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Duwamish River Duwamish Study Area Water Quality Assessment and Monitoring Study Science and Technical Review Team January 22, 2014 Kate Macneale Water Quality Assessment Study Areas • Lake Union / Ship Canal / Montlake Cut • Elliott Bay • Duwamish River History of altered flow • Pre 1900: Duwamish River fed by Black/Cedar Rivers and Green/White Rivers • 1906: White River diverted to Puyallup River • 1911: Cedar River diverted from Black River to Lake Washington • 1913: Tacoma begins diverting water from Green River • 1916: Ship canal opened, lake level dropped, Black River no longer outlet of Lake Washington • 1962: Howard Hanson Dam (RM 65) completed for flood control • Current flow ~30% of historic flow Cedar River Green River Black River History of channel alterations Pre 1880s: • flooding frequent • complex freshwater marsh habitat • extensive estuary and tide flats 1900 – 1940s: • estuary tidelands filled, drained and dredged for industrial and port activities 1885-1980: • Green/Duwamish channelized and diked for navigation and flood control Result: Duwamish now shorter, steeper, simpler East West Waterway Waterway Duwamish River defined Lower Duwamish Waterway Duwamish River RM 11.0 Green River History of altered water quality • Water quality likely altered by human activities since early 1900s pesticides phthalates dioxins &furans dioxins nutrients metals PCBs TSS temperature pharmaceuticals PAHs bacteria dissolved oxygen activities pH Logging x x x x Dredging/channelization/regrading x x x x Discharge of sewage & stormwater x x x x x x x x ? x x x Agriculture/livestock production x x x x x x x x Industrial & shipping activities x x x x x x x Urbanization x x x x x x x x x x x x x History of altered water quality • Water quality likely altered by human activities since early 1900s pesticides phthalates dioxins &furans dioxins TSS temperature pH nutrients metals PCBs pharmaceuticals activities bacteria dissolved oxygen PAHs Logging x x x x Dredging/channelization/regrading x x x x Discharge of sewage & stormwater x x x x x x x x ? x x x Agriculture/livestock production x x x x x x x x Industrial & shipping activities x x x x x x x Urbanization x x x x x x x x x x x x x History of altered water quality • Water quality likely altered by human activities since early 1900s pesticides phthalates dioxins &furans dioxins TSS temperature pH nutrients metals PCBs pharmaceuticals activities bacteria dissolved oxygen PAHs Logging x x x x Dredging/channelization/regrading x x x x Discharge of sewage & stormwater x x x x x x x x ? x x x Agriculture/livestock production x x x x x x x x Industrial & shipping activities x x x x x x x Urbanization x x x x x x x x x x x x x • High concentrations of persistent contaminants led to designation of Lower Duwamish Waterway as a superfund site in 2001 Lower Duwamish Waterway superfund site East • Legacy contaminants in sediments West Waterway • PCBs Waterway • PAHs • Dioxins/furans • Arsenic, mercury and other metals Lower Duwamish • Clean-up initiated Waterway • Cleanup at Norfolk CSO in 1999 • Additional cleanup at Norfolk in 2003 Duwamish • Cleanup at Duwamish/Diagonal CSO 2005 River RM 11.0 • Cleanup at Slip 4 2012 • Cleanup at Boeing Plant 2 2013 Green • 1999 report indicate CSOs not a significant River source of PCBs, TBT, arsenic Current uses Industrial / Commercial / Heavy Urban Medium Urban Light Urban Natural Resources Open Spaces Current uses Industrial / Commercial / Heavy Urban Medium Urban Light Urban Natural Resources Open Spaces Agriculture/pasture Current activities that may affect water quality • Industrial activity including shipping • Spills and illegal dumping • Stormwater discharges (increased impervious areas) • Untreated CSO discharges • Urban and suburban living (home/garden care, pet waste, etc.) • Agriculture and livestock production • Wildlife use of watershed • Upcoming / ongoing projects – Continued cleanup, capping of Lower Duwamish Waterway – Dredging – King county and Seattle CSO upgrades Water quality criteria designations Criteria Aquatic life uses Recreation uses 1 2 marine freshwater spawning/rearing Char habitat summer core spawning/rearing only rearing/migration contact extraordinary contact primary contact secondary 1 x x x 2 x x x 3 3 x x x 4 x x x 5 x x x 4 5 Water quality listings - Lower Duwamish Waterway (area influenced by CSOs) Sediments Water PCBs Bacteria PAHs DO Metals Ammonia Phthalates Phthalates Other SVOCs Tissue PCBs HPAHs Dieldrin Other SVOCs Requires TMDL Water quality listings - Duwamish River (area upstream of CSOs) Tissue Water PCBs Temperature PAHs pH Arsenic DO Phthalate phthalate Other SVOCs Requires TMDL Water quality listings - Green River and tributaries Water Bacteria DO DO, bacteria Temperature Copper pH Ammonia bacteria Phthalate Mercury DO Endrin PCB DO, Toxaphene bacteria DO DO bacteria bacteria DO, bacteria Combined stormwater and sewer systems Partially separated systems Fully separated systems CSOs and stormwater discharge locations King County controlled CSO King County uncontrolled CSO Seattle controlled CSO Seattle uncontrolled CSO Stormwater outfall CSO improvements • Harbor pipeline (2000/2001) • Hanford #1 – partial separation of basins, reduced discharges (1992) • 378 MG to 7 MG • Brandon/Michigan – upsized regulator pipe • 254 MG to 121 MG • Henderson/Norfolk – increased storage and added primary treatment facility, overflow of treated water to Norfolk CSO (2005) • 39 MG to 0 MG Allentown diversion – reduced flows at King County controlled CSO Norfolk (1995) King County uncontrolled CSO Water quality sampling stations • Parameters same as those collected for marine sites • Stations sampled monthly • Years sampled at each site, from downstream to upstream: 1996-present 2004-present 1986-2004 Water quality monitoring station 2007-2010 King County controlled CSO 1986-present King County uncontrolled CSO 2009-present Seattle controlled CSO Seattle uncontrolled CSO Stormwater outfall Green River watershed water quality sampling stations Station downstream of CSOs Green River station upstream of CSOs t Tributary station upstream of CSOs E Ecology monitoring station E (conventionals, bacteria, metals) Years sampled at each site, ordered downstream to upstream: 1986-2008 1986-present t 1990-present (E) 1986-2008 1977-present (t) t E 1986-present (t) 1986-2008 1972-present (t) t 1986-present 1975-present (E) Sediments and Tissues • Extensive sediment sampling conducted in waterways, detailed in superfund site reports • Tissue samples also available from limited sites, still compiling data Duwamish River Conclusions • Duwamish River altered for 100+ years • Ongoing and historical sources of contamination • Uncontrolled & controlled CSOs continue to discharge into Lower Duwamish Waterway, but discharges have declined since 1970s • Some parameters of concern (e.g., bacteria) exceed water quality standards at sites within and upstream of CSOs • Long-term ambient monitoring data exist at several stations within and upstream of CSOs • No recent data targeting CSO discharges, either spatially or temporally .
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