Clamshell Alliance campaigns against Seabrook Nuclear Power Plant, New Hampshire, 1976-1989


Delay of construction, dramatization and publication of opposition to atomic power, a shift in energy policy toward clean and sustainable energy, a shift in control of energy production to public.

Ultimately the goal was to prevent the operation of the Seabrook Nuclear Power Plant.

Time period

30 June, 1976 to June, 1989


United States

Location City/State/Province

Seabrook, New Hampshire

Location Description

Seabrook Nuclear Power Plant
Jump to case narrative

Segment Length

2 years, 2 months


Clamshell Alliance


Not known

External allies

Mobilization for Survival

Involvement of social elites

Attorney General Thomas Rath, folksinger Charlie King, Governor Michael Dukakis


Public Service Company of New Hampshire, Governor Meldrim Thomson Jr., Senator Robert Monier, Ron Sher, Captain Sheldon P. Sullivan, Governor Hugh J. Gallen, Governor John H. Sununu, Manchester Union Leader newspaper, William Loeb

Nonviolent responses of opponent

Declarations by organizations and institutions, Newspapers and journals

Campaigner violence

Not known

Repressive Violence

Assault and arrests





Group characterization

Factory Workers
antiwar activists
Native American solidarity activists
Feminists and members of the women’s movement

Groups in 1st Segment

Mobilization for Survival

Groups in 2nd Segment

Attorney General Thomas Rath

Groups in 5th Segment

Massachusetts Governor Michael Dukakis

Segment Length

2 years, 2 months

Success in achieving specific demands/goals

4 out of 6 points


0.5 out of 1 points


3 out of 3 points

Total points

7.5 out of 10 points

Notes on outcomes

Stalled construction for over decade, bankruptcy of major utility shareholder, increased social and financial cost of entering nuclear-energy market

Database Narrative

In July 1976, the Nuclear Regulatory Commission approved the construction permit for the Seabrook Nuclear Power Plant. Leading up to this point, local activists in the small New Hampshire town had attempted to prevent the establishment of a nuclear plant via legal methods such as regulation agencies, the court systems, and a town meeting vote in opposition of the project. Inspired by the success of the nonviolent protests in Whyl, Germany (see “Mass occupation of proposed Wyhl nuclear power plant site in Germany, 1974-1977”), as well as Sam Lovejoy’s victory against a nuclear power plant in Massachusetts (see “Montague, Massachusetts, citizens stop nuclear power plant construction, United States, 1974”), local antinuclear activists met shortly after the announcement of the permit and established the Clamshell Alliance - a coalition of New England antinuclear groups.

The first protest organized by the group was only a few weeks later, on August 1, 1976. This demonstration consisted of between 200 and 600 people (conflicting reports); people attempted to nonviolently obstruct the construction of the plant, and 18 were arrested for criminal trespassing.

Clamshell organized a second protest on August 22 consisting of around 200 people; this group was a splinter group from a larger protest at Hampton Falls Common, about two miles away from the Seabrook plant.  Protesters entered the unfenced construction site and planted small trees and sang songs during the 75-minute occupation. Between 170 and 190 people were arrested – apparently most of those in attendance. Protesters chanted “no nukes,” while being arrested. The coalition continued to mobilize throughout the year, vowing to hold another demonstration the next year designed to halt construction.

The Alliance organized a large demonstration of over 2,000 people less than a year later, on April 30, 1977. This demonstration was one of the major turning points in the Alliance’s history, as well as in the overall struggle against nuclear energy in the U.S. Over 1,400 protesters were arrested for trespassing and incarcerated in the National Guard armories around New Hampshire. Many protesters refused to post bail, and ultimately 550 people were released on their own recognizance (without having to post bail); as a result, the state was responsible for paying the costs of the imprisonment. This, in combination with the huge number of arrests and sympathetic media coverage, was seen as a huge victory for the protesters.

The next large-scale protest took place the next year, from June 23 to June 26. Unlike the other protests, this protest was a “legal protest” – the alliance accepted an agreement from the governor’s office, allowing them space to legally protest at the site for 3 days. Some sources claim this protest was one of the largest on-site protests in the history of the anti-nuclear movement, citing over 20,000 participants and very few arrests.

The meltdown of the Three Mile Island reactor in Harrisburg, Pennsylvania, helped bring safety concerns of the nuclear energy industry to the forefront of national consciousness. This was a turning point in the anti-nuclear movement and helped to swell the numbers involved in protests nationally and catalyzed the increase in the number of anti-nuclear alliances – modeled after Clamshell – nationally. Many of these alliances collaborated to organize a huge anti-nuclear energy rally in Washington, D.C. on May 6, 1979; over 50,000 protesters gathered to promote alternate forms of energy and stress the dangers of nuclear power. Some sources cite as many as 120,000 protesters at the rally.

The anti-nuclear movement had a downtime between 1981-1986 and no large-scale protests were organized during this period. The Seabrook plant finished construction in 1986 and was ready to begin operations in September of that year. Massachusetts Governor Michael Dukakis – citing security and safety concerns, especially with the evacuation procedure – refused to submit the evacuation plan to the Nuclear Regulatory Commission. Protests continued during this year, two noteworthy examples were in May and October, both resulting in dozens of arrests. The completion of plant construction, as well as the nuclear disaster in Chernobyl, Ukraine, both helped revitalize the campaign.

The last large-scale protest took place on June 4-5, 1989, where 687 protesters were arrested for trespassing after climbing a fence at the site using makeshift ladders; two state legislators are recorded as being in attendance for this last protest.

Unit 1 of Seabrook Power Plant went online the next year, in 1990, and Unit 2 was cancelled altogether. The project was completed 14 years after the original proposition, ended up costing almost 7 times the original estimate of almost $1 billion, and ultimately resulted in the bankruptcy of the major utility owner of the project, Public Service Company of New Hampshire. Although the plant ultimately went online, it took over a dozen years more than expected, and its high cost (socially and fiscally) served as a deterrent for companies considering entering the nuclear-energy market; no new nuclear plants were approved for decades after the inception of the no-nuke movement.

Ultimately, the actions of the Clamshell Alliance served as a model for many other anti-nuclear campaigns across the United States and are an extremely significant example of nonviolent protest in the post-Vietnam era.


(1) Ralph Nader, Albert Einstein, labor movement, war resisters, native americans, antiwar movement, disarmament, feminism, antinuclear occupation in Whyl, Sam Lovejoy. (2) Served as the model for the anti-nuke protest wave in the late 70's / early 80's


Clamshell Alliance. About Clamshell. About Clamshell. Clamshell Alliance. Web. Retrieved 26 Sept. 2011. <>.

"Nuclear Power Foes Arrested at Site." Lodi News-Sentinel 23 Aug. 1976. Print.

"The Siege of Seabrook." The New York Times 16 May 1977. Print.

"50 People Conduct Demonstration." Lewiston Evening Journal 2 Aug. 1977.

Useem, Bert, and Mayer N. Zald. "From Pressure Group to Social Movement: Organizational Dilemmas of the Effort to Promote Nuclear Power." Social Problems 30.2 (1982): 144-56.

"Pulling the Nuclear Plug." Time Magazine 123, 13 Feb. 1984. Print

Gold, Allan R. "Hundreds Arrested Over Seabrook Test." The New York Times 05 June 1989. Print.

Gunter, Paul. "Clamshell Alliance: Thirteen Years of Anti-Nuclear Activism at Seabrook." ECOLOGIA NEWSLETTER #3 (1990). Print.

Kenney, Michael. "Tracking the Protest Movements That Had Roots in New England." The Boston Globe, 30 Dec. 2009. Print.

Additional Notes

For more information on the anti-nuclear movement see Bill Moyer. Doing Democracy: The MAP Model for Organizing Social Movements. Gabriola Island, BC: New Society Publishers, 2001.

Name of researcher, and date dd/mm/yyyy

Matt Turner, 26/09/2011