The new chapters of the Bay Delta Conservation Plan look at the effects of the project on endangered species like Delta Smelt and Chinook salmon.
Fish and wildlife scientists expect conditions to improve for Delta Smelt in wet years, but remain about the same in dry years. Mark Cowin is with the Department of Water Resources.
"We don't expect to have improvement in every time period, every season, every life history period for each species but we do intend to have a net affect that provides for recovery standard."
They point to ecological benefits that include 100,000 acres of habitat and changes in natural water flow patterns.
Bill Jennings with the California Sportfishing Protection Alliance is highly critical of the project.
"You can't deprive an estuary of half its flow and expect it to survive. And frankly, BDCP is essentially a death sentence for one of the great estuaries in the world."