2022-10-24-minutes-public-works-study-session

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wood structures to improve bull trout holding, spawning, and rearing habitat. Kittitas Conservation Trust is seeking a total of $25M from additional funding sources to address the implementation costs for the restoration of Gold Creek. Implementation will occur in separate phases as funding is acquired within the next three to five years. 6. Project Narrative: Describe the projects goals, objectives, methods, benefits, etc. Is it part of a multi- year project? !f so, explain what year(s) the funding you seek will cover, and how other years of the project will be funded. Problem Statement Gold Creek, located near Snoqualmie Pass in Washington State (Figures 1 through 4), is listed as critical habitat for ESA threatened bull trout, Solvelinus confluentus. As a snow -fed creek, it historically dewaters annually in the late summer. However, nearly a century of anthropogenic landscape alterations to the watershed have drastically increased the frequency, extent, and duration of dewatering. In 2013, Natural Systems Designs (NSD) collected monitoring data from June to October, identifying the frequency, extent, and duration of dewatering (Figure 5). Under the current conditions, over one mile of creek dewaters annually, persisting from mid-July to late September, creating a fish passage barrier for migrating adults and increasing juvenile mortality due to stranding. This is problematic, as bull trout in Gold Creek are on the verge of extirpation. Gold Creek Valley has been the site of numerous gravel pits utilized for the construction and expansion of Interstate -90 in Washington State. To expand 1-90 to its current state, in the 1970s through the 1980s Washington Department of Transportation (WSDOT) needed large quantities of gravel. More than 750,000 cubic yards of gravel were extracted from Gold Creek Pond, forming a 27 -acre pond, which covers about 78% of the valley bottom and the entire eastern floodplain of Gold Creek. Gold Creek Pond has yet to be restored to its original condition. Due to the size and location of Gold Creek Pond, the pond negatively impacts the groundwater dynamics across Gold Creek Valley. Data from the 2013 and 2014 hydrology monitoring periods documented that the pond acts as a siphon pulling water away from Gold Creek, magnifying the seasonal dewatering effects on the creek. Heli's Pond, a smaller 2 -acre gravel pit just north of Gold Creek Pond, was excavated in 1996 as a source of gravel for resurfacing roads, also causes dewater effects to Gold Creek. Gold Creek has been negatively impacted by decades of clear-cut logging and mining, which caused an over -widened channel with little complexity or cover. The over -widened channel causes the flow to go sub -surface, further exacerbating the effects of dewatering. In addition, WSDOT created a levee to separate the creek from the gravel pit to keep water from entering the work site. The levee continues to disconnect the creek from 90% of its floodplain. Furthermore, water in Gold Creek Pond creates a heat -sink during the summer, which can create lethal temperatures for bull trout. Regional climate models show a significant decrease in base stream flows associated with lower spring snowpacks resulting from more winter precipitation falling as rain. The models show the air and water temperatures within the watershed becoming warmer and summers becoming dryer, all of which further exacerbate the dewatering in Gold Creek. The restoration proposed below will help mitigate climate change by capturing seasonal rain events to keep the creek watered longer. 14