The International Boundary and Water Commission concluded last month that Fisher Industries, which built a privately funded border fence near Mission, failed to comply with a 1970 treaty between the United States and Mexico.

After conducting a complex hydraulic analysis, the United States Section of the IBWC — a binational government agency that handles border issues, including the diversion of water from the Rio Grande and the physical location of the U.S.-Mexico border — notified North Dakota-based Fisher Industries about the conclusion in a letter dated April 20.

“From our analyses, we noted that the constructed bollard fence is not in compliance with the 1970 Boundary Treaty,” according to the letter. “Specifically, we identified one location where the percent deflection was 10.32%, well in excess of the threshold limit of +5%.”

Attorneys for the federal government, which filed a lawsuit against Fisher Industries in December, and the company discussed the letter during a court hearing Wednesday morning.

Fisher Industries started building the approximately 3-mile-long fence last year without approval from the IBWC. The approval process requires an application, hydraulic modeling and consultation with the Mexican section of the IBWC.

The federal government filed the lawsuit on Dec. 5, concerned that unapproved construction in the floodplain could alter the course of the Rio Grande — and, as a result, the location of the border itself.

The IBWC analysis, however, may actually be good news for Fisher Industries.

A hydraulic analysis conducted by Fisher Industries identified four potentially problematic deflection points, said Assistant U.S. Attorney Eric Paxton Warner, who represents the government. The IBWC analysis found just one.

“I think this could work out,” Warner said during the hearing.

Attorney Mark Courtois, who represents Fisher Industries, said the company didn’t necessarily agree with the IBWC analysis.

“I think it’s the engineers that need to get together and work that out,” Courtois said.

U.S. District Judge Randy Crane agreed to schedule a status conference in 60 days. In the meantime, the IBWC and Fisher Industries will review the hydraulic analysis.

In the April 20 letter, the IBWC suggested Fisher Industries may be able to reduce water deflection by adding gates to the fence, shifting the location of the fence or removing vegetation from the floodplain.

Courtois, the attorney for Fisher Industries, said the company plans to add gates anyway to accommodate Border Patrol. The number of gates and where they would be located remains undetermined.

“Once we get those marching orders and are all on the same page, we’ll go in and do what we need to do,” Courtois said.

Warner and Courtois sounded cautiously optimistic that engineers could work out any remaining problems.

Engineers with the United States section of the IBWC also sent hydraulic models to their counterparts in Mexico, who may offer comments or objections.

“They are the wild card,” Warner said during the hearing. “Because they will run the model and analyze it themselves.”

Crane, the federal judge, also held a status conference Wednesday in a related lawsuit filed by the North American Butterfly Association, which vehemently opposes the privately funded border fence.

The hydraulic model appears to show very few issues, Crane said.

Attorney Javier Peña, who represents the butterfly association, said his client wanted to independently review the hydraulic model.

The butterfly association remains concerned about how the model attempts to represent the fence. During a flood, vegetation could press against the fence and stop water from flowing between the bollards. That may cause the fence to collapse or gradually change the course of the Rio Grande.

“We’d like to see it for ourselves,” Peña said, adding that how the model accounted for the impact of the fence, which is a series of bollards with spaces between them, is important. “Just to confirm that.”