Prepared in cooperation with the University of Washington and the Lower Columbia River Estuary Partnership Columbia River Estuary Ecosystem Classification— Concept and Application Open-File Report 2011–1228 U.S. Department of the Interior U.S. Geological Survey Cover: Photograph showing view of lower Columbia River estuary, approximately 55 km from the mouth, looking down-estuary with Welch Island in the foreground; the ocean entrance in the background. Photograph taken by Charles Simenstad, University of Washington, May 26, 2005. Columbia River Estuary Ecosystem Classification— Concept and Application By Charles A. Simenstad and Jennifer L. Burke, University of Washington; Jim E. O’Connor and Charles Cannon, U.S. Geological Survey; Danelle W. Heatwole and Mary F. Ramirez, University of Washington; Ian R. Waite and Timothy D. Counihan, U.S. Geological Survey; and Krista L. Jones, Lower Columbia River Estuary Partnership Prepared in cooperation with the University of Washington and the Lower Columbia River Estuary Partnership Open-File Report 2011-1228 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2011 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Suggested citation: Simenstad, C.A., Burke, J.L., O’Connor, J.E., Cannon, C., Heatwole, D.W., Ramirez, M.F., Waite, I.R., Counihan, T.D., and Jones, K.L., 2011, Columbia River Estuary Ecosystem Classification—Concept and Application: U.S. Geological Survey Open-File Report 2011-1228, 54 p. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted material contained within this report. Contents Executive Summary ....................................................................................................................................................... 1 Introduction .................................................................................................................................................................... 2 Impetus for New Estuarine Ecosystem Classification ................................................................................................ 3 Objectives .................................................................................................................................................................. 6 Approach ....................................................................................................................................................................... 6 Columbia River Estuary, Processes and Ecosystems ................................................................................................ 6 Setting of the Columbia River Basin and Estuary ................................................................................................... 7 Contemporary Hydrologic and Geomorphic Processes and Landforms ................................................................. 8 Floods and Tides ................................................................................................................................................ 8 Sediment Movement and Transfers .................................................................................................................... 9 Design of Columbia River Estuary Ecosystem Classification ....................................................................................11 Methods ........................................................................................................................................................................12 Data Criteria and Requirements ................................................................................................................................12 Primary Criteria for Classification Design ..............................................................................................................12 Secondary .............................................................................................................................................................12 GIS Structure ............................................................................................................................................................13 Base Data and Analytical Steps ................................................................................................................................13 Historical Flood Plain and Tidal Extent ..................................................................................................................13 Level-Specific Data Sources .................................................................................................................................13 Levels 1 and 2— Ecosystem Province and Ecoregion ......................................................................................13 Level 3—Hydrogeomorphic Reach ....................................................................................................................14 Level 4—Ecosystem Complex ...........................................................................................................................15 Level 5—Geomorphic Catena............................................................................................................................16 Level 6—Primary Cover Class ...........................................................................................................................17 Results ..........................................................................................................................................................................18 Level 1—Ecosystem Province ..................................................................................................................................18 Level 2—Ecoregion ...................................................................................................................................................18 Level 3—Hydrogeomorphic Reach ...........................................................................................................................18 Level 4—Ecosystem Complex ..................................................................................................................................22 Level 5—Geomorphic Catena ...................................................................................................................................23 Level 6—Primary Cover Class ..................................................................................................................................23 Discussion ....................................................................................................................................................................24 General and Unique Applicability to Estuarine Classification Needs .........................................................................24 Utility and Application to Estuarine Science, Monitoring, Restoration and Management ..........................................24 Research ...............................................................................................................................................................25 Change Analyses ..................................................................................................................................................25 Monitoring .............................................................................................................................................................26 Restoration and Preservation Planning .................................................................................................................27 Management .........................................................................................................................................................27 Constraints on Data Adequacy and Application of the Classification to the Entire Columbia River Estuary .............28 Validation Needs .......................................................................................................................................................29 Summary and Recommendations.................................................................................................................................29 Acknowledgments ........................................................................................................................................................30 References Cited ..........................................................................................................................................................30 iii Appendix A. Summary of location, geographic and geomorphic setting, major landforms, geologic content and history, characteristic geomorphic and hydrologic processes, and anthropogenic factors affecting key processes in eight Hydrogeomorphic Reach forming the Columbia River Estuary