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Structured Decision Making for Delta Smelt Demo Project

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Structured Decision Making for Delta Smelt Demo Project Structured Decision Making for Delta Smelt Demo Project Prepared for CSAMP/CAMT Project funded by State and Federal Water Contractors Prepared by Graham Long and Sally Rudd Compass Resource Management Ltd. 604.641.2875 Suite 210- 111 Water Street Vancouver, British Columbia Canada V6B 1A7 www.compassrm.com Date May 4, 2018 April 13th – reviewed by TWG and comments incorporated Table of Contents Table of Contents ............................................................................................................... i Executive Summary .......................................................................................................... iii Introduction ...................................................................................................................... 1 Approach .......................................................................................................................... 1 Problem Definition ........................................................................................................... 4 Objectives ......................................................................................................................... 5 Alternatives ...................................................................................................................... 9 Evaluation of Trade-offs ................................................................................................. 17 Discussion and Recommendations ................................................................................. 21 Process Reflections and Proposed Next Steps ............................................................... 23 References ...................................................................................................................... 27 Appendix 1 – Action Definitions ..................................................................................... 28 1 Aquatic Weed Control ....................................................................................... 29 2 North Delta Food Web Adaptive Management Projects .................................. 37 3 Outflow Augmentation in the Spring and Summer ........................................... 43 4 Reoperation of the Suisun Marsh Salinity Control Gates .................................. 58 5 Sediment Supplementation in the Low Salinity Zone ....................................... 64 6 Spawning Habitat Augmentation ...................................................................... 69 7 Roaring River Distribution System Food Production ......................................... 72 8 Coordinate Managed Wetland Flood and Drain Operations in Suisun Marsh 77 9 Adjust Fish Salvage Operations during Summer and Fall .................................. 83 10 Stormwater Discharge Management ................................................................ 86 11 Rio Vista Estuarine Research Station and Fish Technology Center ................... 91 12 Near-term Delta Smelt Habitat Restoration ...................................................... 96 i 13 Franks Tract Restoration Feasibility Study ...................................................... 106 Appendix 2 - The Rose Bioenergetics Model in support of a CAMT Structured Decision Making for Delta Smelt Demo Project ........................................................... 113 Appendix 3 – Cost Estimates ........................................................................................ 122 Appendix 4 - Qualitative Scoring for Ecological Objectives .......................................... 132 Glossary ........................................................................................................................ 148 Contacts for Actions ..................................................................................................... 149 ii Executive Summary This report documents a demonstration project undertaken during the summer/fall of 2017 to trial an application of structured decision making (SDM) techniques to the management of delta smelt in California’s Sacramento–San Joaquin Delta. Working closely with a Technical Working Group associated with the Collaborative Science and Adaptive Management Program (CSAMP), analysts from Compass Resource Management undertook a preliminary, multi-objective analysis of the 13 actions in the California Natural Resources Agency’s Delta Smelt Resiliency Strategy. The primary purpose of the analysis was to demonstrate the steps and processes that might be followed in the future to create a robust foundation for developing and evaluating actions undertaken in the Delta for delta smelt. The authors are not delta smelt experts but served to facilitate discussions among people with a broad understanding on the ecological, social and economic dimensions of the delta smelt management context. Over the course of several months, the group worked through the typical steps of a structured decision making process, including, clarifying the decision context; defining an objectives hierarchy and associated performance measures; developing alternatives; estimating consequences and evaluating trade-offs and preferences. As part of this work, for each of the 13 actions, a coarse-level influence diagram was developed, and major pathways of hypothesized cause and effect relationships described. ‘Full build-out’ cases for each action were defined to account for the discrepancy between different scales of application of actions specified in the Resiliency Strategy. A bioenergetics model was adapted to help predict the possible consequences for delta smelt of changes in physical parameters resulting from the actions. Structured expert judgment processes were followed to estimate other ecological impacts. A consequence table summarizing the predicted performance of each of the actions on the objectives was populated and the results used to reach tentative conclusions about the relative priority that might be shown to each of the 13 actions. While this demo project was a ‘first pass’ analysis of the Resiliency Strategy actions, the process was such that the TWG felt confident in providing preliminary recommendations based on what had been learned. Finally, this document presents a summary of recommendations about possible next steps and further work. iii Introduction Delta smelt (Hypomesus transpacificus) is a small fish endemic to the Sacramento–San Joaquin Delta in California that is on the verge of extinction (Moyle et al. 2018). In 2016, the California Natural Resources Agency released a Delta Smelt Resiliency Strategy that comprised 13 actions intended to improve the status of delta smelt (CNRA 2016). Although informed by the MAST Report and Conceptual Models (IEP 2015), the Resiliency Strategy does not attempt to assess the relative performance potential of the actions, aiming instead to be, “an aggressive approach to implementing any actions that can be implemented in the near term, can be implemented by the State with minimal involvement of other entities, and have the potential to benefit Delta Smelt”. As such, the 13 actions address different hypotheses that, individually or collectively, could affect the current status of the species. In general, actions for DS can be difficult to implement because of their typically high direct and indirect costs. This is partly due to the large spatial scale and associated resources required of almost any meaningful action and partly due, for those actions that require them, to the high economic value of alternative uses of water and land, as well as the large number of stakeholder groups involved. The Collaborative Science and Adaptive Management Program (CSAMP) is a multi-stakeholder policy and science advisory body that acts as a forum for discussion between regulatory agencies, non-governmental organizations (NGOs) and Public Water Authorities (PWAs). Its stated purpose is to act as a catalyst through which contentious and urgent management relevant science issues can be discussed and to compile and disseminate information for decision makers on contentious and urgent science issues (CSAMP, 2017). CSAMP has four groups of participants: 1) a Policy Group consisting of federal and state regulatory agency directors and top-level executives from relevant NGOs and PWAs; 2) A Collaborative Adaptive Management Team (CAMT) comprising managers and staff scientists that serve at the direction of the Policy Group; 3) Scoping Teams created on an as-needed basis to scope specific science studies; and 4) Investigators contracted to conduct studies. In early 2017, CSAMP discussed the potential use of a Structured Decision Making (SDM) process to support some of CSAMP’s immediate and longer-term discussions. As used here, SDM is an approach to deconstructing complex and controversial environmental management problems using techniques that help organize and separate technical uncertainties (which are a matter of science) from value-based judgments (which are a matter of policy). CSAMP decided to trial the use of SDM via a limited demonstration project, referred to as the SDM demo project. The purpose of the demo was to explore the potential application of SDM to issues of importance to CSAMP to better understand its potential future value to the organization. On behalf of CSAMP, in July 2017 the State and Federal Water Contractors hired Compass Resource Management Ltd of Vancouver, Canada to lead the demo project with technical and policy support from CSAMP members. Compass specializes in using SDM techniques
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