New Melones Dam failing — a highly unlikely event — is one of the safety hazards that are outlined in the Manteca general plan designed to guide growth decisions. But should the 625-foot high earth and rock fill dam that has a maximum capacity of 2.4 million acre feet of water fail, it would flood the entire city of Manteca with water reaching points hundreds of yards north of French Camp Road. The general plan being put together by DeNova Group consultants identifies four dams that, should they fail, would pose a flooding risk to Manteca.