Diversion Inlet Structure


The Diversion Inlet Structure near Horace, North Dakota, is one of three gated control structures on the southern embankment of the Fargo-Moorhead (FM) Area Diversion Project. The U.S. Army Corps of Engineers awarded the contracts to build all three structures to Ames Construction.

The FM Area Diversion Project will protect 230,000 people and 70 square miles of infrastructure from catastrophic flooding by limiting the flow of floodwaters into the metro area and diverting floodwater into a 30-mile-long bypass channel.

Ames began inlet construction by using material excavated from the bypass channel to construct earthen dams. Two embankments were constructed on top of thousands of wick drains installed in the underlying soils to expedite soil consolidation and limit the amount of settlement.

Concrete work formed the foundation for the massive Tainter gates, the radial arm floodgates that control the flow of water. Ames hit major milestones in 2022 with the delivery, assemblage, and installation of the gates. Crews also installed 44 cast-in-place deck panels that will serve as the service bridges over the dam walls.

With completion of the service bridges, electrical controls, painting, coatings, and final turf establishment, the Diversion Inlet was complete by the end of the 2023 construction season.

Learn more:
Metro Flood Diversion Authority

Markets: Federal, Water Resources, Canals

Location: Horace, North Dakota

Completion: December 2023

Project Owner: U.S. Army Corps of Engineers


  • Deep soil improvements
  • Structural concrete


  • Installed 3 Tainter gates. Each gate is 26 feet high and 50 feet wide.
  • Excavated 264,000 cubic yards of material.
  • Installed 55,400 linear feet of steel piling to support the structure.
  • Poured 11,700 cubic yards of concrete.
  • Placed 20,000 cubic yards of riprap.

2023 Recognition of Special Achievement
National Academy of Construction

2022 Gold Award
Bridge/Water Structure Category
North Dakota Ready-Mix & Concrete Products Association

2021 Dan W. Renfro Partnering Award
Mississippi Valley Associated General Contractors