Session C1 - Applying the Stream Functions Pyramid to Geomorphic Assessments and Restoration Design

Transcription

1 University of Massachusetts - Amherst ScholarWorks@UMass Amherst International Conference on Engineering and Ecohydrology for Fish Passage International Conference on Engineering and Ecohydrology for Fish Passage 2012 Jun 5th, 11:30 AM - 12:00 PM Session C1 - Applying the Stream Functions Pyramid to Geomorphic Assessments and Restoration Design Will Harman Stream Mechanics Follow this and additional works at: Harman, Will, "Session C1 - Applying the Stream Functions Pyramid to Geomorphic Assessments and Restoration Design" (2012). International Conference on Engineering and Ecohydrology for Fish Passage This Event is brought to you for free and open access by the The Fish Passage Community at UMass Amherst at ScholarWorks@UMass Amherst. It has been accepted for inclusion in International Conference on Engineering and Ecohydrology for Fish Passage by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact scholarworks@library.umass.edu.

2 Applying the Stream Functions Pyramid to Geomorphic Assessments and Restoration Designs Will Harman, PG Stream Mechanics

3 Stream Functions Pyramid

4 Parameter Measurement Method Performance Standard No No No Sediment Transport Competency 1. Shear Stress Curve 2. Required Depth and Slope 3. Spreadsheets and Computer Models Sediment Transport Capacity 1. Computer Models 2. FLOWSED and POWERSED 3. BAGS Large Woody Debris Transport and Storage 1. Wohl et al. (2009) 2. Large Woody Debris Index Channel Evolution 1. Simon Channel Evolution Model 2. Rosgen Stream Type Succession Scenarios Too Much To Cover Bank Migration/Lateral Stability 1. Meander Width Ratio 2. BEHI / NBS 3. Bank Pins 4. Bank Profiles 5. Cross-Sectional Surveys 6. Bank Stability and Toe Erosion Model Riparian Vegetation 1. Buffer Width 2. Buffer Density 3. Buffer Composition 4. Buffer Age 5. Buffer Growth 6. Canopy Density 7. Proper Condition (PFC) 8. NRCS Stream Visual Assessment Protocol 9. Rapid Bioassessment Protocol 10. Watershed Assessment of River Stability and Sediment Supply (WARSSS) 11. USFWS Stream Assessment Ranking (SAR) Bed Form Diversity 1. Percent Riffle and Pool 2. Facet Slope 3. Pool-to-Pool Spacing 4. Depth Variability Bed Material Characterization 1. Bevenger and King (1995) 2. Riffle Stability Index (RSI) No No No No No

5 Focus of this Presentation Category Hydraulic Hydraulic Function-Based Parameter Floodplain Connectivity Flow Dynamics Geomorphology Bed Form Diversity Geomorphology Lateral Stability Bank Vegetation Measurement Method Bank Height Ratio and Entrenchment Ratio Pool-to-pool spacing Depth Variability

6 Restoration Potential The highest level of restoration that can be achieved, given the health of the watershed, results of the function-based assessment, and the project constraints.

7 Restoration 1 Healthy Watershed Reach Scale Restoration

8 Restoration 2 Impaired Watershed Reach Scale Restoration

9 Healthy Watershed + Reach Scale Restoration = Restoration 1 Levels 2-3 Levels 4-5 Impaired Watershed + Reach Scale Restoration = Restoration 2 Levels 2-3 Levels 2-3

10 Floodplain Connectivity Entrenchment Ratio (ER) ER = Floodprone Width / Bankfull Width Floodprone Width 2 X Bankfull Depth Bankfull Width Bank Height Ratio BHR = Height of Low Bank / Max Bankfull Depth Height of Low Bank Max Bankfull Depth

11 Great Floodplain Connectivity Source: Michael Baker Corporation

12 Floodplain Bench Source: Michael Baker Corporation

13 Floodplain Connectivity Performance Standards Metric -At- Risk Bank Height Ratio (BHR) Entrenchment Ratio (ER) for C and E Stream Types Entrenchment Ratio (ER) for B and Bc Stream Types 1.0 to to 1.5 > 1.5 > to 2.2 < 2.0 > to 1.4 < 1.2 Not

14 Rosgen, 1996 Bed Form Diversity

15 Sand bed forms Gravel/Cobble bed forms Step-pool bed forms Bed Form Types

16 Pool to Pool Spacing

17 Pool to Pool Spacing Performance Standards Measurement Method -at-risk Not Perennial Streams in Alluvial Valleys (C, E) Pool-to-Pool Spacing Ratio (Watersheds < 10 4 to 5 3 to 4 and 5 to 7 < 3.0 and >7.0 mi 2 ) Pool-to-Pool Spacing Ratio (Watersheds > 10 mi 2 ) 5 to and 7 to 8 < 3.5 and > 8 Moderate Gradient Perennial Streams in Colluvial Valleys Pool-to-Pool Spacing Ratio (Slope between 3 and 5%) 2 to 4 4 to 6 >6

18 Elevation(ft) Depth Variability text P P P P P Station (ft)

19 Depth Variability Performance Standards Measurement Method -at-risk Not Perennial Streams in Alluvial Valleys (C, E) Depth Variability Gravel Bed Streams (Pool Max Depth Ratio) Depth Variability Sand Bed Streams (Pool Max Depth Ratio) > to 1.5 <1.2 > to 1.2 <1.1 Moderate Gradient Perennial Streams in Colluvial Valleys Depth Variability (Pool Max Depth Ratio) > to 1.5 < 1.2

20 Using the Pyramid to show Functional Lift Level and Category Parameter Measurement Method Pre-Restoration Condition Post-Restoration Condition Value Rating Value Rating 1 - Hydrology Insert pre- and post restoration data 2 - Hydraulics 3 Geomorphology 4 Physiochemical Example Example Example Example Example Example Floodplain Connectivity Bank Height Ratio Entrenchment Ratio Not Not Biology

21 Channelized Streams Existing Condition Restored Condition Floodplain Connectivity

22 Channelized Stream Bed Form Diversity

23 Level and Category Parameter Measurement Method Pre-Restoration Condition Post-Restoration Condition Value Rating Value Rating 1 - Hydrology N/A 2 - Hydraulics Floodplain Connectivity Bank Height Ratio Entrenchment Ratio Not Not Geomorphology Bed Form Diversity Lateral Stability Pool-to-pool spacing Depth Variability BEHI/NBS >10 <1.1 High/High Not 4 to 5 Not >1.2 Not Low/Low Riparian Vegetation USFWS SAR No zones of vegetation represented Not All three zones represented

24 Level and Category Parameter Measurement Method Pre-Restoration Condition Post-Restoration Condition Value Rating Value Rating 4 - Physicochemical 5 Biology Water Quality Fish Communities Temperature Dissolved Oxygen Upstream / downstream monitoring Meets WQ stds. Not rep of ref cond. Meets WQ stds. Not rep of ref cond. Does not meet upstream reference condition -At- Risk -At- Risk Not Meets WQ stds. Meets ref condition Meets WQ stds. Meets ref condition Does meet upstream reference condition

25 Goal Restore project reach functions to meet upstream reference reach condition. Objectives Change the following Function-Based Parameters from Not- to Floodplain Connectivity Lateral Stability Riparian Vegetation Fish Communities Change the following Function-Based Parameters from -At-Risk to Temperature and Dissolved Oxygen

26 Headwater Mountain Streams Existing Condition Restored Condition

27 Elevation (ft) Mickey Reach Profile Chart TW LTOB RTOB WS RBKF LBKF Station (ft) Sample Reach 7 pools out of 3,300 feet of channel

28 2009 Photos

29 Pool to Pool Spacing / Bankfull Width and Total Number of Pools Year Min Max Total # > Existing Condition As-built Condition

30 Level and Category Parameter Measurement Method Pre-Restoration Condition Post-Restoration Condition Value Rating Value Rating 1 - Hydrology N/A 2 - Hydraulics Floodplain Connectivity Bank Height Ratio Entrenchment Ratio Geomorphology Bed Form Diversity Lateral Stability Pool-to-pool spacing Depth Variability BEHI/NBS > 6 <1.1 Moderate/ Low Not 2 to 4 Not >1.5 - At-Risk Low/Low Riparian Vegetation USFWS SAR No zones of vegetation represented Not All three zones represented

31 Level and Category Parameter Measurement Method Pre-Restoration Condition Post-Restoration Condition Value Rating Value Rating 4 - Physicochemical 5 Biology Water Quality Macroinvertebrates Fish Communities Temperature Dissolved Oxygen Upstream / downstream monitoring Upstream / downstream monitoring Meets WQ stds. Not rep of ref cond. Meets WQ stds. Not rep of ref cond. Does not meet upstream reference condition Does not meet upstream reference condition -At- Risk -At- Risk Not Not Meets WQ stds. Meets ref condition Meets WQ stds. Meets ref condition Does meet upstream reference condition Does meet upstream reference condition Don t Forget to use ph and Conductivity as a screening tool

32 Dam Removal When can we remove the dam and walk away versus having to include stream restoration? Source: Source: Michael Baker Corporation

33 Things to Look For Height and size of dam Size and quantity of sediment Recovery time Downstream impact Know why the dam is being removed. Source: Michael Baker Corporation

34 Key Function-Based Parameters Affected Category Level Level 5 - Biology Level 4 Physicochemical Level 3 - Geomorphology Level 2 - Hydraulics Level 1 - Hydrology Function-Based Parameter Fish Communities (Select specific species) Water Quality Sediment Transport, Lateral Stability, Bed Form Diversity, Riparian Vegetation Floodplain Connectivity, Flow Dynamics, Groundwater/Surface Water Exchange Flow Duration

35 Fish Passage

36 Key Function-Based Parameters Affected Category Level Level 5 - Biology Level 4 Physicochemical Level 3 - Geomorphology Level 2 - Hydraulics Level 1 - Hydrology Function-Based Parameter Fish Communities (Select specific species) Water Quality Sediment Transport, Lateral Stability, Bed Form Diversity, Riparian Vegetation Floodplain Connectivity, Flow Dynamics, Groundwater/Surface Water Exchange Flow Duration