Ponca State Park Habitat Restoration Project
By Luke Wallace
U.S. Army Corps of Engineers
A sandbar complex constructed by the U.S. Army Corps of Engineers (Corps) at Ponca State Park last year was one of the most successful breeding areas for interior least terns on the Missouri River in 2004.
Ponca State Park is located at the downstream end of the 59-mile segment of the Missouri National Recreational River near Ponca. This stretch of the river includes stretches of the Missouri River between Gavins Point Dam in South Dakota , and Ponca State Park . This is one of the last remaining unchannelized portions of the Missouri River .
In 1999, the Nebraska Game and Parks Commission (NGPC) asked for help from the Corps to study and construct a habitat restoration project at Ponca State Park on 295 acres of adjacent river bottomland that was donated to the park.
This land consisted of a series of side channels, a backwater and farmed wetlands that had degraded due to land-use practices and hydrology and sediment transport changes that have occurred in the Missouri River primarily as a result of building Gavins Point Dam .
The Corps hired Tetra Tech, Inc. to develop a restoration plan with an integrated environmental assessment and a 90 percent design for the proposed restoration alternative. This design was developed in cooperation with the NGPC, the National Park Service in O'Neill and the U.S. Fish and Wildlife Service (USFWS) in Grand Island .
The project goal was to restore degraded aquatic habitat areas. Plans and specifications were completed last March.
Final design included a series of backwaters and wetlands attached to the Missouri River , tallgrass prairie restoration in the formerly farmed areas and using dredged sandy spoil material from the backwaters to create emergent sandbar habitat for endangered interior least terns, and threatened piping plovers.
A $2.34 million construction contract went to Western Contracting Corp. last April and construction began in April. All major excavation work was completed in June 2004.
Spoil material was discharged into the Missouri River to create emergent sandbar habitat. About 533,240 cubic yards of sandy material was excavated to create wetlands and backwaters. This material was discharged into the river for this purpose.
In total, the project created 29 acres of backwater habitat, 17.5 acres of wetland, three emergent sandbars of 37 combined acres and 36 acres of tallgrass prairie.
Least terns began using the first constructed sandbar while it was still being built. Immediately after construction, waterfowl, shorebirds, five species of turtles and a variety of other wildlife were using the backwaters.
More than 3,900 fish representing 36 different species were collected from the backwaters last summer and fall.
Twenty-three piping plovers and 64 interior least terns hatched and were successfully fledged from the constructed emergent sandbar island complex, making them the most productive sandbar islands on the Missouri River for interior least terns last year.
