In its last weeks in power, the Obama administration is helping speed up environmental review of California’s plan to build twin tunnels through the Delta in an effort to overhaul the state’s water delivery system. U.S. Interior Secretary Sally Jewell on Wednesday issued an executive order directing federal wildlife regulators to issue an initial opinion by Jan. 17 on whether the $15.7 billion tunnels would harm endangered fish species — a key ruling in the future of the project.