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Home My WebLink About2024 03 02 Dosewallips River Collaborative DRAFT Meeting Summary2 1 Dosewallips River Collaborative DRAFT Meeting Summary Saturday, March 2, 2024 9:00 AM – 11:30 AM Hybrid Meeting Welcome and Introductions Attending: Tim Abbe (Natural Systems Design [NSD), Lisa Belleveau (Skokomish Tribe), Rebekah Brooks (Rebekah Brooks Contracting), Greg Brotherton (Jefferson County Commissioner), Lolinthea Hinckley (Jefferson County), Barb Jones (Jefferson County), Tressa Linquist (JCPH), Alicia Olivas (Hood Canal Coordinating Council), Tami Pokorny (Natural Resources Program Coordinator, JCPY), Dosewallips community landowners and members of the public Tami Pokorny welcomed the meeting attendees and gave an overview of the Dosewallips River Collaborative, an informal and inclusive discussion group focused on resiliency projects that Jefferson County Public Health is putting forward that will benefit salmon species and the community. This meeting would be immediately followed by site visits. More information on the Dosewallips River Project can be found at: https://www.co.jefferson.wa.us/1435/Dosewallips-River-Project. Public Comments There were no public comments. Additions to the Agenda There were no changes to the agenda. Approval of the Draft November Meeting Summary Delayed Announcements Tami Pokorny announced the site visits that would immediately follow this meeting. Parking and carpooling would be arranged after the meeting. Old Business Community Survey Update Delayed New Business New LiDAR and Change Detection for the Lower Dosewallips River Valley Tim Abbe of Natural Systems Design noted that a priority of these meetings was to hear from the public. At the next meeting, he hoped to be able to share hydraulic models and hear some ideas from the community on possible actions. Because the Federal Emergency Managing Agency (FEMA) maps are not always up to date, the new modeling results are intended to educate everyone about flood and erosion risks. Tim Abbe of Natural Systems Design then discussed the new 2023 green LiDAR (land and river bed topography) dataset for the lower valley and the relative elevation maps they’ve produced, which show 2 where elevation changes have occurred due to erosion, aggradation or other causes since the previous LiDAR was flown in 2019. There may be opportunities for wood installation projects in some areas that could reduce erosion and improve habitat for salmon. Tim reminded the group that any project ideas would be discussed with the community prior to development. Overview of Computer Modeling for Engineered Log Jams (ELJs) to Achieve Multiple Objectives Tim discussed the role of wood in rivers. In an interview with Ida and Vern Baily in May of 2005, they recalled that “There was a lot more [wood] than there is today. There used to be big logjams. When Mrs. Olson came here to homestead she walked across the river on a logjam [Brinnon Flat River Kilometer 1.5].” Wood creates habitat at different scales, and increases functions that are important to river ecology, including more physical complexity, habitat diversity, habitat quantity, biological productivity, flow attenuation, hyporheic exchange, and water quality. It can promote mature forests along terraces, provide a source for large wood into the future, increase stable hard points within the migration zone, slow channel migration, protect side channel habitat, slow terrace bank erosion, reduce property loss, protect terrace channel habitat, and create a more refined and complex channel. Wood is one part of the physical matter that enters stream networks. Just like inorganic sediment, wood can stay in place where it enters, or be transported downstream as either suspended or bedload. However, wood is unique from other sediment, in that it has different density, different shape, is generally much larger than native rocky bed material, and the size of trees entering a channel network generally increases downstream, which is opposite to inorganic sediment. In terms of engineering wood in rivers, a great deal of analysis is done to determine the longevity, stability, hydraulics and flow, habitat-forming processes, and physical complexity of the log jams, both before and after installation. Tim went over multiple types of wood installations, including stumps, snags, piles, and embedded root wad posts. He gave examples of successful restoration projects utilizing engineered log jams (ELJs) in the Hoko, South Fork Calawah, Upper Quinault, Little, Queets, Hoh, South Nooksack, and Cispus rivers. He described the hydraulic modeling that takes place before project development, and showed examples of modeling on the Hoh, Sauk, Big Quilcene, and Upper Quinault rivers, which measured the depth averaged velocity output from hydrodynamic modeling code FESWMS for proposed conditions during 100-year peak flow events. Tim noted that a 100-year flood event is not an event that happens every 100 years; it is an event that has a one percent chance of happening in any given year. He acknowledged that while models are always a simulation, they are tools that can give us information on the order of magnitude, or sensitivity, in a system. Typical methods for two-dimensional modeling ELJs involve raising the roughness value; altering the modeling surface to create a solid obstruction and raising the roughness value; and altering the modeling surface to create a porous obstruction and raising the roughness value. Mesh refinements are necessary for all methods. Raising the roughness value influences water surface elevation; is appropriate for highly porous, loose wood; is quick to apply to large areas; and is easy to do a sensitivity test on. Discussion followed on the FEMA 100-year flood maps, and how sea level models and the increasing frequency of extreme weather events make those projections insufficient. Also, the impacts of wildfires on erosion and runoff are not considered in the FEMA models. The “worst case scenario” is reoccurring more frequently. Tim ended his presentation with open discussion, which is summarized under Public Comments. 3 Project Updates There were no project updates. Next Meeting and Agenda The next meeting is tentatively scheduled for Saturday, May 18, 2024. Public Comments The group raised questions about changes to the river increasing flood risks, property concerns, possible changes to flood insurance, how to leverage funding opportunities, how to take future growth into concern, and how often the ELJs tend to fail. Tim explained that NSD’s designs are built to withstand 100-year flood events, with additional redundancies built in. So far, they have had very good success, but that has come out of comprehensive analysis, allowing areas to be dynamic, and providing an inventory of solutions that can be more protective than a single ELJ failure. Tim estimated that out of about 100 ELJs, about six have either failed or needed to be repaired. He noted that the designs have improved over time, so projects have a higher success rate now than they did 15 years ago. In terms of funding opportunities, restoration project funding does not tend to favor “people projects,” but funding can be applied to projects that benefit both wildlife and humans. Those are the ideal projects to benefit habitat and the community. Concerns were also raised about landowners taking their own actions without regulatory approval that could have negative impacts downstream, and how to best educate the community. Tami Pokorny and Tim shared some resources for additional information, including Jefferson County staff, NSD staff and research, and the National Oceanic and Atmospheric Administration’s Sea Level Rise Viewer, which can be found at https://coast.noaa.gov/slr/index.html#/layer/slr. Ideas and examples of projects on private property featuring bridge installations, riparian reforestation and revegetation, and wildlife fencing were discussed. Adjourn at 11:34 AM Summary by Rebekah Brooks