The U.S. Bureau of Reclamation has cut water releases from 1,100 cubic feet per second down to 500 feet.
"That has exposed some of the fall run salmon nests or 'redds' as they're called, r-e-d-d."
Tom Ghoring is with the Sacramento Water Forum.
On Capital Public Radio's Insight with Beth Ruyak, Ghoring said early surveys show that reductions, prompted by the dry winter, have left 15 percent of salmon nests or "redds" out of water.
"We know that exposing them is harmful to them. An exposed redd doesn't necessarily kill the eggs buried in the redd, but some of the nearby redds that are still underwater may be harmed so much that they could die."
~Tom Ghoring, Sacramento Water Forum
Reclamation officials say reducing water flows into the American River will help conserve the water supply stored behind Folsom Dam.
Insight will have more about how the lack of rain is impacting the region, coming up at 9 a.m.
Record summer heat has increased fire risk in California and the Western U.S. as drought conditions expand.
Statewide water conservation exceeded the mandatory goal in May and Sacramento reduced water use 40 percent.
In the fourth year of drought in California, sales and use of "safe and sane" fireworks are restricted in some areas, allowed in others.
A California Assembly committee will hear a bill Wednesday that would allow water districts to impose taxes on any business, industry or person who wastes water.
The drought can be blamed for a number of problems and the latest is a major decline in the duck population. A new survey shows lack of rain has led to poor habitats.