Hangman (Latah) Creek
Water Quality Improvement/Total Maximum Daily Load (TMDL) Project

More on tMDLs and Hangman Creek Project

Public concern about water pollution in the early 1970s led to the enactment of the Federal Water Pollution Control Act in 1972. This act was amended in 1977 and is now commonly known as the Clean Water Act (CWA). The CWA establishes the structure for regulating polluting discharges to surface waters and sets water quality standards for all surface water contaminants. Water quality standards are a set numeric or narrative limits on various pollutants established to ensure that water bodies are able to support beneficial uses such as agriculture, drinking water, recreation, industrial uses and aquatic habitat.

Section 303(d) of the Clean Water Act requires Washington State to prepare a list of all surface water in the state for which beneficial uses of water are impaired by pollutants. The Washington State Department of Ecology (Ecology) is responsible for developing this list. Ecology's assessment of which waters to place on the 303(d) list is guided by federal laws, state water quality standards, and the State's 303(d) policies. Waters placed on the 303(d) list require the preparation of Water Quality Improvement Plans, commonly known as Total Maximum Daily Loads (TMDLs).

What is a TMDL?

Total Maximum Daily Load (TMDL) is a term used to describe the amount of pollution a stream can receive and still meet federal and state water quality standards. Water Quality Improvement Plans, commonly known as TMDLs, are required for water bodies that do not meet the standards.

TMDL plans identify the maximum amount of a pollutant that is allowed into a water body so as not to impair the uses of the water. A TMDL considers point sources such as residential, municipal, or industrial discharges and non-point sources such as residential, urban, or agricultural runoff. The plans identify the type and source of each pollutant and typically allocate the allowable pollutant load among the various pollution sources. In addition, the plans identify management strategies for addressing all sources of pollution. These plans, developed in cooperation with local residents, are a key tool in guiding the clean up of polluted waters.

What are the mandated elements of a TMDL?

A TMDL is required under the Clean Water Act and its implementing regulations to contain the following 7 elements:

• be developed to meet the applicable water quality standard
• contain a waste load allocation for permitted point sources, a load allocation for nonpoint (or diffuse) sources
• contain a margin of safety to account for uncertainties in TMDL development
• be developed for critical stream conditions
• consider seasonal variation
• consider background contributions
• be subject to public participation

TMDLs must also contain reasonable assurances for implementation.

How does Washington determine what is an “Impaired Water”?

Through water quality monitoring and assessment (i.e. comparing the monitoring data to the applicable water quality standards), the Washington State Department of Ecology (WDOE) determines whether a water body is impaired. Every even numbered year, Washington submits a list of the waters found to be impaired, the 303(d) list of impaired waters, to the Environmental Protection Agency. Currently, over 700 waters are listed as impaired in Washington State.

Visit DOE’s Water Quality Assessment website for more information:
http://www.ecy.wa.gov/programs/wq/303d/2002/summary_info.html

How did the Hangman Creek project get started?

Hangman Creek was identified on the 1998 303(d) list as being impaired by several pollutants.

In 2004, the Spokane County Conservation District (SCCD) applied for and was awarded a grant to develop the water quality improvement plan or total maximum daily load (TMDL) for the Hangman Creek watershed.

What are the water quality problems in Hangman (Latah) Creek?

Past and current land uses within the watershed are varied, and contribute to the problems. Issues such as stormwater runoff, sedimentation, stream bank erosion, water rights, instream flows, spawning habitat (cold water fisheries), urban development, wetland destruction, and agricultural and forestry practices are all major concerns for the area. Specifically, Hangman Creek was identified on the 1998 303(d) list for not achieving State water quality standards for fecal coliform, dissolved oxygen, pH, and temperature. Recent monitoring has identified several other water quality problems not acknowledged by the 303(d) list (sediment load, turbidity, ammonia, low flows, and total phosphorus).

How will the public participate in TMDL development?

A series of meetings are being held. The first meetings were designed to inform the public about the impairment, the TMDL process, and obtain public comment. Subsequent meetings are being held to discuss the on-going TMDL study, including pollutant sources and amounts and the status of the modeling work. The Watershed Advisory Group is meeting regularly to develop strategies to reduce the amount of pollution in the streams. When their work is complete, additional meetings will present the draft TMDL study, including reduction targets, for public review and comment prior to submittal to EPA. Public meetings will be advertised in local newspapers, through direct mailings, on the SCCD website, and in the North Palouse Journal.

What kind of input can stakeholders provide during the process?

Public participation is important because landowners know much of the information needed to help clean up the stream. Such information can be the location of public sewers, septic systems and straight pipes as well as the condition of the septic systems. Other information can be the confirmation of livestock and wildlife numbers and locations in the area. Stakeholders are encouraged to provide input into the study process so that the final report is as accurate as possible.

What happens after the TMDL Study is complete?

The TMDL Study will be submitted to EPA where they will have 30 days to review and approve the TMDL. Then a TMDL Implementation Plan will be developed to bring the impaired water body up to standards. This plan is required by the Memorandum of Agreement between Ecology, EPA and the litigants. The Implementation Plan will include a schedule of actions, costs, and monitoring. Implementation Plan development typically starts immediately after EPA approval and must be completed within one year.

How will the TMDL be implemented?

The WDOE and the SCCD anticipate the non-point source TMDLs to be implemented through Best Management Practices (BMPs) and expect that implementation will occur in stages. The benefits of staged implementation are:

• As stream monitoring continues to occur, it allows for water quality improvements to be recorded as they are being achieved;
• It provides a measure of quality control, given the uncertainties which exist in any model;
• It provides a mechanism for developing public support;
• It helps to ensure the most cost effective practices are implemented initially; and
• It allows for the evaluation of the adequacy of the TMDL in achieving the water quality standard. 

Implementation will occur through a variety of means, including voluntary practices adopted by landowners and through projects conducted by the Conservation District.

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