The state’s largest contractor has been selected to build a forensic psychiatric facility in Bangor, which the LePage administration hopes will alleviate overcrowding at Augusta’s troubled Riverview Psychiatric Center.

The state on Tuesday selected Cianbro Corp. of Pittsfield to build a 8,300-square-foot, 21-bed secure forensic “step down” rehabilitation facility on state-owned property on Hogan Road to house patients found not responsible for crimes they have committed or who are unfit for trial. No contracts have been signed.

The new psych center would serve Riverview or Dorothea Dix Psychiatric Center patients who “no longer meet medical necessity for acute psychiatric hospitalization” and who already have permission from the court to leave the facility on occasion, according to the request for proposals for operators that has a Sept. 13 deadline.

The agency that would run the facility has not yet been chosen. The deadline to submit proposals is mid-September.

Under the request for qualifications for the project, the building contractor would purchase 6.28 acres of state-owned property next to the Elizabeth Levinson Center, a 14-bed home for children and young adults who have intellectual and physical disabilities. The land is listed for $495,000. Once the fenced rehabilitation facility is constructed it will be leased to the state for the next 30 years.

“The next steps for this project are for the State of Maine to begin negotiating a lease with Cianbro,” David Heidrich, Jr., Department of Administrative and Financial Services director of communications said. “We will also be working with them to complete the sale of the state-owned land they will be using to construct the secure forensic facility.”

Cianbro competed with Ellis Commercial Development of Hermon and Ouellet Construction of Brunswick, he said. The selection has been finalized, but no contracts have been signed, Alan Grover, spokesman for Cianbro said Thursday. He declined to comment further.

The governor’s office has said the new facility is the state’s best hope for recertification of Riverview, which lost its federal Centers for Medicare and Medicaid Services accreditation in 2013 for overcrowding, inadequate staffing, and for using handcuffs and stun guns to subdue violent patients.

Riverview opened in 2004, replacing the Augusta Mental Health Institute, which began in 1840 as the Maine Insane Hospital. Riverview has dual roles: to treat violent offenders and to assess those charged with crimes to determine whether they understand the charges and are competent to stand trial.

The governor and Riverview officials say the 92-bed facility is filled with patients who no longer need hospital level care, and who take up beds needed for those in crisis.

In June, CMS notified state officials that it is recalling $51 million in payments made to Maine since the decertification. The state is appealing that decision, and will have to repay the money, plus interest, if the appeal fails. The repayment would come from the state’s rainy day fund, according to provisions in the recently passed biennial state budget.