Carter Wall

Executive Director, Renewable Energy Division, Massachusetts Clean Energy Center

View Carter’s Complete Bio

A few weeks ago, I joined local Lawrence officials and representatives from the renewable energy company Enel North America to celebrate the completion of a revolutionary new crest gate at the Great Stone Dam in Lawrence. This project was the result of a partnership between the Commonwealth and the dam’s owner, Enel Green Power. The new crest gate uses a new inflatable system that improves control of water flow.

Completed in 1848, the Great Stone dam is central to the history of the city of Lawrence. The water behind the dam was diverted into canals that produced water power to power the mills for which Lawrence became known. Hydro electric power was added in 1981 –“long before ‘green’ power became fashionable,” as Toni Volpe from Enel’s Renewable Energies Division said. This recent upgrade ensures that Lawrence will continue to be a major provider of clean energy in the Commonwealth for years to come.

For many years, the crest gate on the Great Stone Dam consisted of a series of wooden flash boards held by large metal pins, and dam workers heroically undertook the arduous (and dangerous) process of rowing a boat across the top of the dam to insert the flash boards. This picture shows the old wooden gates in place. 

MassCEC provided $1.1 million of the $4.2 million total project costs for the installation of the new inflatable crest gate, which eliminates the need for that terrifying trip out onto the top of the dam, gives dam operators better control of river flows, and provides added public benefits — flood control on the Merrimack River, more clean energy production, fish habitat management and improved worker safety.

For more information on the dam and the new crest gate, visit the Lawrence History Center.