Officials say it will be nearly a year before the damaged tunnel-boring machine stuck under downtown Seattle can start digging again.

The Washington State Department of Transportation has released a new schedule provided by Seattle Tunnel Partners indicating digging is expected to resume on the SR-99 Seattle tunnel project by the end of March 2015.

The new timeline from STP outlines all the steps they are undertaking to get Bertha back on track, including the excavation to reach the machine and the time they anticipate it will take to complete repairs.

According to the new timeline, they will begin building walls of the underground access pit in late May, followed by excavation of the pit July through September.

The next phase, beginning in October, involves making the actual repairs to the machine. STP plans to remove the cutterhead and replace the main bearing and add a more robust seal system.

Chris Dixon, the project manager for Seattle Tunnel Partners, says the repairs pose a significant engineering challenge and have to be done safely.

By February, they expect to be able to conduct tests on the machine to get her back digging by late March.

Bertha has been stalled since late December. The machine is only one-tenth of the way toward completing the 1.7-mile tunnel. The new timeline delays tunnel boring by up to 16 months, but STP tells WSDOT they hope to recover four months to meet the November 2016 tunnel opening date.

WSDOT says construction on other areas of the project are underway despite the digging delays.

“We’re disappointed by this delay, but believe the schedule is moving in the right direction,” says a release from WSDOT. “We’re also focused on the bigger picture, which includes more than $750 million worth of work at the tunnel portals and elsewhere along the SR 99 corridor. That construction is not affected by the tunneling stoppage and continues full speed ahead.”

Todd Trepaneer, with Washington State Department of Transportation, maintains that this additional delay will not cost the taxpayers any additional money since the contract puts the entire responsibility for delay-related cost overruns on STP.

“Remember this is a fixed-price contract and Seattle Tunnel Partners has the obligation to complete this tunnel and the project for the price that they bid and that is still the plan,” says Trepaneer. “Right now it would be the same cost as the taxpayers were expecting at the beginning of the project.”

The tunnel will eventually carry Highway 99 traffic and allow the removal of the aging Alaskan Way Viaduct along the Seattle waterfront.

The Associated Press contributed to this report.