Maine’s two investor-owned utilities got what they wanted Tuesday, when Gov. Mills vetoed a bill that would have opened the door to their takeover by a consumer-owned power company.

But the way that Central Maine Power and Versant Power won this round should not leave them feeling very secure.

The bill, L.D. 1708, which had been passed by the House and Senate, would have asked Maine voters in a referendum whether they wanted to force CMP  and Versant to sell their assets to a new nonprofit entity and run the electric grid for public benefit.

But the veto may offer only a temporary reprieve, since the bill’s backers are confident that they can get the signatures needed to bring the question to the voters anyway. That does not give the companies much time to prove that they can improve their performance before fed-up Maine consumers go to the polls. Regulators will also have to act quickly if they are going to show that they can protect the public interest before the public weighs in.

A telling part of Mills’ veto message is that her objections to the legislation were more technical than substantive. She criticized the speed of the legislative process but made no attempt to defend the companies’ performance.

Citing poor service, high prices and a failure to adapt to the expansion of solar power, Mills used terms that could be easily put to use in campaign ads in support of a public takeover.

“The performance of our investor-owned utilities in recent years has been abysmal,” she wrote. “We are well beyond the point of debating whether our utilities can do better. They can and they must.”

And what if they don’t do better? The governor addressed that, too.

She noted that Maine law gives the Public Utilities Commission the power to sanction the companies for poor performance. She pointed out that it can even find them “unfit to provide safe, adequate and reliable service at rates that are just and reasonable” and revoke their monopoly franchise.

That this bill reached Mills’ desk should be a wake-up call for the PUC as much as it is for the companies the commission regulates. Many consumers do not believe that their interests are adequately protected by the regulators – that’s why so many of their representatives in the Legislature voted to take a step as consequential as a public takeover of private companies.

CMP is a small piece of a global corporation headquartered in Spain that delivers energy to 100 million people worldwide. Versant is one branch of a large company wholly owned by the city of Calgary, Alberta. The Maine PUC is the only entity that is expected to put the interests of Maine families and businesses first, but the regulators have allowed CMP and Versant to deliver some of the nation’s worst service at some of its highest prices.

Mills’ veto may not be enough to keep the question of who should own the electric grid off the ballot in 2022, but it should put the utilities and the PUC on notice.

If the companies and their regulators can’t demonstrate that they are capable of improving the performance that Mills describes as “abysmal,” this week’s victory will be short lived.