Advocacy organizations, residents and representatives of American Indian tribes are seeking to block construction of a new streetcar line that would run along North Rampart Street and St. Claude Avenue by filing a lawsuit that says local and federal agencies did not conduct studies needed to show the project would not harm historic landmarks or create environmental issues.

The suit was filed in federal court on Monday, the same day crews began preparing for construction on the line, which will run from Canal Street to Elysian Fields Avenue. It seeks to block the Regional Transit Authority from continuing work on the project until those studies are carried out.

“This will give everybody a chance to make all their complaints,” said Jack Stewart, with Bring Our Streetcars Home, one of the groups suing to stop the project.

The suit is based on federal regulations that say studies dealing with the preservation of historic artifacts and properties, sites of importance to Indian tribes and the environment must be conducted before a project that uses federal money can move forward.

Without those studies, the suit says, the streetcar project could threaten “a wealth of historical treasures including ancient forts, city walls, culturally and religiously significant artifacts and grave sites.” It also could lead to flooding in the area, the suit says.

“This project has been talked about now since about 2007 or 2008, and the same things were being ignored all along,” said Stewart, who lives near the Loyola Avenue streetcar line that was criticized for problems during its construction. “They could have addressed them. No one likes to sue anybody.”

Plaintiffs in the suit include Bring Our Streetcars Home, a group that sought to return historic New Orleans streetcars to the city in the 1990s; the People’s Institute for Survival and Beyond, an anti-racism organization; several residents who live near the planned North Rampart line; and representatives of the Choctaw Houma and Choctaw Mowo Band tribes.

The RTA and the private company that manages its operations, Transdev, are listed as defendants along with the U.S. Department of Transportation and the Federal Emergency Management Agency.

The RTA and Transdev had no comment on the lawsuit, spokeswoman Patrice Bell Mercadel said.

The Rampart line has been controversial since its details were unveiled in 2013. Transit advocates have argued the project should have included dedicated lanes for the streetcar tracks, rather than have them share lanes with cars and other vehicles. Nearby residents raised a wide variety of concerns about the project and its construction at a hearing last week, arguing that it could create problems for businesses and historic properties.

Mercedes Whitecloud, one of the plaintiffs in the suit, said she asked Transdev officials whether the studies listed in the suit had been conducted and was told they were not necessary because federal money is not involved in the project.

The $41.5 million, 1.6-mile project is being funded through a 2010 bond sale by the RTA. However, the suit says the project is based on studies that were paid for with federal money and two of the streetcars that will be used for the route were purchased for the Canal Street line with federal money and refurbished with more federal dollars after Hurricane Katrina.

The suit also argues the federally mandated reviews are necessary because of the large amount of federal money that goes to the RTA as a whole.

“This will cause a series of public hearings where they go back and actually invite everybody,” said Stewart, who said the RTA has ignored residents’ concerns and complaints as the process has moved along. “And they’ll have to actually listen because it will be done before a federal group.”

Follow Jeff Adelson on Twitter, @jadelson.