What was once a flood control measure built by the U.S. Army Corps of Engineers (USACE) and authorized by the Flood Control Act of 1941, is now choking an area of the Neuse River that continues to threaten the migration of anadromous species of fish near Goldsboro, North Carolina. But there is a solution.
The Neuse River-Goldsboro Section 1135 Continuing Authorities Program (CAP) authorizes the USACE to initiate investigations and modify structures and operations of water resources projects constructed by the Corps to improve the quality of the environment, as long as the modifications are feasible, consistent with authorized project purposes, and will improve the quality of the environment in the public interest.
“If it’s determined that a USACE project contributed to the degradation of the quality of the environment, restoration measures may be implemented either at the project site or in other locations that have been affected by the project, subject to a determination that the restoration measures are not in conflict with authorized project purposes,” said USACE Wilmington District Community Planner Jason Glazener.
The main purpose of the Neuse River cutoff was to reduce agricultural flooding along a portion of the Neuse River main stem. Construction of the cutoff channel was completed in 1948, and included a low flow sheet pile weir near the upstream end of the channel. The weir has often been in a state of disrepair due to inadequate USACE funds to maintain it. The weir section was rebuilt in 1968 and 1983 due to deterioration and corrosion. In 2007, prompted by concerns that the degraded cutoff channel weir would breach and further reduce water depths and increase sedimentation in the main stem of the Neuse River where their primary water intake is located, the city of Goldsboro obtained the required approvals to repair the weir structure by placing rock stabilization along the upstream and downstream faces of the weir. However, the majority of the repair work conducted by the city washed out within a fairly short period of time after completion due to high-flow events.
“There’s a reduction in natural riverine function in the main stem of the Neuse River due to this federal project,” said Glazener. “Resource agencies and the non-federal sponsor city of Goldsboro are concerned that the current cutoff channel configuration creates a reduction in fish passage for anadromous fish species such as striped bass, American shad, blueback herring, American eel, and Atlantic sturgeon, the latter being a federally listed endangered species. These fish migrate upstream in search of suitable spawning habitat.”
The cutoff channel weir is located approximately 4,100 feet upstream of the confluence of the cutoff channel and the main stem of the Neuse River, Glazener explained. It is at this confluence that migrating fish decide which river reach to ascend. Under many flow conditions, both channels currently provide adequate depth and flow velocity to attract fish. Through personal communication with the city of Goldsboro, local fisherman have reported that the best fishing for striped bass and American shad, amongst others, is in the cutoff channel just below the weir. For fish enticed to ascend the cutoff channel, the weir acts as a barrier which obstructs passage upstream under all, but very high flow conditions. Common fish behavioral preference is to swim into the flow stream instead of back-tracking to search for alternative passage routes. Anadromous fish swimming up the cutoff channel would not reach upstream spawning and nursery habitats located at various spots up to 92 miles upstream. On April 17, biologists with the North Carolina Wildlife Resources Commission observed an eight-foot Atlantic sturgeon in the cutoff channel. The projects objective is to improve riverine functionality, to increase in flow volume, velocity and river level toward a more natural state. It also refers to improving fish migration access to upstream spawning habitats.
“The recommended plan consists of rebuilding the USACE weir to an elevation two-feet higher than the City of Goldsboro’s temporary weir, and three-feet higher than the original federal project weir. This would restore a portion of natural flow to the main stem of the river,” Glazener said. “The proposed steel sheet pile weir structure will be constructed approximately 25-feet downstream of the city’s existing temporary weir within the cutoff channel.