Final Willamette Coast & Middle Fork Literature Review with Figures
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Summary Report to Assist Development of Ecosystem Flow Recommendations for the Coast Fork and Middle Fork of the Willamette River, Oregon Stan Gregory 1, Linda Ashkenas 1, Chris Nygaard 2 Product of the Institute for Water and Watersheds Oregon State University Michael Campana, Director Prepared for Sustainable Rivers Project of The Nature Conservancy and the U.S. Army Corps of Engineers Project Officers: Leslie Bach (TNC) and Matt Rea (USACE) 1 Department of Fisheries & Wildlife, Oregon State University 2 USACE, Portland, OR 25 June 2007 TABLE OF CONTENTS Introduction Willamette River Flow Project.............................................................................................1 Goals and Objectives .........................................................................................................2 Summary Report Purpose ..................................................................................................3 Background Study Area Description.......................................................................................................5 Hydrologic Network and Discharge Regime .......................................................................6 Physical Processes and Conditions: Flow Requirements Water Quality .....................................................................................................................9 Temperature..................................................................................................................9 Nutrients and Toxic Pollutants .......................................................................................11 Sediment and Turbidity..................................................................................................12 Geomorphology and Floodplain Inundation ........................................................................14 Biological/Ecological Conditions: Flow Requirements .....................................................20 Terrestrial Vegetation .........................................................................................................20 Cottonwood and Willow .................................................................................................22 Ash, maple and alder.....................................................................................................23 Invasives .......................................................................................................................24 Terrestrial Vertebrates: Birds and Mammals.......................................................................28 Aquatic Invertebrates .........................................................................................................31 Short-lived species ........................................................................................................32 Long-lived species.........................................................................................................32 Aquatic Vertebrates............................................................................................................34 Amphibians and Reptiles...............................................................................................34 Western pond turtles ..............................................................................................34 Red-legged frog......................................................................................................35 Bullfrog ...................................................................................................................35 Fish ...............................................................................................................................38 Spring Chinook.......................................................................................................39 Lamprey .................................................................................................................40 Coastal cutthroat trout ............................................................................................41 Oregon chub...........................................................................................................41 Large-scale sucker .................................................................................................42 Large- and smallmouth bass...................................................................................43 Summary ................................................................................................................................47 Bibliography ..........................................................................................................................48 Tables .....................................................................................................................................58 Figures ...................................................................................................................................100 Appendices ............................................................................................................................199 ii List of Tables Table 1. Dams of the Coast and Middle Forks. Table 2. Water withdrawals presently under contract for irrigation (USACE 2000). Table 3a, Minimum flow requirements (in cfs) at Albany and Salem Table 3b: Volume of water required (in acre-feet) to meet minimum flow requirements at Albany and Salem. Table 4. Maximum flood flow releases (cfs) for normal flood control for all dams in the Willamette system. Table 5a. USGS gages on the Coast and Middle Forks and mainstem Willamette River used in this review. Table 5b. Draft flood frequency and magnitude under unregulated and regulated conditions for three gages: Middle Fork at Jasper, Coast Fork at Goshen, and Willamette River at Albany Table 6. Number of reaches listed as temperature impaired. Table 7. Summer temperature exceedence data summary for 303(d) listed segments in the Coast and Middle Fork Willamette. Table 8. Observed median seven-day rolling average temperatures downstream of USACE Coast and Middle Fork dams and monthly median seven-day rolling average of flow-weighted upstream tributary temperatures. Table 9. Target temperatures (in oC) by month for all USACE reservoirs in the Willamette basin. Table 10. Temperature criteria for 303(d) listed segments of river below USACE dams in the Coast and Middle Fork Willamette. Table 11. Seasonal Average OWQI Results for the Upper Willamette Basin (WY 1986 - 1995) Table 12: Revetments on Coast and Middle Fork Willamette subbasins. Table 13. Effects of flow and geomorphology on cottonwood stand patterns. Table 14. Mammals and birds of the Willamette River Basin. Table 15. Characteristics of freshwater mussels and most other macroinvertebrates. Table 16. Amphibian and reptile species of the Willamette Basin. iii Table 17. Fish species present in the Willamette River, modified for Coast and Middle Forks. Table 18. Species needs and impacts addressed by recent reviews and documents. Table 19. Minimum instream flow requirements and purposes below Coast and Middle Fork dams, including mainstem targets. Table 20. Flows needed for returning adult salmon to pass over dams. Table 21. Flows need for spawning by returning adult salmon. Table 22. Minimum incubation flows for anadromous salmonids. Table 23. “Redd protection flows”. Table 24. Minimum flows for rearing of all salmonids, including both anadromous and resident species. Table 25. Water temperature criteria for listed and sensitive fish species in the Coast and Middle Forks. Table 26. Summary of impacts of different flow regimes on ecosystem parameters and exemplar species. iv List of Figures Figure 1. Map of the Willamette River basin showing major tributaries and the locations of the thirteen USACE flood control projects. Figure 2 Subbasins of the Willamette River. Figure 3a and 3b: Coast Fork and Middle Fork drainage networks and topography. Figure 4. Coast and Middle Fork Geology. Figure 5a and b: Precipitation as rainfall. Figure 6: Precipitation as snowfall. Figure 7. Coast and Middle Forks drainage network with locations of USACE dams and USGS gages used in this report. Figure 8. Typical dam operation for flood control in the Willamette Basin. Figure 9. Observed flows at the Jasper Gage, Middle Fork Willamette River, 1935 – 2004. Months run from right to left to highlight peak flows. Figure 10. Observed flows at the Jasper Gage, Middle Fork Willamette River, 1935 – 2004. Months run from left to right to highlight summer low flows. Figure 11. Mean daily discharges (maxima, minima and averages) at the Jasper Gage, Middle Fork Willamette River…. Figure 12. Mean monthly discharges (maxima, minima and averages) at the Jasper Gage, Middle Fork Willamette River …….. Figure 13. Mean daily discharges (maxima, minima and averages) at the Jasper Gage, Middle Fork Willamette River for period of post-dam completion………. Figure 14. Mean monthly discharges (maxima, minima and averages) at the Jasper Gage, Middle Fork Willamette River for period of post-dam completion Figure 15. Annual peak discharges at the Jasper gage, Middle Fork of the Willamette River Figure 16. Draft flood frequency (exceedence curves) for the Middle Fork Willamette River at Jasper Figure 17. Flow duration curve for the Middle Fork Willamette River at Jasper Figure 18. Number of days discharges are at bankfull levels for the Middle Fork of the Willamette River at Jasper. v Figure 19. Mean daily flows for exemplar wet (1997) and dry (2001)