San Francisco rightly prides itself on being an environmental leader. Given this deep commitment to protecting the environment, the city’s water agency — the San Francisco Public Utilities Commission — should be a leader in smart, sustainable water policy. Unfortunately, that has not been the case. But Mayor London Breed now has a once-in-a-decade chance to turn the SFPUC in a new direction by appointing a progressive, visionary new general manager who reflects the city’s values.