The system's reliability is improved due to the return of a nuclear generating unit in New Brunswick that had been offline for several years, the planned addition of a 660-megawatt transmission line between Manhattan and New Jersey, and added transmission lines in New England.

WSJ: NE power supply helped by conservation, efficiency

But then at 4:00 a.m. on Mar. 28, 1979 a cooling valve got stuck at the Three Mile Island Nuclear Generating Station's Unit 2.

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