As flooding again impacts communities across Whatcom County, renewed debate has focused on whether dredging the Nooksack River could reduce future flood damage. Similar discussions followed major flood events in 2021 and other years, leading to task forces and studies. A change.org petition was created and Facebook groups have been filled with hundreds of comments loaded with misinformation.
Misinformation was also spread on a weekend radio show on KGMI in Bellingham by hosts Rick Todd and Lyle Sorenson. On the program, Radio Real Estate, the hosts incorrectly claimed the Nooksack used to be dredged and the gravel managed for flood control. This never happened according to Whatcom County records on the issue.
Despite on air claims and subsequent social media posts that the river used to be dredged during mining operations, past activity mainly involved gravel bar removal for commercial use.
The history is that flooding occurred even while gravel mining was active, indicating it provided no protection and dredging was not a comprehensive flood solution. Instead it increases flow and endangers everyone else downstream.
Despite past studies into the issues, the debate continues. The science is pretty clear as this isn’t theoretical science, but earth science and geology.
The Nooksack is fed by erosion from Mount Baker and Mount Shuksan. According to the U.S. Geological Survey, these headwaters consist largely of unconsolidated glacial and volcanic material that erodes easily during heavy rain and snowmelt.
USGS research shows the river continuously transports large volumes of sediment downstream. When sediment accumulates faster than it can move out, the riverbed rises and flood risk increases. Removing gravel from one reach does not stop sediment from arriving from upstream.
In fact, according to NOAA Fisheries, historic removal of large woody debris reduced the river’s ability to slow water and store sediment naturally. This channel simplification increased downstream flood energy and reduced habitat complexity. Modern restoration projects now place engineered log jams to partially restore those functions.
These log jams provide critical structure for Salmon and steelhead returns in the Nooksack basin and those numbers remain low as more and more of that structure is moved by human activity. NOAA reports these declines are driven by multiple factors including altered streamflows, warmer water temperatures, habitat loss, and sediment instability. NOAA does not identify dredging as a recovery strategy for steelhead, noting unmanaged sediment removal can damage spawning habitat.
According to NOAA and USGS monitoring, glaciers on Mount Baker and Mount Shuksan have retreated significantly. Glacier loss increases sediment delivery to rivers and alters runoff timing. While dredging is still technically possible, agencies note that increased sediment supply reduces how long gravel removal remains effective.
The former Sumas Lake once provided natural flood storage. After the lake was drained for agriculture, floodwaters became confined by dikes and pumps. During extreme floods, water can still flow into the basin and overwhelm pumping systems.
According to the Washington Department of Ecology, long term flood risk reduction relies on combined strategies. These include floodplain reconnection, levee setbacks, engineered wood placement, targeted gravel management, and land use planning in high risk areas.
According to NOAA, USGS, and state flood managers, the Nooksack River is responding to geology, climate trends, and decades of river modification. Dredging may provide limited, short term benefits in specific locations, but it is not a standalone solution for a sediment rich, glacier fed river system.
Despite the facts, the reality of the issue is that doing nothing at all is not a sustainable plan either. Acknowledging that water is going to go where water is going to go, one must acknowledge the watershed extends over the border into Canada near Sumas and Everson. That’s the geology of the situation.
What local, state, and federal partners can do to mitigate where the increase in water volume is going to go is the only question. History shows on the Canadian side of the border Sumas Lake was filled to create farmland. When major high water events occur on the Nooksack, the water returns over city streets because the water system below them is still there.
That’s where the historic backfill went during high water events, so that’s where the water goes during modern flood events whether in 2021 or 2025 or the early 90s flood. Canadians want Americans to come up with the solution, which would likely entail creating a new fill area south of Everson to draw water south. There are natural basins and lakes throughout that area, but you’re talking about displacing far more people and having far greater environmental impact.
This is probably why the taskforce members threw their hands up in the air and let locals fend for themselves. The status quo is have the governor and legislators show up and pay lip service, offering $3.5 million for flood victims this year and then go back to Olympia and argue over plastic bags.
Many have pointed to the success of the Mount Vernon Downtown Flood Protection Project, completed in phases by 2019. That system involves concrete floodwalls and earthen levees which cost over $31 million in total, providing FEMA-certified protection and reducing insurance rates by removing the downtown area from flood zones.
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