DESCRIPTION
Whidbey Island Conservation District (WICD) will complete a study of the feasibility of restoring tidal connectivity and fish passage into an approximately 18 acre brackish lagoon and freshwater marsh system in Greenbank, Washington. The project site, most of which is owned by the Greenbank Beach and Boat Club, Inc. (GBBC), is the relict of a larger tidal marsh that occupied the area prior to settlement in the 19th Century. The assessment will evaluate geomorphic, hydrologic, land use, ecological and other relevant factors to determine the effectiveness and likelihood of community acceptance of various engineered options for meeting two primary objectives: 1) restoring nearshore rearing habitat conditions for ESA-listed Puget Sound Chinook salmon and 2) improving the reliability and capacity of the stormwater drainage system at the site. The assessment will include developing and evaluating conceptual design alternatives for achieving the objectives, working with the landowner and other community stakeholders to select a preferred alternative, and then preparing a preliminary engineering design of the preferred alternative, per the guidelines in RCO Manual 18.
WICD and the property owner, Greenbank Beach and Boat Club (GBBC), successfully accomplished several objectives essential to meeting the goal of this multi-phased project. Objectives in this project phase focused on three broad activities: characterizing site conditions, evaluating legal responsibilities, and consulting with stakeholders. Specific findings from these activities were then used to evaluate four design alternatives, with stakeholder input, and subsequently develop a preferred conceptual design. See "Conceptual Design Report, SRFB Project No. 15-1072, Greenbank Marsh Restoration Issues Assessment" in Attachments for full project details.
The project site characterization process involved hiring professional service consultants to provide the bulk of baseline studies and reports. Some studies were carried out by WICD's in-house professional engineer and other staff. This work included a cultural resource assessment, reconnaissance-level wetland assessment, topographic and tidal elevation surveys, hydrologic modeling, hydrogeologic and septic system investigations, coastal sediment transport and wave power studies, and a reference site evaluation. Upon completion of these studies, WICD's engineer reviewed the data, reports, and consultant recommendations then utilized this information to evaluate the following four conceptual design alternatives: 1) replace outfall pipe, 2) partially restore tidal flow, 3) fully restore tidal flow with a self-regulating tidegate in the marsh, 4) fully restore tidal flow without a self-regulating tidegate in the marsh.
The legal evaluation entailed hiring a local law firm to evaluate obligations and liabilities of various entities and property owners with existing infrastructure draining to the GBBC-owned tidegate. The law firm conducted extensive research and produced a memorandum clarifying that property owners of the dike, including GBBC, and Island County have potential liability if property damage occurs from surface water within this area depending on the circumstance. The memorandum also describes GBBC's responsibility to maintain proper function of the tidegate and provides options for minimizing liability including creation of a diking/drainage district, boundary line adjustment and divestment of tidegate property, or habitat restoration to remove any obstructions of the natural flow of water. WICD staff and GBBC board members met with the law firm several times to review and discuss these obligations and strategies for moving forward with the project.
Stakeholder consultation occurred throughout this project phase and included government agencies, neighboring property owners, and other local interests. Beginning in early 2016, soon after the project was funded, WICD and the GBBC board held two outreach events, one for GBBC members and one for the public, to introduce the project, answer questions, and encourage feedback. Approximately 90 people attended these initial events and feedback was recorded. The next year WICD and GBBC re-visited the original outreach events to share study results, request feedback, and discuss next steps. Again, about 90 people combined attended these two events. The first was a return to GBBC's annual membership meeting in February 2017. WICD's engineer gave an interactive presentation about the completed project studies, legal obligations, and his evaluation of the four conceptual design alternatives. The GBBC board then surveyed members to assess support for a preferred design alternative and collect general feedback regarding the project. This survey identified a majority of GBBC members supporting alternative #3, to fully restore tidal flow with a self-regulating tidegate in the freshwater marsh (open-channel). This support permitted WICD's engineer to focus on refining the "open-channel" conceptual design based on stakeholder input and study data. WICD staff simultaneously developed a project webpage on the WICD website to serve as a portal for the public to access project information and submit feedback. WICD staff and GBBC board members also met with Island County's Public Works director and a Port of Coupeville Commissioner in May 2017 to explain the preferred design alternative and request input. Both were generally supportive of the project moving forward as proposed. In June 2017, WICD and GBBC held a second public event to share project results, discuss the design evaluation process, introduce the preferred "open-channel" conceptual design, and, again, ask for community feedback. Attendees provided valuable input and were generally supportive of the proposed restoration project. Out of this event, interested stakeholders (including GBBC, WICD, Port of Coupeville, and Island County) formed a committee (Greenbank Marsh Working Group) to cooperatively consider local drainage issues and connections with this proposed restoration project. This committee meets about once a month and will continue to do so as long as there is interest. Lastly, an artist's rendering of the conceptual design was produced and printed in poster size for outreach purposes.