SOUTHERN CALIFORNIA—After watching development swallow up vast swaths of land in the 1960s, and stunned by the 1969 Santa Barbara oil spill, a group of California residents galvanized support to place Proposition 20 on the ballot in 1972. A coalition of more than 700 environmental, civic and labor groups came together to form the Coastal Alliance, which powered a grassroots campaign. Senate President pro-tem Jim Mills led a bicycle tour, pictured here, of the coast from San Francisco to San Diego, stopping for press conferences and public events in coastal communities along the route. California Proposition 20, also identified on the ballot as the Coastal Zone Conservation Act, was on the Nov.7, 1972 ballot as an initiated state statute, where it was approved. Proposition 20 created the California Coastal Commission and six regional commissions. It also authorized the State of California to regulate development within a portion of the coastal zone and to provide for the submission of a California Coastal Zone Conservation Plan to the California State Legislature for its adoption and implementation.