Stream and Watershed Restoration - a Guide to Restoring Riverine Processes and Habitats

List of Contributors, xi Foreword, xiii Series Foreword, xv Preface, xvi 1 Introduction to Restoration: Key Steps for Designing Effective Programs and Projects, 1 1.1 Introduction, 1 1.2 What is restoration?, 2 1.3 Why is restoration needed?, 3 1.4 History of the environmental movement, 4 1.5 History of stream and watershed restoration, 5 1.6 Key steps for planning and implementing restoration, 7 1.7 References, 8 2 Watershed Processes, Human Impacts, and Process-based Restoration, 11 2.1 Introduction, 11 2.2 The hierarchical structure of watersheds and riverine ecosystems, 13 2.3 The landscape template and biogeography, 17 2.4 Watershed-scale processes, 18 2.4.1 Runoff and stream flow, 18 2.4.2 Erosion and sediment supply, 20 2.4.3 Nutrients, 22 2.5 Reach-scale processes, 22 2.5.1 Riparian processes, 22 2.5.2 Fluvial processes: Stream flow and flood storage, 26 2.5.3 Fluvial processes: Sediment transport and storage, 27 2.5.4 Channel and floodplain dynamics, 28 2.5.5 Organic matter transport and storage, 29 2.5.6 Instream biological processes, 29 2.6 Common alterations to watershed processes and functions, 31 2.6.1 Alteration of watershed-scale processes, 31 2.6.2 Alteration of reach-scale processes, 34 2.6.3 Direct manipulation of ecosystem features, 35 2.7 Process-based restoration, 35 2.7.1 Process-based principles for restoration, 36 2.7.2 Applying the principles to restoration, 37 2.8 Summary, 40 2.9 References, 40 3 Watershed Assessments and Identification of Restoration Needs, 50 3.1 Introduction, 50 3.2 The role of restoration goals in guiding watershed assessments, 51 3.2.1 Stating restoration goals, 52 3.2.2 Designing the watershed assessment to refl ect restoration goals and local geography, 53 3.3 Assessing causes of habitat and biological degradation, 56 3.3.1 Use of landscape and river classifi cation to understand the watershed template, 57 3.3.2 Assessing watershed-scale (non-point) processes, 61 3.3.2.1 Sediment supply: Erosion and delivery to streams, 61 3.3.2.2 Hydrology: Runoff and stream fl ow, 63 3.3.2.3 Nutrients and pollutants, 68 3.3.3 Assessing reach-scale processes, 70 3.3.3.1 Riparian processes, 70 3.3.3.2 Floodplain processes, 73 3.3.3.3 Fluvial processes and conditions, 73 3.4 Assessing habitat alteration, 79 3.4.1 Habitat type and quantity, 79 3.4.2 Water quality, 84 3.5 Assessing changes in biota, 86 3.5.1 Single-species assessment, 86 3.5.2 Multi-species assessment, 89 3.6 Assessing potential effects of climate change, 91 3.7 Identifying restoration opportunities, 93 3.7.1 Summarize the watershed assessment results and identify restoration actions, 93 3.7.2 Develop a restoration strategy, 94 3.7.3 Summarize constraints on restoration opportunities, 95 3.7.4 Climate change considerations, 96 3.8 Case studies, 96 3.8.1 Skagit River, Washington State, USA, 96 3.8.2 River Eden, England, UK, 100 3.9 Summary, 103 3.10 References, 104 4 The Human Dimensions of Stream Restoration: Working with Diverse Partners to Develop and Implement Restoration, 114 4.1 Introduction, 114 4.2 Setting the stage: Socio-political geography of stream restoration, 116 4.2.1 Nature of the challenge, 116 4.2.2 Understanding property and property rights, 116 4.2.3 Landscapes of restoration, 117 4.2.4 Understanding landowner/manager and agency objectives, 120 4.2.5 Why understanding socio-political geography is important, 121 4.3 How stream restoration becomes accepted, 122 4.3.1 Restoration as innovation, 123 4.3.2 Innovation diffusion through networks, 123 4.3.3 Process of innovation adoption, 123 4.3.4 Innovation acceptance, 124 4.3.5 Why understanding innovation diffusion is important, 125 4.4 Organizations and the behaviors and motivations of those who work for them, 125 4.4.1 Organizational behaviors and motivations, 126 4.4.1.1 Motivations of offi cials, 126 4.4.1.2 Leveraging organizational behaviors, 126 4.4.2 Understanding your own and other organizations, 127 4.4.3 Why understanding organizational patterns is important, 129 4.5 Approaches to elicit cooperation, 132 4.5.1 Institutions to support stream restoration, 132 4.5.2 Techniques to engage landowners, 133 4.5.3 Achieving agreement with project partners, 136 4.5.3.1 The Prisoner s Dilemma, 136 4.5.3.2 Guidelines to build and maintain cooperation, 136 4.5.4 Why understanding cooperation is important, 138 4.6 Moving forward: Further reading in human dimensions of stream restoration, 139 4.6.1 Collective action, 139 4.6.2 Social capital and the triple bottom line, 139 4.6.3 Environmental justice, 140 4.6.4 Resilience, 140 4.7 Summary, 140 4.8 References, 141 5 Selecting Appropriate Stream and Watershed Restoration Techniques, 144 5.1 Introduction, 144 5.1.1 Common categories of techniques, 144 5.1.2 Selecting the appropriate technique: What process or habitat will be restored or improved?, 146 5.2 Connectivity, 147 5.2.1 Longitudinal connectivity, 147 5.2.1.1 Dam removal and modifi cation, 147 5.2.1.2 Culvert and stream-crossing removal, replacement or modification, 149 5.2.1.3 Fish passage structures, 151 5.2.2 Techniques to restore lateral connectivity and fl oodplain function, 152 5.2.2.1 Levee removal or setbacks, 152 5.2.2.2 Reconnecting isolated fl oodplain wetlands, sloughs, and other habitats, 153 5.3 Sediment and hydrology, 154 5.3.1 Reducing sediment and hydrologic impacts of roads, 154 5.3.1.1 Forest and unpaved road removal and restoration, 154 5.3.1.2 Road improvements, 155 5.3.1.3 Reducing or eliminating impacts of paved roads and impervious surfaces, 157 5.3.2 Reducing sediment and pollutants from agricultural lands, 158 5.3.3 Increasing sediment supply, retention and aggrading incised channels, 160 5.3.4 Increasing instream flows and fl ood pulses, 160 5.4 Riparian restoration strategies, 161 5.4.1 Silviculture techniques, 161 5.4.1.1 Planting, 161 5.4.1.2 Thinning to promote tree and vegetation growth, 164 5.4.1.3 Removal of exotic and invasive species, 164 5.4.2 Fencing and grazing reduction, 165 5.4.3 Riparian buffers and protection, 167 5.5 Habitat improvement and creation techniques, 167 5.5.1 Instream habitat improvement techniques, 167 5.5.1.1 Structures to create pools, riffles, and cover and improve complexity, 168 5.5.1.2 Gravel addition and creation of spawning habitat, 171 5.5.1.3 Recreating meanders, 171 5.5.2 Creation of floodplain habitats, 172 5.5.3 When are habitat improvement techniques appropriate?, 173 5.6 Miscellaneous restoration techniques, 173 5.6.1 Beaver restoration or control, 174 5.6.2 Bank stabilization, 174 5.6.3 Nutrient additions, 175 5.6.4 Vegetation management, 176 5.6.5 Other factors to consider when selecting restoration techniques, 177 5.7 Summary, 178 5.8 References, 179 6 Prioritization of Watersheds and Restoration Projects, 189 6.1 Introduction, 189 6.2 Determine overall goals and scale, 190 6.2.1 Legal frameworks, funding, and goals, 192 6.2.2 Spatial and temporal scale, 192 6.3 Who will prioritize projects? Selecting the team, 194 6.4 Prioritization approaches and criteria, 194 6.4.1 Common prioritization strategies, 195 6.4.1.1 Prioritizing restoration actions by project type, 195 6.4.1.2 Refugia, 195 6.4.1.3 Habitat area and increase in fish or other biota, 199 6.4.1.4 Capacity and life-cycle models for prioritizing habitats, 199 6.4.1.5 Costs, cost-effectiveness, and cost-benefit analysis, 201 6.4.1.6 Conservation planning software and computer models, 203 6.4.1.7 Scoring and multi-criteria decision analysis, 204 6.4.2 Selecting a prioritization approach, 206 6.5 Completing analyses and examining rankings, 207 6.6 Summary, 210 6.7 References, 210 7 Developing, Designing, and Implementing Restoration Projects, 215 7.1 Introduction, 215 7.2 Identify the problem, 217 7.3 Assess project context, 218 7.4 Define project goals and objectives, 219 7.5 Investigative analysis, 221 7.5.1 Investigative analyses for in-channel restoration projects, 221 7.5.1.1 Maps and surveys, 221 7.5.1.2 Hydrologic investigation, 223 7.5.1.3 Hydraulic modeling, 227 7.5.1.4 Sediment transport analysis, 230 7.5.1.5 Geomorphic investigation, 231 7.5.1.6 Geotechnical assessment, 232 7.5.1.7 Uncertainty and risk, 233 7.5.2 Investigative analyses for other restoration actions, 234 7.6 Evaluate alternatives, 235 7.7 Project design, 236 7.7.1 Design approaches, 237 7.7.2 Specify project elements that will meet project objectives, 238 7.7.3 Establish design criteria for project elements that define expectations, 238 7.7.4 Develop design details to meet criteria for each element, 239 7.7.5 Verify that elements address project objectives, 239 7.7.6 Communicating project design, 239 7.7.6.1 Design reports, 240 7.7.6.2 Plans and specifi cations, 240 7.8 Implementation, 241 7.9 Monitoring, 242 7.10 Case studies, 242 7.10.1 Removal of the Number 1 Dam, Chichiawan River, Taiwan, 243 7.10.2 Bridge Creek riparian restoration, 245 7.10.3 Fisher Slough Restoration, Skagit River, Washington, USA, 245 7.11 Summary, 248 7.12 References, 249 8 Monitoring and Evaluation of Restoration Actions, 254 8.1 Introduction, 254 8.2 What is monitoring and evaluation?, 255 8.3 Steps for developing an M&E program, 256 8.3.1 Defining restoration goals and monitoring objectives, 256 8.3.2 Defining questions, hypotheses, and spatial scale, 257 8.3.2.1 Defining the spatial scale, 259 8.3.3 Selecting the monitoring design, 260 8.3.3.1 Treatments, controls, and references, 260 8.3.3.2 Before-after and before-after control-impact designs, 261 8.3.3.3 Post-treatment designs, 261 8.3.3.4 Which design is most appropriate?, 263 8.3.4 Parameters: Determining what to monitor, 264 8.3.5 Determining how many sites or years to monitor, 269 8.3.6 Sampling scheme, 272 8.4 Guidelines for analyzing and summarizing data, 273 8.5 Monitoring of multiple restoration actions at a watershed scale, 273 8.6 Implementation: Design is not enough, 274 8.7 Summary, 275 8.8 References, 276 9 Synthesis: Developing Comprehensive Restoration Programs, 280 9.1 Introduction, 280 9.2 Components of a comprehensive restoration program, 280 9.2.1 Goals, assessments, and identifying restoration actions, 282 9.2.2 Prioritizing restoration actions or watersheds, 282 9.2.3 Selecting restoration techniques and designing restoration actions, 282 9.2.4 Monitoring, 283 9.2.5 Examples of bringing the components together, 284 9.3 Developing proposals and evaluating projects for funding or permitting, 286 9.4 Moving from opportunistic to strategic restoration, 287 9.5 Conclusions, 289 9.6 References, 289 Index, 290 See Colour plate Section between 160 161