This week's decision by California's water resources control board amending the water right licenses of Los Angeles to protect Mono Lake is "a significant step in reforming our water supply projects to ensure environmental sustainability of important natural resources," says UC Davis law professor Harrison C. Dunning. Considered a turning point in nearly a century of controversial water wars in California, the decision prompted the city to declare peace in the historic battle. Dunning says the "public trust" precedent will be particularly attractive for environmentalists because it allows a legal intervention -- and perhaps protection -- well before species are threatened or endangered. A nationally known water rights expert, Dunning was closely associated with developing the legal theory used in the Mono Lake litigation. Papers by Dunning and others involved in a 1980 UC Davis water law conference organized by Dunning helped lay the legal foundation for subsequent court rulings that extended the protection of public trust resources to Mono Lake. Dunning's former students helped represent all three interests in the recent decision -- the environmental challengers, Los Angeles defenders and state water board decision-makers.