While all Americans have been advised by healthcare professionals to practice "social distancing" or to work from home if possible in order to "flatten the curve" of active coronavirus cases, the question looms as to when and where more-stringent pandemic containment measures may be enacted.

The problem? Many utility workers could be hard-pressed to perform their critical roles if they become subject to a shelter-in-place order.

"Those who have the ability to work from home are trying to set this up, but there are obviously a lot of our members who aren't able to do this," said Utility Workers Union of America President Jim Slevin in an emailed statement. According to the union, essential power plant, utility or grid operator employees currently are not legally required to continue working during an emergency.

Perhaps because of that lack of a requirement, U.S. electric utilities as a whole do not have one across-the-board policy guiding their staffing decisions during the COVID-19 pandemic, and their individual responses to S&P Global Market Intelligence inquiries regarding any plans they may have to sequester essential workers varied.

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Some utilities prepare to shelter in place

In Minnesota, the state's second-largest electric power supplier has made preparations to sequester key employees on-site should the need arise.

Following the guidelines in a pandemic plan prepared after the H1N1 flu outbreak in 2009, Great River Energy has cots, sleeping bags and food in place for its power plant and control room operators. The wholesale electric power cooperative also is making sure employees have access to showers if they are called upon to stay on-site for one or two week shifts, said Mike McFarland, director of enterprise risk management for Great River Energy.

"The biggest thing would be making sure that staff that are sequestered at work are comfortable and able to continue for a length of time," McFarland said.

Making the sequestration call likely would depend on the number of infections experienced by the most critical staff. Great River already has told employees who can work from home to do so and taken other social distancing measures, such as holding meetings via teleconference whenever possible.

"The extent to which people are taking care of themselves and their families [via social distancing] is the extent to which we won't have to go into sequestration," the director said.

Employees at CenterPoint Energy Inc. "who work in control rooms and similar environments with critical or limited personnel are working in isolation to avoid potential exposure to the virus," according to the Houston-based multiutility. Arrangements typically used during hurricanes or other severe storms already are in place to house and feed CenterPoint Energy employees for several days.

At NorthWestern Corp., which provides electricity and natural gas services to roughly 734,800 customers in Montana, South Dakota and Nebraska, no employees have been sequestered on-site, but the utility says it has the resources to do so if need be.

"Plans are in place so that in the event one of our workgroups does shelter in place, that group has access to kitchen, shower and other facilities necessary, along with supplies," NorthWestern spokeswoman Jo Dee Black said. In the meantime, she added, many employees are working from home, and those who cannot are doing their jobs in separate rooms on-site with minimal interaction.

A representative for Boise-based Idaho Power Co. said the utility already has implemented its pandemic response plan, "which does provide for the possibility that essential employees would need to be sequestered," but declined to provide any specifics as to what aspects of that plan have been activated. On the East Coast, ENMAX Corp. utility Emera Maine is separating its employees from their larger workgroups into "small pods," among other "levels of isolation." The utility acknowledged that it has the ability to keep control center employees "fully self-contained" on their property.

American Electric Power Co. Inc. spokeswoman Melissa McHenry said that utility has "not yet" asked employees to shelter in place at work but currently is procuring provisions to allow for sequestration at certain facilities.

"No plans to sequester at this time"

Not all utilities said they are making preparations to house essential employees on-site.

While Consolidated Edison Co. of New York Inc. is considering all kinds of scenarios, the company that delivers electricity, natural gas and steam to 3.5 million customers in New York City and Westchester County, N.Y., has no plans to keep employees on-site at the moment, spokesman Philip O'Brien said.

"The virus itself, of course, does not have an effect on the utility's operations. It has an effect on people," the spokesman said. "So far, we are more than capable of managing this."

The company's administrative employees are working from home, O'Brien said, and many of those reporting to work are field crews, control room operators and system managers for each commodity.

But to ensure the health and safety of customers and employees, Con Edison has suspended all home visits that are not in response to an emergency or a service connection request. The company also has taken other safety precautions, such as assembling field crews in open spaces big enough for employees to maintain a safe distance from one another while getting assignments.

Duke Energy Corp. in a statement said it does not have any plan to sequester employees but has "instituted additional worker screening measures (like temperature checks) at generating and other critical facilities ... [and] initiated split operations for critical operator functions between primary and alternate locations, as possible, to limit potential exposure and maintain operations."

And in New Hampshire, Unitil Corp. said that it has "no plans to sequester at this time" but is "prepared to escalate should local conditions warrant doing so."