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Emergent Sandbar Habitat (ESH)
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This Project Implementation Report (PIR) focuses on potential ESH projects located at Missouri River Miles (RM) 789.7, 759.4 and 756.7.
In accordance with the recommendations of the USFWS found in the RPA of the 2003 BiOp Amendment, the Corps is proposing to restore three ESH
complexes to support the Interior Least Tern (endangered) and the Piping Plover (threatened) in the 59-Mile Segment of the MNRR. The
locations were selected and projects collaboratively designed by staff from the Corps, USFWS, NPS, South Dakota Game, Fish and Parks (SDGFP),
and Nebraska Game and Parks Commission (NGPC).
An electronic version of the document can be found below or under MRRP Documents, Recent Articles/Reports. Comments are due by May 25, 2010.
Instructions on providing comments are inside the cover page of the document.
PIR/EA for ESH Complexes in the Missouri River
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| The purpose of the ESH Program is to mechanically create quality sandbar habitat for two federally listed species of birds, the least tern and
piping plover. Habitat quantity goals are established for the program in the 2003 Amended Biological Opinion on the Operation of the Missouri
River Mainstem System. The historic hydrograph of the Missouri River has been permanently altered as a result of the construction of the
six mainstem dams. Because the system is permanently altered, the historic flow regime that existed prior to construction of the dams has
changed dramatically. Prior to construction of the dams, the mountain snow melt and the plains snow melt would create two separate influxes of
water into the system each spring. These snow melt events coupled with spring rains would erode and deposit sand resulting in the creation of
barren sandbars. The least tern and piping plover prefer sparsely vegetated sandbars that are not connected to adjacent banks as nesting and
foraging habitat.
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| The U. S. Fish and Wildlife Service has established sandbar acreage goals for the
ESH Program. The following acreage goals need to be achieved by the year 2015:
below Garrison Dam - 50 acres of habitat per river mile; below Fort Randall Dam - 20
acres per mile; Lewis & Clark Lake - 80 acres per mile; and below Gavins Point Dam - 80 acres per river mile.
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| The Emergent Sandbar Habitat Program had 175 acres of new nesting and foraging habitat available for the birds during the 2009
nesting season. The new habitat was constructed between September 2008 and April of 2009 at river miles 795, 774, and 827 in Lewis &
Clark Lake and below Gavins Point Dam. Contracts have been awarded to construct 87 acres of habitat in the fall of 2009 and the spring
of 2010 at river miles 781, 781.4 and 842. Water levels in the Missouri River Mainstem system allowed a more normal flow regime out of
Gavins Point Dam in 2009 than in recent years. The increased releases covered shallowly submerged sand that was previously exposed under
lower flow scenarios. In 2009 most of the available tern and plover habitat was a result of the Corps' ESH construction program.
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Sandbars can be created and maintained by mechanically building new areas, clearing existing sandbars of vegetation or modifying
river flows during the year. To balance habitat restoration with the river's other uses, the U.S. Army Corps of Engineers (Corps) is
currently using construction methods rather than manipulating river flow levels.
To construct new sandbars, methodologies vary for each project location depending on site conditions and the chosen contractor's
construction methodology preferences. Various combinations of dredging and/or heavy equipment such as backhoes, draglines, bulldozers,
and scrapers are utilized to construct the sandbar to specified contours and elevations. The construction season for ESH projects is
short as it is limited to the times of year when the birds are not in the area and weather conditions allow. Birds typically arrive
in mid April and leave in mid to late August. The ESH Program has contractors ready to begin work as soon as the birds leave the area
in the summer.
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ESH Construction at river mile 774
Two bulldozers shape dredged material at ESH construction project at river mile 774. The newly created sandbar
complex added 49 acres of habitat for the terns and plovers in 2009 below Gavins Point Dam.
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Vegetation removal
Vegetation removal on existing sandbars also creates habitat.
Oftentimes birds will abandon sandbars where there is too much vegetation. A study is currently
being conducted to determine the most effective vegetation control methodology. The photo features
one of the many test plots currently on the Missouri River to test combinations of pre and post
emergent herbicides, mowing, and overtopping methodologies. Preliminary results will be available
in the fall of 2010. After the most successful methodology is identified, an emphasis will be
placed on reclaiming some sandbars that have been overtaken by vegetation throughout the Missouri
River from Garrision Dam to Ponca, Nebraska.
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Multi-agency team
When choosing potential ESH construction sites, a multi-agency
team meets each year to review maps and to get out on the river to look at potential sites.
Shown here are representatives from the Corps and the National Park Service. U. S. Fish
and Wildlife Service, as well representatives from the states of North Dakota and South Dakota
and Nebraska, also participate in these planning sessions each year.
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