Water is an important resource to everyone, everywhere. The waters of Montana are utilized diversely, and consequently many Montanans place exceptionally high value on their water resources. Montana uses its water for fishery habitats, recreation, irrigation, power generation and livestock, as well as for everyday domestic tasks. These are just a few reasons why Montana strives to keep its lakes and streams free of pollutants. Montana values its water resources to the point that the results of a state-wide voter referendum allowed the Montana Department of Environmental Quality to set some of the most stringent water quality standards for surface waters of any state in the nation. Consequently, a principle goal of the department is to protect and preserve Montana's water resources. This goal could not possibly be achieved if the importance of mechanisms like the TMDL (total maximum daily load) process were not realized when they were.

     The following article outlines the TMDL process, which is currently one of the most effective ways for achieving and maintaining acceptable water quality standards. We then provide an introduction to watershed planning process using a case study of Mill Coulee Creek, a small watershed in north central Montana. The TMDL process, which is national in scope, is being used in Montana to assess existing water quality conditions and define landowner and stakeholder approaches to making changes or improvements in existing water resources to achieve commonly agreed to goals for water quality.

     In 1972 the Environmental Protection Agency passed the landmark Clean Water Act, which created a federal program designed to achieve the goals of both protecting and restoring the physical, chemical, and biological integrity of our nation's waters. Since then, many provisions and advances which reflect our knowledge of water quality have been made. In 1987, the Water Quality Act authorized individual states to bring water quality issues to a more local level by allowing each state to establish its own water quality standards. Another provision, stated in section 305(b) of the Clean Water Act, has mandated that each state prepare a water quality inventory every two years and that a list of impaired waters in the state be submitted as a 303(d) list. This so-called "303(d) list" is well known by individuals involved in water quality management and it has become the focus of a national effort to identify, classify, characterize and where necessary, improve our nation's water resources. By making water quality a local responsibility, the benefit of maintaining high water quality standards becomes a daily reward. Collectively, the steps taken to identify and restore the impaired waters are known as the TMDL process.

     TMDL (total maximum daily load) is the maximum amount of any pollutant, contaminant, or impairment that can enter a body of water before the quality of the water is deemed unfit for its designated uses. Hence, TMDL is like a threshold, target, or upper limit. TMDL's must be established for both point source and nonpoint source pollutants and all parameters of water quality including chemical, physical, and biological factors are considered. Point source pollution and nonpoint source pollution differ as a consequence of the way an impairment enters a waterbody. A point source pollutant can be traced to the specific, discernable location where it enters the water. Nonpoint source pollutants, rather, enter a body of water from many diffuse sources. Urban, agricultural, and industrial runoff are the main causes of nonpoint source pollution. It is, therefore, easy to begin to understand how difficult the TMDL process can become. Montana is currently one of the few states that has established TMDL regulations that far exceed the requirements set by the EPA. In fact, as a consequence of legal action initiated by conservation groups in Montana, the Montana Department of Environmental Quality is under relatively strict guidelines and deadlines to complete the TMDL process throughout Montana. The TMDL process can be summarized as the following:

     Identifying the impaired waters: If you want to learn more about the current stage of the TMDL process in Montana and the target dates for completion of the TMDL process for Montana's water bodies, visit the Department of Environmental Quality web site which contains information regarding both past and present Montana 303(d) lists. Needless to say, identifying impaired bodies of water has proven to be a difficult, but manageable task in Montana.

     Prioritizing the list: What constitutes an impairment? That depends on the intended or designated use of the water body. An impairment means that the water can't support a designated use, such as fishery, recreation, irrigation, or public drinking supply. The causes are varied and are often associated with land use practices within the watershed, or area of land from which water is draining to make up the water body.

     The grouping of impaired waters into low, medium, and high priority for the TMDL process is based upon the following thirteen specific ranking factors:

1. Impact to human health and aquatic life.
2. Character of pollutant and severity of noncompliance.
3. Beneficial use of the waterbody.
4. Size of the waterbody.
5. Extent of natural factors leading to the impairment.
6. Whether the waterbody is a high quality resource in the early stages of degradation.
7. Degree of interest and public support.
8. Immediate programmatic needs.
9. Availability of technology and resources to correct the problem.
10. Whether actions or voluntary programs are currently in place to control the problem.
11. Recreational, economic or aesthetic importance of the waterbody.
12. State priorities and policies including the restoration of native fish, when important.
13. Judicial orders or lawsuits.

     The high priority list consists of waters that are targeted for TMDL development within the next two years, or before the next 303(d) list is published. Medium and low priority waters usually require additional assessment and/or monitoring before further action can be taken.

     Developing TMDL's: Once the identification and priority ranking of impaired waters is complete, then the state must develop TMDL's that meet these physical, chemical, and biological water quality standards. How and where the pollutant enters the water does not matter as both point source and nonpoint source pollutants are targetted for management. In those sitautions where a TMDL cannot be accurately placed upon a nonpoint source pollutant, an educated estimate will be deemed sufficient.

     Strategies to achieve TMDL's: The final step of the TMDL process insures that the water quality standards are met and maintained. This is done by developing a strategy to reduce impairment and then performing a follow up assessment or designing a monitoring program. At this stage, building upon community development, agricultural programming, and watershed partnerships becomes crucial. Management practices along any stream corridor or lakeside are effective only when all who have contact with the water have an educated respect for its integrity. It is for this reason that the Montana State University Extension Service strives to educate citizens as well as landowners about point source and nonpoint source pollution in our state's waterbodies.

     Now that the TMDL process has been introduced and both point source and nonpoint source pollutants have been defined, we invite you to learn more about this process in detail by following our progress along a stream that may very well be right out your back door! Please keep in mind that the TMDL process is an evolving process which is still being defined. The objective is pretty clear - it's just that we don't know the exact way to go about achieving that goal in all cases. The Mill Coulee model is just one example of an approach. In this particular case, we had a pretty well defined problem - or perception of a problem. The Mill Coulee project provides one model and some guidance about how we went about addressing this issue. Future effort will deal with reporting on what we have accomplished.

*This article was written with the intent of introducing and summarizing the TMDL process. Further details can be found at:

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