Davey Medeiros, of Warren, a worker for The Lightship Group, in North Kingstown, carries a power cable past a portable generator into Harrington Hall at the Pastore Complex, in Cranston, yesterday to restore power to the building.

The Providence Journal / Bill Murphy Bill Murphy

CRANSTON — For the second time in a week, a host of state buildings at the Pastore Complex temporarily lost power Wednesday night, when an electrical surge caused underground power lines to fail.

Twenty-three buildings occupied by the Department of Corrections, the Department of Mental Health, Retardation and Hospitals, and other state agencies were affected by the power failure. Backup generators quickly kicked in at all of the buildings, and many switched over to auxiliary generators brought in from outside after two electrical fires Sunday night.

But late yesterday afternoon, eight buildings were still without air conditioning, because their backup generators couldn’t provide enough power. Some had dimmed their lights to conserve energy while others were without lights altogether. State officials said yesterday that additional generators were being trucked in from Massachusetts under the campus’ emergency-response plan and were expected to arrive last night.

On Sunday night, two fires in separate parts of the Pastore Complex burned through cables before being extinguished by the Cranston Fire Department. It was not an actual fire that caused the outage this time, the officials said yesterday at an afternoon news conference.

At about 6 p.m. Wednesday, one main power line failed during the surge, and it caused two other lines to fail, according to James Jerue, director of utilities at the Pastore Complex. Two of the lines had been repaired earlier this week after the damage caused by Sunday’s fires.

Officials could not explain why the power failures were occurring. They said earlier this week that the electrical failures were unrelated to the high temperatures in recent days. Marco Schiappa, associate director of state facilities at the Department of Administration, said they were endemic to an aging network of underground cables.

“I don’t have much information other than it is an old system,” he said at the news conference. “It’s over 30 years old.”

He added, “This is by far the worst it’s been in 25 years.”

The state is in the process of awarding a bid to a company to design repairs to the system, he said. It could take a year for a plan to be drawn up. Comprehensive repairs would follow.

Among the facilities still suffering problems in this latest incident was the Eleanor Slater Hospital’s Adolf Meyer Building, which houses about 100 adult psychiatric patients. The building was the scene of a fire Tuesday that required all patients and staff to be evacuated. Officials said there was no connection between that fire, which was set by a patient, and the current problems.

Power was disrupted at three wings of the Adult Correctional Institutions, but all had transferred over to backup generators.

“I think whenever we’re talking about prisons, we’re concerned about infrastructure,” said A.T. Wall, director of the Department of Corrections, yesterday. “We’ve held our own this week. There has been no compromise in security and safety.”

The outages also inconvenienced some 200 to 300 people a day who visit the Division of Motor Vehicles Operator Control Center in the Harrington Hall Building to get their licenses reinstated, purchase driving records or take part in a driver-retraining program.

Gina Zanni, spokeswoman for the DMV, asked customers to be patient while the agency tried to get back from 50-percent capacity to full capacity.

“This additional problem they’ve been having has really crippled the operator-control system,” Zanni said. “They’re doing the best they can with the little power they have.”

Because of the outside generators already in place, nearly all the buildings that house patients at Eleanor Slater didn’t see much change. Patients on ventilators were not threatened by the power failure, said Ellen R. Nelson, director of the Department of Mental Health, Retardation and Hospitals.

Several hospital administration buildings, however, were without air conditioning and lights yesterday.

Nelson said that hospital workers stayed late Wednesday to ensure that the disruption didn’t affect patient care.

“All of our patients are safe, hydrated and at reasonable temperatures,” she said. “We have some contingency plans should anything change.”

Kwame Larbi, president of AFSCME Local 1350, which represents workers at the hospital, said yesterday afternoon that air conditioning and lights went off, but generators got things up and running.

“We all worked together to make sure our patients were well taken care off,” Larbi said. “Those who needed [it] were all helped.”

State workers and private contractors were scrambling yesterday to fix the lines damaged Wednesday. One crew late in the morning labored to install a portable generator outside Harrington Hall.

“I was on the road when I got a call at about quarter to eleven,” said Davey Medeiros, who works for The Lightship Group, in North Kingstown, the company that delivered the 180-kilowatt generator.

About 20 percent of the power being supplied to the complex’s 100 buildings is currently coming from diesel generators, Schiappa said. It cost the state up to $50,000 just to bring in the additional eight generators yesterday, he said.

Reconnecting the affected buildings to the complex’s internal electrical system will be a long process.

“At this time, I couldn’t tell you when we’ll be back to normal,” Schiappa said.

With staff reports from Karen Lee Ziner

akuffner@projo.com