Union Bay Natural Area a Dynamic Mosaic of Visions
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Union Bay Natural Area A dynamic mosaic of visions Rodney Pond, Executive Director Sound Salmon Solutions Our 40ish minute trip A human history of UBNA A natural history of UBNA Modifying the mosaic: Strategies, references & visions Dxʷdəwʔabš (Duwamish) Tribe “SWAH-tsoo-gweel ('portage'). Duwamish. Around the top margins of Union Bay. Five longhouses were located on the N edge of the bay, which--pre-1916--lay nearly a mile further N. One longhouse was near the present UW steam plant, and one near the former Battelle Institute campus. This was the principal village of an influential group known as hloo-weelh-AHBSH who took their name from the s’hloo-WEELH (literally, "a tiny hole drilled to measure the thickness of a canoe"), the narrow passage through the resource-rich Union Bay marsh.“ “Coast Salish Villages of Puget Sound” http://coastsalishmap.org/start_page.htm Yesler’s Sawmill “The community, variously known as the Town of Yesler, Yesler Mill, Yesler Junction, or simply Yesler, was laid out in 1888 as something like a company town to support Henry Yesler's second mill, located on the north shore of Union Bay, an indentation on the western shore of Lake Washington between the present-day University of Washington campus to the west and the Laurelhurst peninsula to the east.” Eleanor Boba, “Yesler Mill on Union Bay” https://www.historylink.org/File/11244 ca. 1890 Lake Washington Ship Canal “On Friday, August 25, 1916, with the armoring of the Montlake Cut's walls complete, the Corps of Engineers began the long-awaited "union of the waters" of Lake Union and Lake Washington... At 2 p.m., workmen with shovels opened up a small cut in the third and final cofferdam at the west end of the Montlake Cut. The stream of water pouring into the cut from Lake Union quickly turned into a raging torrent, causing crowds on the cofferdam to flee the water, dirt, and huge timbers of the rapidly disintegrating dam…Three days later, after crews had cleaned out the debris in the cut, the corps opened gates at the east end and began to lower Lake Washington... Lake Washington dropped two feet in the first week and four feet in the first month. After that it dropped up to two inches a day. As the water level dropped, it fell below the lake's drainage outlet to the Black River, and the river eventually dried up. The ship canal became the lake's new outlet. By late October, Lake Washington had lowered a full nine feet and was equal in elevation to Lake Union and Salmon Bay…” David B. Williams “Lake Washington Ship Canal (Seattle), https://www.historylink.org/File/1444 Montlake Landfill (1926-1968) “With the lowering of Lake Washington, marshland that had been confined to the northern end of Union Bay just north and east of the Montlake Cut was greatly enlarged, reaching to as far south as today's Husky Stadium. The newly exposed land, which held the largest and deepest peat repository in Washington state, was thought to be unbuildable and to have little use and less value…In 1926 it was decided that the marsh could best serve the city as a receptacle for the growing mass of garbage and rubbish that rapid population increases had brought…This started the process of environmental degradation of Union Bay that would, more than a half century later, provide a living laboratory in which to test the ability of humans to atone for past environmental sins. ” John Caldbick, “Union Bay Natural Area (Seattle)” https://www.historylink.org/File/10182 1937 You are here Landfill Landfill ca. 1946 You are here 1952 landfill Drainage channels You are somewhere over here UBNA natural history - a hydrogeomorphological tale Glacier marsh marsh/lake ~11,000 years advancing X 4ish Glacier lake more marsh, less lake retreating clay soil cap over fill ? Compressible layers of history 3’-6’ clay soil cap lake ~15’-40’ landfill waste 40’ 40’ berm - 15’ Up to 100’ peat Emergent ecosystem mosaic reclamation actions – grading & seeding winter precipitation/summer drought very poorly drained clay soils undulating topography transitions grassland swamp scrub-shrub marsh lakeshore Modifying the mosaic – restoration pathways existing vegetation transitions grassland swamp marsh scrub-shrub lake shore modify & transition modify & transition enhance & expand enhance & expand enhance & expand prairie forest enhance & expand swamp marsh introduced species scrub-shrub lake shore indigenous species dominant dominant Modifying the mosaic – reference ecosystems in the real world target/reference ecosystem prairie forest scrub-shrub swamp marsh lake shore soil moisture long seasonal drought short seasonal saturation perennial hydrology well drainage moderate seasonal inundation perennial UBNA primary ecosystem stressors summer drought poorly drained clay soils introduced grasses & forbs modification & resource subsidy to achieve reference relevance of reference ecosystem Modifying the mosaic – restoration strategies indigenous dominated habitat references on-site potential vegetation in invasive control & similar habitats supplemental planting nearby intact/restored similar increases diversity habitats & complexity requires low levels of upfront and on-going modification & subsidy swamp lake shore scrub-shrub marsh Marsh - Shoveller’s Pond, UBNA Swamp – Yesler Swamp, UBNA Swamp – Yesler Swamp, UBNA Swamp – Yesler Swamp, UBNA Swamp – Yesler Swamp, UBNA Modifying the mosaic – restoration strategies references grassland forest/shrub-scrub nearby intact/restored similar soil manipulation habitats alters soil moisture less on-going modification & subsidy required prairie distant but within ecoregion extensive on-going modification & subsidy required forest prairie scrub-shrub 2013(?) Grassland prairie restoration, 2019 Scrub-shrub border restoration, 2001 Scrub-shrub border restoration, 2001 Scrub-shrub border restoration, 2019 Mixed deciduous-conifer forest restoration, 2004 Mixed deciduous-conifer forest restoration, 2011 Modifying the mosaic – restoration strategies gravel parking lot references marsh(?)/lake shore/shrub-scrub topographic modification nearby intact/restored similar habitats alters hydrology extensive upfront but less on- going modification & subsidy required prairie distant but within ecoregion marsh extensive upfront and on-going prairie modification & subsidy maintain edge elevation edge maintain required scrub-shrub lake shore E-5 parking lot prairie restoration, 1998 E-5 parking lot prairie restoration, 1998 Mima Mounds, South Puget Sound 1998 E-5 parking lot prairie restoration, 2019 1998 E-5 parking lot prairie restoration, 2019 Future E-5 parking lot marsh restoration site, 2011 Recent E-5 parking lot marsh restoration, 2019 Who’s UBNA? – valuing ecosystems in the real world target/reference ecosystem prairie forest scrub-shrub swamp marsh lake shore not wetland WSDOT – regulations compliance displaces grassland birds Seattle Audubon - birdwatchers SEFS/UWBG Students – education & research opportunities Laurelhurst safety – reduced visibility Laurelhurst neighborhood restoration disturbs hooded ladies’ tresses Washington Native Plant Society blocks view landscape photographers of Mt. Rainier swamp/marsh introduced grassland valued less controversial Red Eagle Soaring giving a blessing, 2004 Thank you! Questions?.