She graduated in 1951 from University of California at Berkeley, according to an obituary article in the Los Angeles Times, and in that same year, she married Jacob Green.

Dorothy Green began her career as a water quality advocate in 1972 when she worked on a campaign to pass Proposition 20, the ballot initiative that established the California Coastal Commission.

In the 1980s, she joined the fight against the peripheral canal, was coordinator of Working Alliance to Equalize Rates, and president of the Los Angeles chapter of the League of Conservation Voters.

[2] Green said the group chose the name because it communicated hope, and her approach of encouraging collaboration among those with contrasting perspectives was the hallmark of her personal style.

I was in a lot of meetings with Dorothy, and it wasn't about stopping things, but always about starting things.”[3] Green headed Heal the Bay for seven years before turning it over to Mark Gold.

She then worked to help establish the Los Angeles and San Gabriel Rivers Watershed Council where she remained its President Emeritus for the rest of her life.

Carolee Krieger, President and executive director of the California Water Impact Network praised Green saying, "She was always willing to tell it like it is.