Background:
Decision support tools are created and used to guide outreach, inform planning, analyze and prioritize information and facilitate decision-making. Partnership members are interested in developing interactive tools that provide a flexible and systematic approach for identifying priority tide gate project sites from a multitude of perspectives.
The tools can be used by funders, local governments, restoration partners, and others to evaluate project sites at a local, regional or coast-wide scale for a variety of potential outcomes. Examples of outcomes that Partnership members are interested in achieving include agricultural land protection, economic development benefits, community benefits, flood reduction, community resiliency, infrastructure improvements, water quality, ecosystem function, and fish habitat. For each of these outcomes to be considered, relevant data must be available and incorporated into the tools, and the tools must be built-in in a manner that allows additional data to be added as it becomes available.
Actions:
Beginning in 2016, The Nature Conservancy (TNC) developed and piloted an optimization model in the Coquille River that spatially pinpoints which tide gates in a basin to replace based upon their estimated replacement cost and the potential habitat gains for Coho salmon after passage through the tide gate is improved. The model also identifies stream culverts for replacement or removal to provide unrestricted passage for salmon to their spawning grounds.
Following the pilot project, the approach was expanded to Coos Bay, and additional fish species were added. Reports describing the model and its outputs for both the Coquille and Coos Bay were released in 2018. TNC is now deploying the tool in other watersheds throughout the Oregon Coast. In 2020, the Nature Conservancy received a grant from the Oregon Watershed Enhancement Board (OWEB) to explore adding agriculture, infrastructure, and other economic parameters to the tool as well as considerations such as sea-level rise. TNC issued a survey to 250 stakeholders to query the role of tide gates in their work, the types of decisions they make related to tide gates, and factors they consider when evaluating tide gate replacements. TNC then followed up with key respondents – agencies, non-governmental organizations, the agriculture industry, and others – to further explore their responses and data availability.
In addition, the Oregon Department of Fish and Wildlife (ODFW) is developing a probabilistic graphical model, known as a Bayesian Belief network, that looks a fish habitat quality and other parameters. TNC is actively working with ODFW to integrate the agency’s work into the multi-objective optimization tool.
Progress and Next Steps:
TNC will continue to evaluate model enhancements and solutions and plans to submit its final report to OWEB and the Partnership in summer 2021. ODFW also intends to complete its Bayesian model in 2021. Additional information will be announced by the Partnership as progress is made including the final report and upcoming training sessions for the Partnership and others to learn more about the decision support tool.