1. Hydraulics of Engineered Log Jams Tessa Hanson

2. Background Tessa Hanson, Oregon State University22 August 2013 (fs.fed.us).

3. Research Question Fish Behavior with respect to Engineered Log Jams (ELJs). Tessa Hanson, Oregon State University22 August 2013 ( freshwatersillustrated.org).

4. My Research Drag force Calculate drag coefficient Shear stress distribution Calculate shear stress Map distribution over control volume Tessa Hanson, Oregon State University22 August 2013

5. Relevance Impact of log jams on hydraulic processes (shear stress, drag, etc.) Hydraulic processes  Geomorphic complexity (pools, riffles, etc.) Both geomorphic and hydraulic complexity affect habitat for aquatic species. Tessa Hanson, Oregon State University22 August 2013

6. Methods Data Collection Velocity: SonTek MicroADV (Acoustic Doppler Velocimeter) Devices Topography: Total Station Surveying Tessa Hanson, Oregon State University22 August 2013 (SonTek, 2008).

7. Methods Control Volume Defined by influence of ELJ, which corresponded to extent of velocity measurements. Tessa Hanson, Oregon State University22 August 2013

8. Methods Drag Coefficient Momentum extraction technique, where sum of forces equal to momentum flows Tessa Hanson, Oregon State University22 August 2013

9. Methods Force balance (equation) Balance in y-direction Balance in x-direction (Manners et al. 2006). Tessa Hanson, Oregon State University22 August 2013

10. Methods Shear Stress Distribution Create matrices of velocity data to analyze in Matlab. Given: Solve for and map in Matlab. Tessa Hanson, Oregon State University22 August 2013

11. Results/Conclusions Drag Coefficient High compared to that found in literature Possibility that control volume does not capture entire eddy at downstream. Shear Stress Distribution Matrices were not completed with all of necessary values. Tessa Hanson, Oregon State University22 August 2013

12. Recommendations Drag Coefficient Extend control volume. Recalculate shear using integral form. Shear Stress Distribution Finish matrices. Interpolate over 10 cm gaps to obtain finer spacing. Solve for and map in Matlab. Tessa Hanson, Oregon State University22 August 2013

13. References Manners, Rebecca B., M. W. Doyle, and M. J. Small. "Structure and Hydraulics of Natural Woody Debris Jams." Water Resources Research 43 (2006). SonTek. “15-MHz MicroADV expanded description.” YSI incorporate (2008). Tessa Hanson, Oregon State University22 August 2013

14. Questions? Thank-you to: Desirée Tullos Cara Walter Chad Higgins Will L’Hommedieu Julia Jones Peggy Lee Amanda Reinholtz Tessa Hanson, Oregon State University22 August 2013