2013 afs lessons learned
- 1. Restoration Lessons Learned From a Fish Hugger & River Nerd David Bidelspach James Vincent
- 2. Restoration Lessons Learned • #1 – Develop a Process Based Restoration • Matrix for Key Species • #2 – Energy/Heat Dissipation • Un-uniform Energy Dissipation will limit the fishery • #3 - Central Tendency of a River • This is not subjective; understand fluvial geomorphology • #4 – Floodplain Interactions • Don’t let the fishery be Imparted by Channel Incision and Poor Floodplain Function • #5 – Regional Curves and Mini-Regional Curves • Trying to provide habitat improvements without the proper channel dimension is like a “Love Grenade”. You are lovingly trying to help the fishery but it is just going to blow up in your face
- 3. #1 – Develop a Process Based Restoration • Process based design is a design that is targeted to increase the function of a process to meet the goals and objectives of a project. Paraphrase from Dr. Palmer June 2nd
- 4. #2 – Uniform Energy/Heat Dissipation • Uniform Energy Dissipation vs. Large Energy Dissipation Structures – Longitudinal Profile concavity – Profile Slope should decrease with flow – Transition between energy states or maintenance • Pool- Pool Spacing – Existing conditions as a boundary based on reach stability and confinement – Central tendency and effective discharge • Width to Depth Ratio – Thermal Heat Transfer
- 5. AS-BUILTLONG PRO vs. PRE CONDITION LONG PRO CH WS BKF P1 P2 P3 P4 ExistingBasedon As-built Elevation(ft) Distancealongstream(ft) 940 942 944 946 948 950 952 954 956 958 960 962 964 966 968 970 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 XS5-ASBUILT XS6-ASBUILT XS3-ASBUILT XS2-ASBUILT
- 6. Non- Uniform Energy Dissipation
- 7. Add Water
- 8. #3 - Central Tendency of the River • The answers are in the River • Use current technology to document existing morphology – Scour lines – Deposition - Bar Formation – Bankfull Features when appropriate – Pool-Pool spacing – Reference Parameters and Reference Reach
- 12. Matrix Channel Incision – High WDR - Vegetation and Sediment Transport
- 13. Channel Incision – High WDR - Vegetation and Sediment Transport
- 14. # 4 Floodplain Interactions - Incision • Choice of Design Flow and Flow Regimes – Don’t limit the design to the Bankfull flow • (~ 1.2yr event in NC) – Design up to an acceptable risk level with multiple flows • (1.01 Low- Flow, 1.2yr Bankfull, 2yr, 5 yr, 25yr, 100 yr) • Convergence and Divergence of all Design Flows – Change in velocity and sediment transport competency and capacity due to convergence and divergence of flow could lead to critical flow and a hydraulic jump • ( 10:1 Horizontal transition) • (100:1 vertical from the channel slope) • Turning of Design Flows – Increase of Shear Stress based on radius of curvature is not limited to the bankfull channel • (2* W Min radius of curvature for any design flow)
- 15. Saamis Coulee Medicine Hat , Alberta - Choice of Design Flow and Flow Regimes
- 16. Floodplain Interactions and Function
- 17. Channel Incision – High WDR - Vegetation and Sediment Transport
- 18. # 5 Mini- Regional Curves • A mini- regional curves within the disturbed watershed can be used as a design tool more appropriately than a standard bankfull regional curve • A mini-regional curve based on area can be done for any project and should be to help quantify design uncertainty • Create regional curves on bankfull, Inner-berm, TOB and other depositional features when available • Published regional curves should be used as a comparison not as a design tool • Discuss regional and mini-regional curves with friends
- 20. Bankfull y = 18.762x0.6239 R2 = 0.9738 Inner Berm y = 8.7236x0.6359 R2 = 0.9578 ALL TOB WITH SANDY DEP y = 54.17x0.4879 R2 = 0.8556 TOB 45% - 65% Imp y = 68.465x0.6289 R2 = 0.9861 TOB 25% - 45% y = 45.515x0.6292 R2 = 0.9358 TOB 10% - 25% y = 37.299x0.6137 R2 = 0.9933 1.0 10.0 100.0 1000.0 10000.0 0.1 1.0 10.0 100.0 1000.0 Cross-ASectionalArea(sqft)
- 21. Restoration Fundamentals • The answers are in the river • Are we fighting the central tendency? • This is not a subjective • What is the geomorphic potential? • Design sustainability • Floodplain Interactions • Don’t let the fishery be limited by Channel Incision and Poor Floodplain Function