The Active River Area

April 2008 The Active River Area A Conservation Framework for Protecting Rivers and Streams ACKNOWLEDGEMENTS The authors wish to thank the following people whose thoughtful reviews, comments and other support helped to shape and inform this document. Special thanks go to Mike Kline (Vermont Agency of Natural Resources), Mark Anderson (TNC) and Jonathan Higgins (TNC), each of whom contributed significant ideas and information integral to the material we present. We would also like to thank Colin Apse, Michele DePhilip, Steve Haase, Kim Lutz, Jeff Opperman, Daryl Peterson, and Josh Royte for their often detailed comments at various times during the development of this report. Also, thank you to Charles Ferree (TNC) for support with the mod- eling, Rita Thanos (TNC) for tracking down the needed permissions and approvals, Jason Williams (MMI) for his illustration of the active river area components, and to Scott Hancock (Hancock Design) for designing this report. Finally, we want to acknowledge and thank the Sarah K. de Coizart Charitable Trust, without whose generous support this project would not have been possible. THE ACTIVE RIVER AREA A Conservation Framework for Protecting Rivers and Streams April 2008 This report was jointly prepared by Mark P. Smith (TNC), Roy Schiff (MMI), Arlene Olivero (TNC), and James MacBroom (MMI) The Nature Conservancy Eastern U.S. Freshwater Program 11 Avenue De Lafayette, 5th Floor Boston, MA 02111 USA www.nature.org Prepared with support from: Milone & MacBroom, Inc. 1233 Shelburne Road, Suite 150 South Burlington, Vermont 05403 Funding for this project provided by the Sarah K. de Coizart Charitable Trust I THE ACTIVE RIVER AREA A Conservation Framework for Protecting Rivers and Streams TABLE OF CONTENTS Chapter 1 Introduction . 1 The Active River Area as a Basis for Action . 1 Document Overview . 2 Chapter 2 Defining the Active River Area . 3 Linking Ecology and River Processes . 3 Components of the Active River Area. 4 Dominant Processes and Attributes. 6 Watershed Position . 10 Active River Area Components and Watershed Position . 11 Watersheds as a Nested Framework . 17 Chapter 3 Services from Functioning Active River Areas . 20 Other Habitat Values . 20 Avoidance and Reduction of Flood and Erosion Hazards . 21 Adapting to Climate Change . 22 Water Quality Protection . 22 Recreation Opportunities. 23 Open Space . 23 Chapter 4 Delineating the Active River Area . 25 Delineating the Active River Area . 25 Model Verification . 26 Case Study: Connecticut River Example. 27 Subwatershed and Reach Delineations . 29 Chapter 5 Assessing the Active River Area . 32 Stream Corridor Restoration. 32 Habitat Assessment . 33 Geomorphic Assessment. 34 Biomonitoring . 35 Chapter 6 Protecting River Processes . 37 Complementary to Other Freshwater Conservation Strategies . 37 Freshwater Conservation Planning. 38 Designing Freshwater Protected Area Networks . 38 Improving River Policies and Programs . 40 Chapter 7 Using Active River Area Concepts for Restoring River Processes . 42 Restoration of River and Active River Areas . 45 Stressor Identification . 45 Restoration Approaches . 45 Design Approaches . 46 Chapter 8 Conclusion . 48 Appendix A . 49 Citation Information: Smith, M.P., Schiff, R., Olivero, A. and MacBroom, J.G., 2008. THE ACTIVE RIVER AREA: A Conservation Framework for Protecting Rivers and Streams. The Nature Conservancy, Boston, MA. II THE ACTIVE RIVER AREA A Conservation Framework for Protecting Rivers and Streams CHAPTER 1: INTRODUCTION “Riparian corridors possess an unusually diverse array of species and environmental processes. This "ecological" diversity is related to variable flood regimes, geomorphic channel processes, altitudinal climate shifts, and upland influences on the fluvial corridor. This dynamic environment results in a variety of life history strategies, and a diversity of biogeochemical cycles and rates, as organisms adapt to disturbance regimes over broad spatio-temporal scales. These facts suggest that effective riparian management could ameliorate many ecological issues related to land use and environmental quality. We contend that riparian corridors should play an essential role in water and landscape planning, in the restoration of aquatic systems, and in catalyzing institutional and societal cooperation for these efforts.” (Naiman et al., 1993) Freshwater systems are among the most biologically diverse The active river area provides a systematic means for concep- and rich systems in the world (Decamps, 1997; Master et tualizing and protecting the river as a dynamic system with al., 1998). This richness and diversity is in large part a result a broad range of conditions that are typical of natural river of the highly dynamic nature of river systems which creates systems. The active river area is spatially explicit and can be a mosaic of shifting habitat types that vary in age, species readily identified – narrow in some areas, wider in others composition, and structure and provide a broad range of – and captures the living, dynamic processes and places natural conditions around which the life cycles of species that define these systems. The active river area includes a and natural communities have evolved (Ward et al., 2002). number of distinct components which provide specificity to guide actions for protection, restoration and manage- Since the rich and unique biodiversity values of rivers are ment (Figure 1.1). related to the dynamic nature of these systems, effective river conservation must include the protection of key The Active River Area as the Basis for Action physical and ecological processes. These processes are The understanding of the importance of riparian lands and driven in large.

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