While police had yet to identify the woman, relatives said she was Aura "Laura" Garcia, New England Cable News reported.
City police said a bridge worker raising the span for a passing tall vessel didn't see her walking across. Then, when he heard screaming, he lowered the bridge, crushing her.
Family friend David Agosto said Garcia had two children, ages 3 and 15.
"It hurts a lot because she was very close to us and it's not easy you know," Agosto said.
Agosto and other friends and relatives blamed the bridge operator for her death, NECN said.
"It is his responsibility. There should be nobody there on that bridge before he lifted the bridge," Agosto said.