Emergent Sandbar Habitat Program Middle Missouri River

Transcription

1 Emergent Sandbar Habitat Program Middle Missouri River Jeremiah Szynskie, P.E. Hydrologic Engineering Branch

2 Introduction Main Stem System Dam Closures Fort Peck 1937 Fort Randall 1952 Garrison Gavins Point Oahe Big Bend June 1967 Pools at or near normal operating levels and the six dams operating as 1 system

3 Missouri River Main Stem System MAINSTEM STATS 811 river miles below Gavins Point Dam to the mouth at St Louis, MO. The first 59 river miles below Gavins Point Dam are semi natural. About 325 miles of open river water remain between the dams, when the reservoirs are near normal operating levels. Multi-Purpose Pool miles with a water surface of about 1,000,000 acres.

4 Missouri River Main Stem System Purposes MAINSTEM STATS Flood Control Navigation Irrigation Power Production Water Supply Water Quality Control Recreation Fish and Wildlife Benefits

5 Changes to Historic Missouri River System MAINSTEM STATS Prior to the dams approximately 135 million tons of sediment was transported by the river as suspended load. Today the sediment passing through the system is virtually zero. Profound changes to the Missouri River flows. The mean annual discharge has not changed much over time, but high and low flows have changed dramatically.

6 Missouri River Basin Runoff Above Sioux City NWD - Reservoir Control Center Summary of 2006 Actual Regulation

7 Missouri River Basin Runoff Above Sioux City NWD - Reservoir Control Center Summary of 2006 Actual Regulation

8 How has the Main Stem System Affected Sandbars? MAINSTEM STATS The dams ability to trap sediment reduces sediment in downstream reaches for deposition Reduction in peak discharges has reduced the variability in heights of new sandbars Existing sandbars do not get inundated so vegetation grows and prevents birds from nesting.

9 Sandbar Vegetation River Mile 841 River Mile 781

10 Least Tern and Piping Plover ESH = Emergent Sandbar Habitat Endangered Interior Least Tern and Threatened Piping Plover Interior Least Tern (Sterna antillarum) Piping Plover (Charadrius melodus) Emergent Sandbar Habitat Program

11 Purpose - ESH Compliance with the Missouri River Biological Opinion (BiOp) issued by the Fish and Wildlife Service (FWS) Avoid jeopardizing the Least tern and Piping plover Part of the larger Missouri River Recovery effort; also includes the Bald Eagle (Cottonwood Habitat) and Pallid Sturgeon (Shallow Water Habitat) Emergent Sandbar Habitat Program

12 What is the ESH program trying to accomplish? MAISTEM STATS To mechanically construct and maintain quality, inter-channel habitat, with little to no vegetation cover, for the use of Least Terns and Piping Plovers.

13 History of the ESH Program 1985: Interior Least Tern and Piping Plover Federally Listed 1989: Corps enters consultation with FWS over Master Manual Revision 1990: First BiOp is issued 1990: Pallid Sturgeon Federally Listed 1990 s: Initial ESH work is started. Includes sandbar construction on a relatively small scale 2000: New BiOp issued that includes the Pallid 2003: BiOp Amendment issued 2004: Larger scale ESH projects started in the river channel : Reservoir sandbar project under construction Emergent Sandbar Habitat Program

14 Characteristics of ESH Bare Sand: Provides ideal nesting habitat preferred by birds Inter-channel: dynamic environment Wetted Perimeter: Habitat for insects, the food source of Piping Plovers River Mile 770, 73 acres, Constructed Winter 2005 Emergent Sandbar Habitat Program

15 Characteristics of ESH - Continued Nesting Habitat: Should be at least 3 acres, the ideal being roughly 10 acres. Located high and dry on the U/S side of individual sandbars. Area should be relatively level with small undulations 0.5 to 1.5 in height. Well draining particles ranging in size from fine sand to stones < 1 in. in diameter Foraging/Brood Rearing Habitat: Area should be approximately three times larger than the nesting habitat Must be connected to the nesting habitat Slopes to water should be 1:25 and not exceed 1:10. Emergent Sandbar Habitat Program

16 Various Methods in Creating ESH Create sandbars from off-channel or in-channel materials Vegetation removal with or without reshaping sandbars -Mechanical or chemical Create sandbars in reservoirs Emergent Sandbar Habitat Program

17 ESH Project Locations Emergent Sandbar Habitat Program

18 ESH and Floodplain Restoration First explored during construction of the Ponca Project Use dredged material from backwaters, side channels to build upon submerged bars Benefits: Fish Habitat Tern forage areas Adds sediment, nutrients to the river Backwater / ESH Restoration - Ponca State Park, NE Emergent Sandbar Habitat Program

19 ESH constructed using material in the river River Mile 761.4, Constructed Fall 2004 Emergent Sandbar Habitat Program

20 ESH constructed using material in the river Main Channel has been along the Nebraska side for many years Missouri River River Mile 760, ,000cfs, Constructed Fall 2004 Emergent Sandbar Habitat Program

21 ESH constructed using material in the river Main Channel has been along the South Dakota side for many years Missouri River River Mile 777, 74 25,000 cfs, currently under construction Emergent Sandbar Habitat Program

22 Reservoir Habitat Shorelines used by plovers when the reservoirs are down Some island creation projects Provides increased longevity compared in-channel sites Cultural Resource Protection, Recreation Benefits Fish Gut Island, Lake Oahe Sedimentation Delta, Lewis and Clark Lake Emergent Sandbar Habitat Program

23 Lewis & Clark Lake

24 Off-channel areas Could provide off-channel ESH habitat in an area not overly beneficial to wildlife or for recreation Increased longevity

25 Bazile Creek WMA Multiple Benefits: Sandbar Habitat Deep water areas for fish over wintering Increased access for noxious weed control Increased connection to the river Recreation opportunities

26 2008 ESH Projects River Mile 848

27 2008 ESH Projects River Mile 842

28 2008 ESH Projects River Mile 838

29 2008 ESH Projects River Mile 795

30 ESH Site Nest Locations Yellow Boxes Piping Plovers Red Triangles Least Terns Emergent Sandbar Habitat Program

31 ESH Site Nest Locations Yellow Boxes Piping Plovers Red Triangles - Terns Emergent Sandbar Habitat Program

32 The Future Continue to build different types of projects and apply lessons learned Work with partner agencies and identify projects with multiple benefits Missouri River at the Chief Standing Bear Memorial Bridge, River Mile 841 Emergent Sandbar Habitat Program

33 Questions? Emergent Sandbar Habitat Program