A revised U.S. Army Corps of Engineers water plan for the Apalachicola-Chattahoochee-Flint River Basin is being challenged by environmental groups that say the Sunshine State is again being cheated out of its fair share of the river system’s flow.Earthjustice on Thursday filed a lawsuit in U.S. District Court for the District of Columbia on behalf of the National Wildlife Federation, Florida Wildlife Federation and the Apalachicola Riverkeeper claiming the Army Corps failed to properly protect the tri-state ecosystem in the development of its revised manual dictating the control of water flow. The manual was last updated in 1958.

For decades, Florida, Georgia and Alabama have been at odds over how much fresh water is allowed to flow downstream from north Georgia to the Apalachicola Bay. A lack of freshwater has imperiled the Apalachicola River and its namesake bay, wrecking havoc on the area’s fragile environment and coastal community economies.

In February, a U.S. Supreme Court-appointed special master sided with Georgia in a 2013 lawsuit filed by Florida alleging the Peach State diverted too much water from the river system, damaging Apalachicola Bay and along with it the Franklin County seafood industry.

Thursday’s lawsuit, however, focuses on the most recent revision to the Army Corps master plan, which the lawsuit says could continue to starve Apalachicola Bay. It asks the court to order the Army Corps to revise the plan to address what it says are violations of several federal environmental laws.

“The bottom line is that the Army Corps is failing to protect one of the most significant ecosystems in the Western hemisphere,” said Melissa Samet, senior water resources counsel for NWF, in a statement. “We have the ability and the responsibility to save this amazing treasure and the vast array of fish and wildlife that rely on it. The Army Corps can lead the way, but only if they comply with the law.”

Environmental impact statements were not sufficient, wildlife and fish were not considered and conservation overlooked the lawsuit claims.

In addition to further imperiling wildlife along the watershed, the Army Corps’ plan has a widespread impact on people.

“The Army Corps’ mismanagement continues to threaten the livelihoods of thousands of Floridians as well as the Apalachicola River and Bay – an ecosystem of international significance that supports fisheries worth billions of dollars to Florida,” said Apalachicola Riverkeeper Dan Tonsmeire. “Federal regulators need to address the ecological issues that are affecting communities in our three states. With this lawsuit, we hope to restore a level playing field that considers the ecosystem functions that are critical to meet the human needs for all involved.”

Contact Karl Etters at [email protected] or @KarlEtters on Twitter.