The City of Augusta, Ga., filed a complaint in South Carolina District Court against the U.S. Army Corps of Engineers and has requested that the state join it in opposing the demolition of the New Savannah Lock and Dam, which impacts water levels in the city.

On Oct. 29, the Corps of Engineers announced it will demolish the lock and dam and replace it with a rock weir fish passage that will lower the approximately 13-mile pool that keeps water levels high around downtown Augusta and North Augusta, according to the Augusta Chronicle. On Nov. 4, South Carolina Attorney General Alan Wilson filed a complaint.

The fish passage would allow endangered shortnose and Atlantic sturgeon and other migratory species access to spawning grounds at the Augusta Shoals, which have allegedly been blocked by the lock and dam since it began operating in 1937.

In the complaint, Augusta said the engineers failed to consider the effects of lowering the Savannah, including the river being the public water supply for the city and being a “cornerstone of its health and economic future.”

The city also said that the engineers didn’t consider the impact on Augusta parks, including the riverwalk and Augusta Canal National Heritage Area, as well as the impact on recreational events, including the Ironman triathlon and the Southern Nationals drag-boat race, which hasn’t been held in several years.

Following South Carolina’s lead, Augusta contends that the 2016 Water Infrastructure Improvements for the Nation Act requires the water levels to be kept as they were Dec. 16, 2016, at 114.5 feet. The same level was cited in 1930s easements granted as a condition for building the dam.

Construction of the weir passage requires a Navigable Waters Permit and a Clean Water Act permit. The Chronicle article said the suit alleges that the Corps of Engineers has not applied for them in either state and that it failed to follow National Environmental Policy Act requirements for projects that may significantly alter the environment.

“NEPA is the federal law that requires federal agencies take a hard look at the effects their projects will have,” Guy Quinn, an environmental consultant, told the Chronicle. “The South Carolina lawsuit is pretty light on this section, but the Augusta one lists dozens of factors the Corps failed to consider during its project studies.”

Augusta has asked the court for declarations that the Corps maintain the pool level at 114.5 feet and that the rock weir plan doesn’t comply with the WIIN act and seeks to permanently enjoin the Corps from moving forward with the plan.