
Tropical Storm Isaias knocked out electricity to more than 684,000 Connecticut customers Tuesday.
As of 11 p.m. Tuesday, about 568,000 Eversource customers and another 116,000 for United Illuminating were in the dark.
The outage is among the largest in state history and it likely will take days for crews to restore electricity service to hundreds of thousands of customers.
By comparison, the October Nor’easter in 2011 caused more than 955,000 customers to lose power. Tropical Storm Irene that same year knocked out power for more than 600,000 customers. And Super Storm Sandy totaled about 500,000.
Following the 2011 Nor’easter and Super Storm Sandy in 2012, the General Assembly put together a task force to examine the storm response by the utilities. A separate, independent report found that Eversource, which was Connecticut Light & Power at the time, failed to properly prepare for the October snow storm and underestimated the scope of the outage it caused.
Since that time, the company has been allowed rate increases to harden its infrastructure and trim trees. It’s unclear whether that work served to reduce or otherwise limit Tuesday’s outage.

Eversource, which experienced problems with its outage reporting system Tuesday, said it was working as quickly as possible to restore service. Customers without electricity or other service problems are being asked to call 800-286-2000.
The outage comes after a difficult week for Eversource, whose controversial rate increase was suspended by the Public Utility Regulatory Authority.
The rate increase that went into effect on July 1 was pitched as relatively modest, but with more people staying at home because of the COVID-19 pandemic, that rate increase caused sticker shock.
Regulators suspended the increase last week in order to examine its impact.
“The intent of this re-examination is to ensure that Eversource is not over-collecting revenues in the short term at the expense of ratepayers during this period of financial hardship,” PURA officials wrote in a July 31 letter to Eversource.
Eversource officials didn’t argue.
“We will work quickly to enact PURA’s temporary suspension of the rate adjustment and look forward to participating in the process to ensure transparency for customers and policy makers,” Eversource spokesperson Tricia Taskey Modifica said in a statement last week.