Engineer James B. Francis recognized that Lowell needed protection from floods and studied the Merrimack River, understanding the danger created by canals flowing through the city. Although the Guard Locks controlled the normal flow of water into the Pawtucket Canal, he knew the early dam could not contain a Merrimack swollen by melting snow and springtime torrents. In 1850 he built the Great Gate, a remarkable wooden floodgate measuring 25 feet by 27 feet and supported by an iron shackle, but critics mocked it as "Francis’ Folly." At 3:30 A.M. on April 22, 1852, workers used hammer and chisel to drop the gate before the raging river flooded downtown Lowell, thereby saving the city. In 1936, workers dropped the Great Gate for the second time by cutting the iron shackle and sending the 20-ton gate down, and that flood left most of downtown Lowell unscathed. The flood of 1936 also deeply affected young Jack Kerouac, who later invoked it as a symbol of nature’s power in his 1959 novel Dr. Sax.

Photo: Roger W. Sinnott

Photo: Roger W. Sinnott

Lowell, Massachusetts · USA