the money, the secretary of OPM saying he’s never heard of this until within the last couple of days and then the governor expressing her outrage about the whole situation and saying she’s going to try to find a way to fix it — but at not additional cost,” DeFronzo said. “Something’s wrong here.”

Still, both Duff and DeFronzo joined Rell in affirming the importance of the project, even if they were unsure how the legislature could work out the details at this point. According to its original blueprints, the facility will include service stations for new rail cars that the state has purchased for New Haven’s Metro-North line.

The upkeep of the new cars will help to boost ridership during a time of increasing energy prices, Rell said. DeFronzo added that the project will also create 200 new jobs in New Haven.

“We’re going to get these new rail cars,” Huff said in the podcast. “We have to have a place to put them. When we ask DOT where they’re going to put them at least in the interim two years, they don’t even know at that point. So, once you start asking questions, there’s even more questions, because they don’t have a lot of answers.”