The Maine Public Utilities Commission voted Tuesday to open an inquiry into responses by the state’s electric companies in restoring power after last October’s destructive storm.

It asked Central Maine Power and Emera Maine to file a report detailing their responses and lessons learned in 30 days. It also said it wanted to know how electric utilities and regulated phone companies worked together and whether changes needed to be made.

The potent pre-Halloween wind and rain storm cut service to more than 400,000 CMP customers and left some in the dark for up to 10 days. In eastern and northern Maine, roughly 90,000 customers served by Emera Maine also lost power. It took eight days to get everyone back on line.

Taken together, it was the largest power outage in state history.

The PUC’s inquiry will operate in parallel with reviews set to be undertaken by the Office of Public Advocate and the Maine Legislature.

In the storm’s wake, frustrated residents and critical politicians are calling for someone to be held accountable for what they see as utility failings in quickly restoring power and keeping customers informed about restoration status. CMP recently revealed that the storm took down its smart-meter network for a time, degrading its ability to recognize what was happening on the system.

There also are calls — in the most forested state in the nation, where tree branches falling on local electric lines are the leading cause of power outages — for more action to prevent future outages.

For their parts, the power companies have said there are lessons to be learned, but that they restored power as soon as they could safely do it. They have said that, with thousands of trees down and hundreds of snapped utility poles, the intensity of the storm defied predictions.

Also pending at the PUC is an estimate of what CMP spent on restoration.

The PUC will scrutinize the request, and could dispute some costs. But by law, customers will pick up most of the tab, which is expected to run into the tens of millions of dollars.

This story will be updated.

Traffic backs up in all directions as a utility worker works on restoring power at the corner of East Avenue and Lisbon Streets in Lewiston Monday morning after a powerful storm wreaked havoc on the area in October. (Sun Journal file photo)

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