Future development of the Simpson Mill area at Lowell is a matter of regional concern for lowland residents whose safety and property is threatened by floodwater runoff. It involves nearby residents from Ebey Island and Marshland and more distant Snohomish Basin residents up to 60 miles away in King County. The Simpson area is local, but its impacts on floodwater are regional.
Since the early Holocene era the combined waters of the rivers Tolt, Snoqualmie and Skykomish have joined to form the Snohomish River near Monroe. The Snohomish then flows northwestward to Possession Sound. Most of the Snohomish channel flows peacefully through a flood plain and tidal estuary most of the time.
In flood season the water flow can increase to a volume and destructive force consistently underestimated by visitors and planners alike. During the great flood of 1990, its discharge measured at Monroe reached 186,000 cubic feet per second, some 12 times the river’s normal rate of flow.
The Snohomish River channel collides squarely with glacial outwash uplands at Lowell. In prehistory it formed a great loop there, which bends back upon itself into the flood plain. The westernmost segment of flood plain thus formed is the Simpson site. The channel bend itself exceeds 110 degrees, forming a floodwater bottleneck of its own making.
Since the early 1890s, this bottleneck has been worsened by uninformed land-filling. The channel’s great loop that formed its widest point in prehistory (an estimated 550 feet) has been reduced to 283 feet by landfill. Today the river is vigorously trying to reclaim its old channel by erosion. It is believed that in the meantime the constraints on floodwater flow there contributed materially to the enormous damages produced upstream in Ebey Island, Marshland and French Creek by the floods of 1975, 1986, 1990 and 1995. The same constraints foreshadow alike the new developments planned for the Simpson area and for regional farmers and residents far upstream.
Powerful new floods will come. It is only a matter of time.
Everett planners to date have underappreciated the absolute dominance of the Snohomish River in Simpson site affairs. It is a non-negotiable determinate factor in the Snohomish Basin destiny – an area of 1,900 square miles and home to 350,000 souls. The Simpson site’s 100 acres is a flyspeck on the basin’s 1.2 million acres. In planning the site’s future there is much more to accommodate than the Lowell neighborhood. All of Everett, much of Snohomish County and a big piece of King County have a stake in plans for the Simpson bottleneck.
Small rises in the river are not the problem. Severe rising, with discharges exceeding 166,000 cubic feet per second at the Corps of Engineer’s Monroe gauge and 33 feet depth at the Snohomish gauge, are the issue of concern. The real problem is the floodwater backup into upstream areas owing to water-flow delay by the Simpson bottleneck at Lowell. These county areas include Drainage District No. 1, Marshland and the French Creek region, some 16,000 acres total. Such rising occurred in 1990 and 1995 with great devastation upstream. But from the beginning, Everett representatives have never recognized the interregional nature of the Snohomish River. Their historic channel point at Lowell has been so heavily land-filled that it was not overtopped even by the Century Flood of 1990.
However, Everett’s moment with the Snohomish is at hand. Not only is the riverfront at Lowell already eroding severely, but projections based on historic flood data (1940-1990) indicate levels of 35 feet by 2012 and 38 feet by 2049. The latter would be decisive against all human enterprise save agriculture and planned biosphere-integrated facilities.
In a recent paper, I presented the case for an integrated planning effort for the Simpson site. It would involve Everett and county regional planners well-versed in Snohomish River floods and their management. A primary goal would be the restoration of the river’s prehistoric channel at Lowell.
Also proposed are new development options not previously considered by Everett planners. These include the creation of a “Biosphere Park” in the Simpson area. Its primary elements consist of a tidal basin, a reflection pool, a wetland botanic garden and a wetland arboretum. The tidal basin motiff is based on the U.S. national tidal basin in Washington D.C., which utilizes tide waters of the Potomac River. A Native American museum and archaeological site would celebrate the area’s usage by man since the early Holocene and Proglacial periods. The Biosphere Park concept includes midway docking for stern-wheeler tours of the Snohomish River estuary. Short excursions from Lowell to Snohomish would complement extended tours to Possession Sound, Marysville, Steamboat Slough, Union Slough, Ebey Slough, Otter Island and the lower Snohomish River estuary.
Immediate beneficiaries would include the visiting public, basin residents from Marysville to Duvall and wetland wildlife forms that cannot speak for themselves. Correctly presented, the Biosphere Park design would draw the national attention of conservation researchers and educators, and environmental/conservation planners. The city of Everett would not need to spend more than seed money. However, Everett would need to contribute more in the way of homework, vision and river appreciation.
Planned with thoughtful vision, the developed Simpson area can be a non-threatening neighbor of Snohomish County, and a national feather in the hat of Everett unrivaled elsewhere in the United States.
Plant physiologist Alex G. Alexander lives on Ebey Island.
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