The New York ISO will look to falling COVID-19 infection rates and guidance from the state to decide when to begin sending home employees who have been living on-site at two control centers for more than a month.

Although it has no specific date in mind, the NYISO expects to keep the full 37-person team in place until at least May 15. That is the day Gov. Andrew Cuomo has eyed for beginning to reopen, on a regional basis, parts of the state's economy closed by the coronavirus pandemic.

To ensure grid reliability and the health and safety of employees, a volunteer team comprising grid operators, managers, facilities staff and cafe workers on March 23 moved into living quarters set up at two NYISO control center sites near Albany, N.Y. The move came amid the growing coronavirus outbreak in the state.

New York had more than 300,000 confirmed cases of COVID-19, the disease caused by the novel coronavirus, and more than 19,000 related deaths as of May 2, according to the state Department of Health.

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But New York saw declines with respect to total hospitalizations and new cases over the month of April. With signs that the pace of the outbreak is slowing there, the NYISO can start to look for an opportunity to reduce the number of workers in sequestration, NYISO President and CEO Rich Dewey said in an interview. The grid operator is keeping an eye on infection rates in the Albany area, which never climbed to the highs reported in and around New York City and have generally improved in recent weeks.

"I think if we continue to see downward trends in infection rates … we can start to relax a little bit," he said.

Dewey stressed, however, that the NYISO would not end the sequestration until it has a "firm understanding" of what re-establishment of business practices in the state will look like.

The wind-down likely would happen over several weeks and start with employees currently living at one of the two control center sites instead returning to their homes at the end of their shifts, with the reminder to avoid crowds and take other precautions to stay healthy while they are away from the facility. If that phase goes well and infection rates continue to improve, Dewey said, workers living at the second site could follow suit a few weeks later.

Throughout the process, the NYISO would continue to keep one control center for the night shift and the other for the day shift to reduce the risk of cross-contamination.

Once the sequestration ends, the grid operator plans to keep in place infrastructure established to allow employees to live onsite in case the program needs to be brought back to address a subsequent wave of infections.

The NYISO is happy with the decisions it has made throughout the pandemic thus far, according to Dewey. Things have gone reasonably smoothly, and employees are holding up well, he said. A team of medical consultants checks in with the sequestered employees regularly about their physical and mental health.

"They're still very well engaged and everyone is happy and healthy," Dewey said.

He said sequestered workers have found particularly helpful a small team of support staff that was formed to periodically reach out to the employees' families to see how they are doing and whether they have any specific needs.

"They appreciate that," Dewey said. "It's helped operators know their families are OK."

The NYISO has other employees available to step in and take the place of a sequestered worker if needed, according to Dewey. As of now, however, the original team remains in place, although the NYISO has not yet decided whether to swap anyone out if the situation goes on much longer, he added.

The decision to sequester employees is rare among grid operators in the United States. As of April 30, the California ISO, ISO New England, Midcontinent ISO and the Southwest Power Pool had not sequestered staff. The Electric Reliability Council Of Texas Inc. did not have a comment about employee sequestration.

But the NYISO is not alone.

The PJM Interconnection similarly started to sequester a team of control room operators at one its campuses April 11. PJM is not reporting how many employees are involved and has not set a timeline for ending the sequestration, spokesman Jeff Shields said April 30. But the workers are doing well in their new, temporary living arrangements, he said.

Shields said PJM also has retained an epidemiologist to review its pandemic measures, including sequestration and return-to-work plans, facility set up and social distancing policies going forward.

As for the NYISO, Dewey said the sequestration process has shown the dedication of its employees, both those who signed on to live away from their homes and those who did the work that allowed most of the grid operator's other employees to work from home.

"We're lucky to have them," Dewey said.