Science on the Sandy River: Where is all the (Marmot) Dam sediment? Part II

Transcription

1 Science on the Sandy River: Where is all the (Marmot) Dam sediment? Part II Johns Hopkins University National Center for Earth-surface Dynamics (NCED) Graham Matthews & Associates (GMA)

2 Introduction Russ Plaeger Sandy River Basin Watershed Council Dr. Peter Wilcock Johns Hopkins University

3 Overview Introduction Russ Plaeger Sandy River Basin Watershed Council Dr. Peter Wilcock Johns Hopkins University Chuck Podolak Johns Hopkins University Smokey Pittman Graham Matthews and Associates Why we are measuring What Where Water year summary Water year 2009 Above the gorge Below the gorge What s next Bottom Line big flow year, much data still to be collected, minimum major changes below the gorge

4 Who are we? Johns Hopkins / NCED / GMA / SRBWC USGS USFS OSU PSU Bureau of Reclamation Others: multiple undergraduate research projects and more Assisted by: PGE Landowners

5 Why we are measuring Goal: Where does the Marmot Dam sediment go, and how does it affect the bed of the Sandy? Why? Pools / Riffles / Eddies = fish habitat & migration paths Pools / Eddies / Bars = recreation spots & boating routes River bed changes can influence flooding patterns

6 What we are measuring Bed at rest (summer)

7 What we are measuring Bed in motion (winter)

8 Where we are measuring Studies concentrate on intensely measuring several sites, not entire river

9 Big Picture Water Year 2008

10 Preliminary WY 2009 Bed in motion (winter) Bedload at Brightwood for WY2008 appears to have been about 22% of the load measured below the gorge 36,000 tons vs 160,000 tons Samples collected above the dam (in WY2009) are composed of 60-70% sand, while samples below the former damsite (collected in WY2008) were composed of 85-90% sand

11 WY Several very large flows this winter

12 Preliminary WY 2009 Bed at rest (summer) Downstream of dam

13 Preliminary WY 2009 Bed at rest (summer) Still very active during large storms Upstream of gorge July 9, 2008

14 Preliminary WY 2009 Bed at rest (summer) Still very active during large storms Upstream of gorge Nov 17, 2008

15 Preliminary WY 2009 Bed at rest (summer) Still very active during large storms Upstream of gorge Jan 10, 2009

16 Preliminary WY 2009 Bed at rest (summer) Still very active during large storms Upstream of gorge July 8, 2009

17 Preliminary WY 2009 Bed at rest (summer) Still very active during large storms Upstream of gorge July 9, 2008

18 Preliminary WY 2009 Bed at rest (summer) Upstream of gorge July 2007 July 2009

19 Preliminary WY 2009 Bed at rest (summer) Downstream of gorge fs (2ft) BI MI UI Total D50 gravel (2ft) BI MI UI Total

20 Preliminary WY 2009 July 2007 Bed at rest (summer) Downstream of gorge July 2008 July 2009

21 Preliminary WY 2009 Oxbow Park near Gordon Creek Photo: fall banks 2008 banks 2009 banks

22 Preliminary WY 2009 Oxbow Park near Gordon Creek Photo: fall banks

23 Near the dam So what? large amount of deposition still shifting seems normal for the Sandy Revenue area some small changes in bars and texture no massive changes hard to distinguish between effects of dam removal versus large storms Downstream (Dodge, Oxbow, Dabney, etc ) sand moving through but what s different dynamic but is it Marmot related?

24 What s Next GMA survey July 2009 DEA / PGE survey Sediment sampling winter JHU/NCED/GMA July 2010 Ongoing USGS / PSU work upstream

25 Acknowledgements Field Assistants: Daniela Martinez, Viviano Berrios, Ramsey Coronado, Carl Ekstrand, Michaela Long, Dajana Jurk, Cecilia Palomo, Katie Trifone, Kim Devillier, Tim Shin, Kimber Cooks, Diana Di Leonardo, Kiernan Folz Donahue, Gabriel Richarde, Jessica Roark, Kristen Sweeney Rose Wallick, Jon Major, Mackenzie Keith, Charlie Cannon, Rachael Peavler, Rebecca Collins USGS Gordon Grant OSU/USFS Connie Athman - USFS Dave Heintzman, John Esler, Tony Dentel, Tim Keller - PGE Bill Doran Metro Parks Greg Stewart, Barbara Burkholder Funding National Center for Earth Surface Dynamics US Forest Service Oregon Watershed Enhancement Board

26 For More files/podolak_marmot_dam_project.html Chuck Podolak, Johns Hopkins (208) Russ Plaeger, Sandy River Basin Watershed Council (503) Smokey Pittman, Graham Matthews & Associates (530)