Sumner looks to mitigate flooding from the White River with a $99.5 million project creating wetlands.
Snowmelt from Mount Rainier and heavy rainfall occasionally flood the White River, leaving Pierce County’s largest manufacturing center underwater.
Doug Beagle, Sumner’s deputy director of Public Works, said the river’s high waters could lead to flooding in residential areas downstream.
“River bed is filling up, and we need to create space for the river to go,” said Beagle, who is coordinating the mitigation project. “We want to give this back to nature, protect these habitats and the citizens as well.”
The river flows against its natural path after being rerouted by farmers for irrigation. The man-made route has caused issues for decades, like sediment and debris from Mount Rainier building up. Two years ago, FEMA adopted new flood maps to include most of the industrial sites in North Sumner.
The movement to address flooding began in 2015 when Sumner went to the state Legislature for funding. There had been flooding in the industrial district, most notably at a warehouse deemed a toxic site by the Department of Ecology in 2009, and the city wanted help to find solutions.
The state granted Sumner $824,000, jump-starting four years of designing and collaboration between the city, state, Pierce County, Muckleshoot Indian Tribe, Puyallup Tribe of Indians and BNSF Railway.
The plan grew to include four projects along The White River:
• Stewart Road Bridge ($30 million): The two-lane bridge is currently a “choke point” for the river. Plans would expand it by 100 feet to the east.
• Left-bank setback ($25.7 million): Once the water passes under the bridge, planners want to create an embankment to hold water at higher levels.
• Pacific Point bar ($20.7 million): At the curve of the river, a levee would be added to protect the 25 industrial sites on the south bank, including an Amazon warehouse.
• 24th Street setback levee ($38.3 million): 170 acres would be converted into wetlands by removing 5 to 9 feet of soil, planting trees and allowing the river to fill up. This portion of the project would improve habitat for endangered species like chinook and sockeye salmon.
The projects would affect the nearby railroad and trail.
BNSF Railway is in negotiations with Sumner to purchase a 9,000-foot stretch along the project to add new tracks. As passenger trains grow in demand, Beagle said cargo trains need space to “pull over” and allow commuter trains to pass. The soil extracted for the wetlands will be used to construct the staging yard.
The Interurban Trail would be moved to cross the White River at the Stewart Road Bridge and follow along the railroad tracks, Beagle said.
Sumner still is collecting money to “undevelop” the 170 acres for the wetlands project but hopes to start construction in the next year and a half. Sumner has pledged more than $15 million to address the first step, moving utility and stormwater lines and covering legal fees, Beagle said.