Construction of the Fish Passage Project at Lock and Dam 22 on the Mississippi River has progressed steadily since it began last May.
According to USACE, crews are nearing completion of the final two weirs in the rock ramp, making the fish passage structure fully visible for the first – and last – time before it becomes submerged under water when the project is finished.
“ This is a rare opportunity to see the first structure of its kind in the Mississippi River before it becomes part of the future river ecosystem ,” said Ty Jones , contracting officer representative for the project. “It’s been great seeing the project go from a drawing on paper, to a digital rendering, to a miniature model, and now to full-scale construction.”
Once the weirs are finished, the contractor J.F. Brennan Company will complete the remaining rock access berms that stabilize the ramp and weirs.
Concrete placement for the sill and downstream floor slabs in the intake structure is ongoing, and scaffolding has been installed along the underside of the dam to facilitate conduit placement. Much of the electrical work on the Missouri side of the project is complete, and fabrication of mooring dolphins and bulkheads is underway, with final shipments scheduled later this year.
The fish passage structure, located on the spillway portion of the dam, extends downstream into the tailwater area and is designed to reconnect fragmented river habitats. The structure will allow fish to move upstream to river and tributary areas that became limited when the lock and dam was constructed in the 1930s.
USACE said that the goal of this reconnection is to increase the size and distribution of migratory fish populations.