The mighty Columbia River marks the northern boundary of Oregon’s North Coast and is by far the most significant watershed in the Pacific Northwest. It is also one of the most heavily plumbed and utilized waterways in North America. Partly because of this, industries have concentrated around the river and within the wider basin. Unfortunately, much of that industry along with millions of individual homeowners, agricultural producers, mines and timber operations have contributed to a mighty toxic load in the river.
January 19th, the Environmental Protection Agency released a relatively thin report on toxins in the river and major tributaries. Quoting directly from the report, here are some of the grim facts about our river:
While many contaminants have the potential to be of concern, this report focuses primarily on four contaminants: mercury (including methylmercury); DDT and its breakdown products; PCBs; and PBDEs. These contaminants are of primary concern because (1) they are widely distributed throughout the Basin; (2) they may have adverse effects on wildlife, fish, and people; (3) they are found at levels of concern in many locations throughout the Basin; and (4) there is an opportunity to build on current efforts to reduce these contaminants within the Basin.
In addition to these four contaminants, many other contaminants of concern were also identified in the Basin. These included metals such as arsenic and lead; radionuclides; several types of pesticides, including current-use pesticides; industrial chemicals; combustion byproducts such as dioxin; and “emerging contaminants” such as pharmaceuticals and personal care products.
The report highlights how mercury–an unfortunately common contaminant in fish tissue–has been a persistent issue within the Columbia.
Mercury enters the Columbia River and its tributaries via several pathways, including atmospheric deposition, runoff, wastewater discharges, industrial discharges, and mines. Based on available data, atmospheric deposition appears to be the major pathway for mercury loading to the Columbia River Basin. Mercury air deposition includes both emissions from industrial facilities within and near the Basin and fallout from the pool of global mercury that has been can contribute the majority of mercury deposited on the local landscape.
EPA estimates that the total mercury air deposition in the Columbia River Basin of is 11,500 pounds of mercury per year. Approximately 84 percent of that load comes from global sources. At a watershed scale, however, local and regional sources constitutes an estimated 62 percent of the air-deposited load in that area.
What is to be done?
If you see health advisories that recommend limiting fish and shellfish consumption in the Lower Columbia, heed them. They are becoming rare but ultimately declared to protect human health.
Take care to reduce your own use of mercury-containing products. Dispose of these products on community-sponsored hazardous waste collection days only.
Reduce your energy consumption–especially in communities that depend upon coal-fired plants for some portion of their electricity. Coal plants are the primary emitters of atmospheric methylmercury.
Reduce soil erosion into the mainstem and tributaries of the Columbia. Soils in agricultural and industrial areas often contain some of the most powerful and persistent toxins that contribute to the overall load in the river (PCBs, DDT, Dioxins, PBDEs).
Reduce your own toxic contribution to the atmosphere, soils and waters by practicing organic gardening in your home landscape or vegetable patch. Where organic approaches aren’t appropriate, try reducing your pesticide use by applying the chemicals during the times when they will be most effective and less likely to drift from their targets. Read and follow instructions on the label.
Don’t dump your extra or expired pharmaceutical products into the toilet or sink. Dispose of these in their original sealed containers at your local landfill.