Monitoring: The Key to Understanding and Protecting Flathead Lake, Robin Steinkraus


“Water is life’s mater and matrix, mother and medium. There is no life without water.”
- Albert Szent-Gyorgyi, 1893 - 1986

Figure 4.30: Water lilies. Source: Lori Curtis

Keeping Our Water Clean
The backbone of the Flathead Watershed is quality water. Our many rivers and streams recharge groundwater and create floodplain areas, riparian corridors, and wetlands that sustain water quality throughout the watershed. These natural systems filter nutrients, trap sediments, reduce flooding, and stabilize soils. Together, these functions sustain our rapidly growing population, our wildlife and fisheries, and our timber, agriculture, and tourism industries.

Federal, state, tribal, and local agencies develop rules and implement regulations to protect the health of our water and our way of life. These rules and regulations include a permitting processes and citations for violators. The economic and environmental costs of poor water quality, particularly in an area renowned for its natural resources, can be substantial. Poor water quality can:

The context for assuring water quality is the federal Clean Water Act, which serves as a model for Montana’s Water Quality Act. Water quality standards have been developed by the Montana Department of Environmental Quality (DEQ) to ensure healthy and productive water systems for the natural environment and the people who live, work, and play in the watershed. State and local scientists analyze sediments, nutrients, metals, aquatic insects, and algae in order to determine the health of our waterways. For waters not meeting Montana standards, one framework for meeting water quality standards is the DEQ Total Maximum Daily Load (TMDL) process. The TMDL is the maximum amount of a pollutant a given water body can handle before possibly incurring significant problems.

“I don’t think you will find anybody on the surface of the earth today that doesn’t have at least 500 measurable chemicals in their bodies that were never in anybody’s body before the 1920s: chemicals that we know very little about.”

- Dr. Theo Colburn, renowned authority on endocrine disrupting chemicals in the environment
Figure 4.31: Town with falls. Source: Todd Berget

The TMDL Process:
Each TMDL differs because impairments to lakes, rivers and streams vary. However, the process of diagnosis, target reduction setting, and recommending strategies for repair is similar. The TMDL process asks the following questions:

There are three main sources of pollutants that influence water quality:

Point sources are discharges from an identifiable outlet such as municipal and public sewage discharge, stormwater outfalls, and industrial discharge.

Non-point sources are dispersed sources, including excess erosion from roads, agriculture and forestry activities, and construction, as well as unregulated storm water discharges, individual septic systems, and municipal sewer leakage.

Natural sources include sediment and nutrients from forest fires and naturally high concentrations of metals and chemicals from rock and soil that leach into surface and groundwater.

Point and non-point sources are the products of human influence on the landscape. The greatest percentage of stream and lake influences in Montana comes from non-point sources. The TMDL process is a problem-solving approach that results in a methodology for water quality improvement. The process helps to identify pollutants and ensure healthy water for current and future generations. The TMDL process must account for all land uses present in the watershed to characterize their pollutant contributions, all within resource and time constraints.

In the Flathead Watershed, the process incorporates a combination of watershed-scale hydrologic modeling, lake response models, and on-the-ground field efforts to further identify and quantify pollutant contributions from all significant sources. Used in combination, these methods yield the best available picture of the current water quality conditions and apparent reasons for problems. The resulting TMDL report provides an assessment of water quality conditions and targets for improvement, allocates reduction among different contributors, and provides a strategy for restoration. It does not impose new regulations or implement TMDLs, although it can recommend sources of technical assistance for implementation.

Water Quality Indicators
While rivers, streams, and lakes in the Flathead Watershed may seem pristine, there are water bodies that do not support or only partially support one or more of their “beneficial uses.” Beneficial uses are defined by state water quality statutes and include drinking water, agricultural and industrial uses, habitat for aquatic life, cold water fisheries, and recreation. Probable causes for impairment include nutrients, siltation, suspended solids, flow alteration, organic enrichment, algal growth, organic compounds known as polychlorinated biphenyls (PCB’s), metal, mercury, and noxious aquatic plants. Probable sources include runoff from development, old or poorly maintained septic systems, poor agricultural and timber harvest practices, and air pollution.

“Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in beer.”
- Dave Barry, Pulitzer Prize-winning columnist, humorist, and author

Because much of our water drains to Flathead Lake, the lake is a good indicator of the health of the rivers, streams, other lakes, and other waters that contribute to it. Flathead Lake remains one of the cleanest large lakes in the temperate regions of the world, but research shows that its water quality has been steadily declining. The University of Montana Flathead Lake Biological Station monitors water quality in Flathead Lake and reports its findings to the DEQ and to the Flathead Basin Commission.

Flathead Basin Commission
Flathead Lakers
Flathead Lake Biological Station
Montana Department of Environmental Quality
Water Quality Planning Bureau

Whitefish Lake Institute


For more information, send email to info@flatheadwatershed.org or info@flatheadcore.org.
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