Topic 9: Natural Channel Design

Transcription

1 Topic 9: Natural Channel Design

2 Course Schedule Field trip to White Dam (Mar 30) Cars v. van Reading assignments (Stay tuned!) Environmental Practicum Report American Rivers Dam Removal Guide Conceptual modeling paper? Leaders: Kyle (and Justin) Need to finalize schedule Dam removal and fish passage (Apr 6) Field trip (Apr 13) Stormwater tour? NCD project? DRAFT WRITING ASSIGNMENT DUE Environmental flow management (Apr 20) Last class (Apr 27) FINAL WRITING ASSIGNMENT DUE Large wood? Watershed management practices? Course summary, big ideas, or outlining a review paper? Panel reviews of writing assignment

3 Why is stream classification useful? Focus to a group of aquatic ecosystems that function similarly Reduce the level of natural variability that must be considered Identify and assesses common functions most likely to be performed Simplify and improve the precision in the development of models Reduce the amount of data that must be collected and analyzed Promote stratified systematic or random sampling. Establish surrogate or proxy metrics Expedite and reduce the cost of study From Bruce Pruitt

4 Function Form v. Function Original / Restored Degraded Structure After Bradshaw (1996)

5 Function-based Classification Systems Channel Evolution Model Montgomery and Buffington Schumm

6 Rosgen Stream Classification Multi-level classification Specific to hydrophysiographic provinces Ten phases in the design process (i.e., Natural Channel Design) Basic premise: the stable shape of the channel (i.e., form) is predictable and restoration should target this condition

7 Level I

8 Level II

9 Reference reaches as blueprints: Natural Channel Design Rosgen (2006)

10 Fighters to your corners Natural Channel Design Dave Rosgen Richard Hey Will Harman Greg Jennings North Carolina team States Practitioners Academic Critics Andy Simon Matt Kondolf Doug Shields Martin Doyle Kyle Juracek Faith Fitzpatrick Margaret Palmer Emily Bernhardt

11 Strong supporters, but are these statements overly optimistic?

12 2015 Course Schedule (15 people / course ~ $300k) Level Description Registration Cost I II III IV V Applied fluvial geomorphology Asheville, NC Sheperdstown, WV Seeley Lake, MT Fayetteville, AR River morphology and applications Asheville, NC Sheperdstown, WV Bend, OR River assessment and monitoring Sheperdstown, WV Grand Tanghee Resort, WY River restoration and natural channel design Duluth, MN River restoration design implementation None scheduled

13 Key Points of Contention Short courses v. academic training Practical utility v. peer review Opportunity cost of applying Rosgen s methods Broad-scale adoption (and sometimes requirement) Science-y challenges: Form v. function in classification Bed v. bank material Snapshot in time Predictive capacity Reference conditions must have similar drainage area

14 Items that get passed over Availability of reference blueprints Are there any stated goals for this form of restoration? Is this stream restoration or simply channel stability? Is this useful for communication? Tool for a time past? Is this simply the best of what s around? 25 Physiographic provinces X 41 Level II Stream Types X 2 hydraulic geometry relations per province (rural and urban) 1 = 2050 stream types and hydraulic geometry curves 1 Doll et al. (2002, 2003) 14

15 Interesting Reading Background Malakoff The river doctor. Science. Lave The Controversy Over Natural Channel Design: Substantive Explanations and Potential Avenues for Resolution. JAWRA 45 (6): Lave Fields and Streams: Stream Restoration, Neoliberalism, and the Future of Environmental Science. UGA Press. Natural Channel Design Rosgen Natural channel design: Fundamental concepts, assumptions, and methods. In Stream Restoration in Dynamics Fluvial Systems (Eds. Simon, Bennett, and Castro). Hey Fluvial Geomorphological Methodology for Natural Stable Channel Design. JAWRA, 42 (2): Rosgen, D.L., A Classification of Natural Rivers. Catena 22: Critiques Juracek and Fitzpatrick Limitations and implications of stream classification. JAWRA, 39 (3): Gillilan, S., Use and Misuse of Channel Classification Schemes. Stream Notes, October 1996, Stream Systems Technology Center, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Center, Fort Collins, Colorado. Savery, T. S., G. H. Belt, and D. A. Higgins, Evaluation of the Rosgen Stream Classification System in Chequamegon-Nicolet National Forest, Wisconsin. JAWRA 37 (3): Roper, Brett B., John M. Buffington, Eric Archer, Chris Moyer, and Mike Ward, The Role of Observer Variation in Determining Rosgen Stream Types in Northeastern Oregon Mountain Streams. JAWRA 44 (2):