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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Ocean/Envir 260 Lecture #9: Unique Issues: Elwha River, Duwamish River, and San Juan Islands 1
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Elwha River Key facts: –Largely protected watershed –Legendary salmon runs blocked since 1910 –Sediment also blocked –Dams coming down, 2011 - 2014 2
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Elwha River Dam removal –Long delayed –$350M total cost –Sediment major concern Aggrade downstream? –Cause flooding? –Overwhelm habitats? –Staged removal Rely on natural sediment flushing 3 Elwha Dam, River Mile 5
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Elwha River Dam Removal –National-scale experiment Sediment unavoidable issue –How quickly salmon return? How much genetic legacy lost? Wider ecosystem benefits? Cost-effectiveness of investment? 4 Glines Canyon Dam, River Mile 13 (inside Olympic National Park)
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Duwamish River Key facts: –Massively altered watershed Cedar River, Lake Washington rerouted White River diverted 5 Current major watershed boundaries, King County
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Duwamish River Key facts: –Lower river “tamed” Dredged, straightened Port, industrial growth –Flood control dam “More land for industry” Conversion of Green R valley from farms 6 Historic mouth of Duwamish River: tidal marshes (red) and mud flats (white); rail lines over mud flats, early 20 th Century (below)
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Duwamish River Key facts: –Massive pollution Harbor Island “superfund” site Industrial heart of region –Pollution continues –So do salmon, wildlife 7 North Boeing Field, Georgetown Steam Plant site: after 4+ years, still uncertain where PCBs originate
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Duwamish River Extremely expensive to clean up sediments –$300M+? Habitat restoration to be required similarly costly –Compensate for past pollution 8 Harbor Island, Seattle, created by spoils when lower Duwamish was dredged in early 1900s
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Duwamish River Issues: –Costly actions led by different orgs, mandates –How much clean-up/ restoration is required? –Who is responsible? –Where should restoration funds be spent? 9 Kellogg Island, only wooded island on lower Duwamish River
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington San Juan Islands Key facts: –Important to whole Salish Sea Salmon, orcas, marine birds, rockfish… –Small, fast growing human population –Shoreline relatively intact Protection highest priority 10 Geologically, the San Juans extend to Fidalgo Island (bottom right); ecologically, they blend with the Gulf Islands off of Vancouver Island (top left)
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington San Juan Islands Challenges: –Expensive shoreline property Can’t purchase large amounts Landowners quick to sue –Rural, low budget county –Diverse shoreline ecologies 11 Water view home, San Juan Island
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington San Juan Initiative Collaborative process –Regulations, education, incentives Treat rocky shores, beaches differently –Discourage shoreline armoring –Vary house setbacks by erosion rate –Flexibility and nuance vs. consistency, simplicity… 12
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Discussion question Should funds from Duwamish restoration requirements be spent in other places, where they would provide greater ecological benefits? –Yes –No –Defend your position 13
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Ocean/ENVIR 260 Autumn 2010Lecture 9© 2010 University of Washington Recap: Elwha, Duwamish, San Juans Issues across Sound vary based on distinct ecologies, historical alteration Protection is priceless, not always feasible Restoration is expensive –Higher price, generally lower returns in most altered places Political, moral dilemma to redirect funds 14
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