Fargo, North Dakota: Crews Finish Digging the 30-Mile Fargo-Moorhead Diversion Channel

Construction crews have finished excavating the 30-mile stormwater diversion channel for the Fargo-Moorhead Area Diversion, the Metro Flood Diversion Authority said in its October construction update for Fargo, North Dakota.

The digging moved 45 million cubic yards of material. The authority put that in local terms: enough to fill the Fargodome 21 times. The channel is the centerpiece of the flood protection project being built by the authority with the U.S. Army Corps of Engineers and the Red River Valley Alliance, and finishing its excavation is the project's biggest earthmoving milestone.

The work that continues along the channel

Digging is done, but the corridor is still an active construction site. ASN Constructors, the contractor building the channel, continues to install security fencing along it and to place topsoil and mulch.

The authority said the last portion of Reach SE-3 of the 22-mile southern embankment reached full height this month. Crews have begun placing topsoil and turf reinforcement matting on that stretch. The earthen levee will hold back floodwater when the diversion operates during a flood.

Aqueducts and mitigation work

Work also continued on the project's two aqueducts, the structures where local rivers cross over the diversion channel. At the Sheyenne River Aqueduct, crews excavated the spillway approach channel, where excess river flows discharge over the spillway crest, down its drop structure and into the diversion channel. They finished installing the metal cladding around the vertical lift gate support structure, moved on to flashing and trim, and drove ice-retention piling that will keep large sheets of ice from reaching and blocking the structure's flume.

Mitigation work continues across the project footprint. At Clara Cemetery, one of eight cemeteries being mitigated, the contractor worked on a ring levee to protect it.

How the project got here

In its September update, the authority reported that 44.2 million of the 45 million cubic yards had been excavated and only the channel plug excavation remained. That same update said Reach 1B of the southern embankment now connects the Diversion Inlet Structure with the adjacent reaches, and that crews had planted 18,000 of the 25,000 trees planned along the project. The October update closes out the excavation count and turns the channel work toward finishing touches, fencing and seeding.