Warning Warning focuses on San Francisco Bay ecological conditions in 1970 and threats to the Bay caused by the dumping of municipal, farming and industrial wastes into its tributary rivers and into the bay itself. The film was made in support of the Save the Bay movement that succeeded in stopping further land fill operations. In the 1960's, the Army Corps of Engineers projected that San Francisco Bay would be completely filled down to narrow shipping channels, and that the earth from the San Bruno Mountain south of San Francisco would be used to fill it. Bay area conservations launched a movement to Save the Bay. This organization led efforts that resulted in the creation of the San Francisco Bay Conservation and Development Commission and state legislation to stop the destruction of the bay. The Commission was used as a model for the creation of the California Coastal Commission and the conservation and preservation legislation that now has put a stop the the wholesale destruction of the environment of the coast and the bay. Harvey Richards made Warning! Warning! to help build public support for the Save the Bay movement.