Well, I consider that to be mostly nonsense.  The Nunes position paper is nothing but a polemic.

"Environmental water use falls into four categories: water in rivers protected as "wild and scenic” under federal and state laws, water required for maintaining habitat within streams, water that supports wetlands within wildlife preserves, and water needed to maintain water quality for agricultural and urban use. More than half of California’s environmental water use occurs in rivers along the state’s north coast. These waters are largely isolated from major agricultural and urban areas and their wild and scenic status protects them from significant future development. In dry years, the share of water that goes to the environment decreases dramatically as flows diminish in rivers and streams. During this latest drought, the state also reduced water for the environment to reserve some supplies for farms and cities. "

http://www.ppic.org/main/publication_show.asp?i=1108