California is suing the administration of President Donald Trump for what it calls the administration's failure to protect endangered species in the Sacramento and San Joaquin rivers.
California Attorney General Xavier Becerra, the California Natural Resources Agency, and the California Environmental Protection Agency filed the lawsuit on Thursday against the Trump administration in the U.S. District Court for the Northern District of California.
The attorney general said the Trump administration was adopting "scientifically challenged biological opinions that push species to extinction" and harm natural resources and waterways.
The lawsuit stressed the Trump administration's alleged failure to protect endangered fish species from federal water export operations.
In October, the Trump administration announced a plan to divert water to California farmers, fulfilling a campaign promise made by the president.
However, some experts and federal biologists said the diversion would harm fish and drive endangered salmon closer to extinction.
Last August, the administration said it would change the way the Endangered Species Act was applied, making it harder to protect wildlife from multiple threats posed by climate change.
"We are challenging the federal biological opinions, which do not currently govern water project operation in the delta, to protect highly imperiled fish species close to extinction," California Governor Gavin Newsom said.
California has challenged the Trump administration over its environmental policies on dozens of occasions.
Last month, it sued the administration over a plan to open up more than a million acres of public land to oil and gas drilling.
Thursday's lawsuit was filed as a "complaint for declaratory and injunctive relief", the court filing showed.
(Reporting by Kanishka Singh in Bengaluru; Editing by Robert Birsel)