FARGO, N.D. (AP) — Opponents and proponents of a planned Red River diversion project around Fargo and Moorhead, Minnesota say they’re happy to have a chance to lay out their positions in front of a judge.

The $2 billion channel is designed to move water around the flood-prone Fargo metropolitan area, but would need a staging area south of the city to store water in times of serious flooding.  A group representing about 20 upstream cities and townships in North Dakota and Minnesota filed a federal lawsuit in August 2013 asking the U.S. Army Corps of Engineers to come up with a cheaper project that doesn’t flood farmland.

A hearing is scheduled today in Minneapolis to discuss whether the corps followed proper protocol when it designed the 36-mile channel. Tim Fox, the Wilkin County, Minnesota, state’s attorney who has been involved in litigation against the diversion, said it’s a significant event because the issue has been bounced around between state and federal courts without much oral argument.

“This is the actually the first time where the substantive elements of our complaint are going to be heard by the court,” Fox said Sunday. “Everything prior to this time has been mostly procedural.”

Keith Berndt, the Cass County administrator and member of the Fargo-Moorhead Diversion Authority, said diversion backers also welcome the hearing.

“I think it has been too long in coming,” Berndt said Sunday. “It seems to me that the folks who don’t like the project have been throwing whatever they can at the wall to see if it sticks. I’m glad we are finally at this point.”

The Richland/Wilkin Joint Powers Authority, which filed the original lawsuit, has said in court documents that the corps violated the National Environmental Policy Act, or NEPA, by not considering upstream impacts. The corps says it fulfilled NEPA requirements by evaluating five other diversion alternatives, working with the Minnesota Department of Natural Resources and other agencies on an environmental impact study, and modifying the plan based on complaints primarily from the state of Minnesota.

There will be no witnesses at Monday’s hearing. Robert Cattanach, an attorney representing the diversion authority, said U.S. District Judge John Tunheim’s ruling on the case could take a few months because of the volume of evidence. He also said the losing party could file an appeal to the 8th U.S. Circuit Court of Appeals.