Environmental groups, buoyed by an increase in donations, new pro bono assistance and staff willing to put in long hours amid the Trump administration's rollbacks of environmental regulations, have leveraged those resources to score victories like information requests that contributed to the resignation of the U.S. Environmental Protection Agency administrator and blocking controversial rule delays, according to a recent article by Law360.

One angle of attack has been citizen suits, filed by groups and their members, to enforce environmental laws like the Clean Water Act, according to Wayne Whitlock, a Pillsbury Environmental partner.

"We're seeing it across the board with citizen groups or environmental groups challenging what the federal administration is doing, particularly regarding the Endangered Species Act and the Clean Water Act," he said.

Whitlock told Law360 that he's also noticed an uptick in litigation in one area unrelated to the federal government, because California has a new general industrial stormwater permit, and there are numerous legal challenges relating to its implementation.

"I've seen cases where they're combining citizen complaints under the Clean Water Act and the Endangered Species Act, and that's a very powerful tool environmental groups are using," he said. "Citizen suits are a very complex process and are very expensive to defend. Plaintiffs can shape the way permits and regulations are implemented through them."