There's an effort to take the Delta smelt out of the state water-export equation.
California Department of Water Resources officials are saying that there's a population of smelt that has taken refuge far to the north of the pumps outside Tracy. Which means that these fish aren't affected by the pumps. Which means the pumps can be turned back on, since the pumps won't put the smelt in the extinction bin.
Note especially this excerpt from the Sacramento Bee report covering the story:
If (the DWR's effort is) successful, the state would avoid future releases of hundreds of thousands of acre-feet of water for the benefit of the tiny fish – water that could otherwise meet needs of users throughout California.
If it weren't for the Delta smelt, the state's water worries would be over! We could meet the needs of users if it weren't for this insignificant icthyoid!
As noted here, the smelt in this environmental battle is merely a stand-in for the Delta as an ecosystem.
So a new smelt population might not be affected by the pumps. Cool. That doesn't mean increasing the output of pumped water will have no affect on the Delta.
Furthermore, simply getting around the Delta smelt will not solve California's water problems. The state's water issue goes far beyond pumping restrictions, or even a drought. It's rooted in the inescapable fact that, as the system is currently contrived, there isn't enough water to meet the needs of farmers, urban dewllers, and wildlife.
Until that becomes the accepted starting point for discussion, the rest is just window dressing.