Andy Katz is an environmental wonk’s wonk. The East Bay MUD board member may know more about climate change regulations, air-pollution standards, and the importance of urban density than any other elected official in Northern California. He’s a clean-air attorney and public-health advocate for Breathe California and is chair of Sierra Club California. And the Berkeley resident is consistently on the right side of important issues and controversies. He was the leading voice on the East Bay MUD board against the ill-advised — and massive — dam proposed for the Mokelumne River in the Sierra Foothills. The project, before it was blocked by the courts, would have ruined a spectacularly beautiful wildlife habitat and a scenic stretch of the river popular for its fishing, kayaking, and swimming. Katz also has been a consistent voice for water conservation and for levying steep penalties for residents who waste copious amounts of water on their swimming pools, sprawling lawns, and vanity vineyards.