By: HISTORY.com Editors

1977

Over 2,000 protesters occupy the Seabrook Nuclear Power Plant construction site

Published: January 26, 2023

Last Updated: May 28, 2025

On April 30, 1977, more than 2,000 protesters occupy the Seabrook Nuclear Power Plant construction site in New Hampshire; 1,414 of these activists are arrested in what becomes one of the largest mass arrests in American history.

Anti-nuclear demonstrators set up tents and toted signs reading “Split Wood, Not Atoms” and “Go Fishing, Not Fission” as they occupied the property for nearly a day. State police were deployed to dissolve the occupation, and the advocates were charged with trespassing on the site of a proposed nuclear energy plant and detained in National Guard armories for up to two weeks.

The demonstrators, known as the Clamshell Alliance, opposed the construction of the $2 billion Seabrook Nuclear Power Plant. Work on the plant had already been halted by the Nuclear Regulatory Commission following the Federal Environmental Protection Agency’s concerns that the plant’s cooling system could endanger marine life.

The demonstration gained notoriety for the mass arrests and helped foment widespread opposition to the plant, which did not go online until 1990, following years of legal suits and other delays.

Through the 1950s and 1960s, nuclear energy was seen as a modern and sustainable means of generating massive amounts of electricity—and a way of out of the energy crises emerging from international oil embargoes. In 1973, the Nixon Administration launched the “Project Independence” initiative to build 1,000 domestic nuclear power plants by the year 2000. However, the number of reactors peaked in the 1990s at 112, and that number continues to dwindle.

Disasters like Three Mile Island in 1979 and Chernobyl in 1986 generated backlash to nuclear power, and economic pressures continue to have a major impact on the demand for more plants—they cost billions of dollars to build and millions a year to maintain, while natural gas is cheap and easy to generate through fracking.

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Citation Information

Article title
Over 2,000 protesters occupy the Seabrook Nuclear Power Plant construction site
Website Name
History
Date Accessed
August 01, 2025
Publisher
A&E Television Networks
Last Updated
May 28, 2025
Original Published Date
January 26, 2023

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