Maine transportation authorities are frustrated by an eight-month delay in the Sarah Mildred Long bridge replacement in Kittery and believe it can be opened to traffic earlier than mid-May, the date estimated by the project’s contractor, Cianbro, the Pittsfield-based construction giant.

The delay is not warranted by “routine” work that needs to be completed on the bridge, Maine Department of Transportation spokesman Ted Talbot said in response to a series of emailed questions. The department said it is weighing all options to speed up the bridge’s opening.

“We believe that almost all the work … that requires bridge closure can be accomplished safely after the bridge has been opened to traffic with either a temporary lane closure or a short duration off-peak full closure,” Talbot said. Given the monthslong delay so far, he added, “we believe our contractor should share the same sense of urgency that the department and the public share to open the bridge.”

This week, Cianbro presented an updated work schedule that pushed the bridge opening to May 10, more than eight months after the September 2017 deadline.

Cianbro has been paid almost $160 million to date for the project, according to the department. Because of the delays, however, it could face a penalty of $1,000 per day after the bridge was supposed to be open to traffic, according to its contract. It is not currently accumulating those fines, according to Talbot.

“The department will take a fair look at all issues related to the delay once the bridge is open and evaluate how to proceed via the contract,” Talbot said.

Cianbro was on track to open the bridge in October – slightly late – until last July, when it pushed the schedule back to April, according to the Maine DOT. The delay was blamed on Cianbro’s concern about late-season paving and striping on the bridge, which remained a stumbling block to opening it into November.

According to Talbot, the Maine DOT committed to provide its own workers and equipment to complete the paving and striping, but since finishing the work, it received updates projecting the bridge would be open by the end of January.

“Now, to the department’s surprise, Cianbro’s latest schedule has projected the bridge to be opened in May 2018,” Talbot said.

“The department’s frustration comes from the later schedule updates, which continue to push out the opening dates for new reasons and work items that the department believes should have been accomplished earlier, or, in some cases, are better suited to be done after the bridge is open with appropriate traffic controls in place.”

In a phone interview Friday, Cianbro spokesman Alan Grover said the company would not comment on the bridge project.

“Really, the entirety of Cianbro’s point of view right now is that out of respect for the DOT, we suggest you refer all your questions to Maine DOT spokesman Ted Talbot,” Grover said.

Cianbro has been paid about $159.8 million to date, the bulk of its $163.7 million contract, according to the Maine DOT. The total cost of the bridge is $164.8 million, including costs for real estate leases, fees, environmental impacts and acoustic monitoring, making it one of the most expensive bridge projects in Maine’s history.

The bridge is one of three that connect Kittery and Portsmouth, New Hampshire, over the Piscataqua River.

The lift span was officially commissioned in late January, after it was successfully lifted and tested under different scenarios, Talbot said. Maine and New Hampshire, which jointly own the bridge, have trained crews who are waiting to take over operational duties, the Maine DOT said.

Most of the remaining work is routine and either “aesthetic or weather-dependent” like weather-proofing, paint touch-ups and concrete patching, according to the department.

“Determining when the bridge is ready to open is the contractor’s responsibility,” Talbot said. “The department does have some options available under the contract to expedite the opening and are carefully evaluating those options, as some would have an effect on contract time and compensation.”

Work started in 2015 to replace the original Sarah Mildred Long bridge, opened in 1940, in the same area. A malfunction on that bridge in 2016 left the lift stuck in the up position, and it was demolished that year.

Before it was demolished, approximately 15,000 vehicles used the original Sarah Mildred Long Bridge every day. Those vehicles have been diverted to Interstate 95 for the last year and a half.