Montana Department of Environmental Quality About Us Permitting & Operator Assistance Public Participation



Supplementary resources including documents, reports, frequently asked questions, and guidance. For additional information please visit the specific DEQ program page. To obtain records that are not available on the DEQ website please visit the Public Records Center.

Water Quality Library

The Water Quality Library was formed to support the mission and operations of the Montana DEQ's Water Quality Division by making water quality documents and publications available to the public. There are over 8,500 titles in the collection including books, reports, journal articles, and DVDs, covering subjects related to water quality including methodology, toxicology, soils, mining, nonpoint pollution, fish, forestry, and modeling.

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Clean Water Act Information Center (CWAIC)

Here you will find information about the quality of Montana's rivers, streams, and lakes in relation to Montana's Water Quality assessments. These assessments are derived from available statewide water monitoring data and information. The Clean Water Act Information Center also provides access to Montana's Water Quality Reports and List of Impaired Surface Waters, as well as online search and mapping tools.

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The federal Clean Water Act requires DEQ to assess Montana’s water quality and prepare a report every two years. The Montana Water Quality Report and List of Impaired Waters (known as the Integrated Report) combines reporting information for the Clean Water Act Section 305(b) assessment of water bodies and the Section 303(d) list of water bodies that do not meet water quality standards. Water bodies not meeting standards need pollution reduction studies, called Total Maximum Daily Loads (TMDLs). TMDLs also include plans to improve water quality to eventually meet standards.

When assessing surface water quality in Montana, DEQ is guided by the Beneficial Use Assessment Method for Montana’s Surface Waters. This document describes the framework used to assess state waters and to make the beneficial use support and water quality impairment decisions that are presented in the Water Quality Integrated Report.

DEQ assesses whether state surface waters are meeting applicable water quality standards for specific water quality characteristics, or parameters. If a waterbody is not meeting one or more water quality standards, DEQ considers the waterbody impaired and adds it to Montana’s list of impaired waters in the Water Quality Integrated Report. DEQ develops parameter-specific assessment methods which present the required data, analyses, and decision frameworks used to make these parameter-specific impairment listing decisions.

These documents and supporting files constitute the State of Montana's final Water Quality Integrated Report submission to the U.S. EPA for the given reporting cycle. This includes both the Section 303(d) List and Section 305(b) Report as required under the federal Clean Water Act.

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Montana classifies its waterbodies according to present and future beneficial uses they are expected to support (§ 75-5-301, MCA). This layer displays surface water bodies in Montana contained the NHD and their associated use class.

Go To The Use Class Map

Montana’s surface-water-use classification system bases class assignments primarily on water temperature, fish, and associated aquatic life. Each class has an associated beneficial use. A waterbody supports its beneficial uses when it meets the Water Quality Standards (WQS) established to protect those uses. A waterbody is impaired when any one of its WQS are violated.

Determining whether or not a specific use is supported is independent of all other designated uses. For example, a waterbody may partially support aquatic life because of excess nutrients, not support drinking water because of arsenic, but fully support agriculture and industrial uses. Classes A, B, and C are the three most common. Class I is a temporary category assigned to three streams that were grossly impaired when the system was established. Classes A-Closed and A-1 are considered high quality, the principal beneficial use of which is public water supply. The A-Closed class may invoke watershed protection and use restrictions to protect drinking water. Classes B and C each have subsections according to whether they support coldwater or warmwater aquatic life. B-1, B-2, C-1, and C-2 support coldwater aquatic life; B-3 and C-3 support warmwater aquatic life. B and C waters have nearly identical use classifications, but B waters specify drinking water as a beneficial use whereas C waters do not. C-3 streams are suitable for warmwater aquatic life and recreation. Because these streams often contain naturally high total dissolved solids (salinity), their quality is marginal for drinking and agricultural and industrial uses.

In August 2003 Montana added four additional classes: D, E, F, and G. The classes include ephemeral streams (E-1, E-2), ditches (D-1, D-2), seasonal or semi-permanent lakes and ponds (E-3, E-4, E-5), and waters with low or sporadic flow (F-1). G-1 waters must be maintained for watering wildlife and livestock and supporting secondary contact recreation and aquatic life, not including fish. These waters are marginally suitable for irrigation after treatment or with mitigation measures and includes “holding water” from coal bed methane development. Note: The classification system designated uses for waterbodies as present at the time of classification in 1955.

Waterbodies may now have other realized uses that are not officially designated. In such cases, a waterbody may be reclassified to officially recognize these other uses. Conversely, designated uses cannot be removed from a waterbody without a formal Use Attainability Analysis and approval under rulemaking by the Montana Board of Environmental Review. Streams forming the boundary of Indian Reservations are coded as State of Montana (SOM) waters for practical reasons related to enforcing Federal and Montana water quality standards. In some cases meanders, canals, and ditches that transect the boundary and then reconnect with a border stream are also coded as SOM waters even when they are located in part or entirely within the Indian Reservation. As a result of this coding protocol,

If you use the "select by location" procedure to identify streams that are completely within one of the reservations, the resulting selected records may include a small number of streams coded as SOM in the "Authority Entity" field. This is not a mistake and needs to be kept in mind when interpreting selection results. Streams that are not parallel to or located on a border but that cross into and are entirely within an Indian Reservation retain the use class as designated by the ARM description for the watershed they are part of but they are designated as "Not State Jurisdiction" or NSJ in the event table's "Jurisdiction" field and the name of the tribe is recorded in the "Authority Entity" field. The name of the reservation is recorded in the "Area Name" field. Streams that are not parallel to or located on a border but that cross into and are entirely within national parks, wilderness areas or primitive areas are assigned a use class of A-1 as specified by ARM Title 17 Chapter 30 Subchapter 614. The name of the park, primitive area, or wilderness area is recorded in the "Area Name" field of the event table. As a consequence, a stream crossing a border will likely have different use classes on either side of the border.

Advisory Councils

The Nutrient Work Group is an advisory work group, convened by the Department of Environmental Quality, representing publicly owned and privately owned point sources of pollution, nonpoint sources of pollution, and other interested parties that will advise the Department on the implementation of nutrient water quality standard together with associated economic impacts. Please review the Nutrient Work Group Charter for additional information.

Staff Contact: Christina Staten (406) 444-2836

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Submit Comments or Questions

Thank you for your interest in the nutrient standards process. The 2021 Legislature passed, and Governor Gianforte signed into law, Senate Bill 358. The new law requires DEQ to adopt rules to implement its narrative nutrient standards and provides a transition from Montana’s existing numeric nutrient standards and variance approach to a new narrative standards approach.

During this process, DEQ will work with the Nutrient Work Group, which includes the EPA and representatives from various interest groups. The timeline for creating the new narrative implementation is March 2022.

DEQ will assist permittees in understanding the narrative nutrient standards and will develop guidance documents and adaptive management plans to help with the transition.

While the process involves the Nutrient Work Group, DEQ values public engagement. Listening sessions will be held a few times throughout the process to answer questions and listen to comments from the public. To submit a question, please fill out the form below. Questions will be addressed at the next listening session. If questions are submitted after planned listening sessions, DEQ will respond directly to your question via email.

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Next Meeting

Type Date Time Location Agenda
Nutrient Work Group July 28, 2021 9:00 - 11:00 a.m. DNRC Montana Room and via Zoom Agenda
Technical Subcommittee August 3, 2021 1:30 - 3:30 p.m. DEQ Room 45 and via Zoom


Meeting Calendar

Agendas, Meeting Summaries and Materials

Nutrient Work Group Members

Technical Subcommittee Members

Member Resources

Pre-2020 Meeting Materials and Summaries

The Statewide TMDL Advisory Group (STAG) is authorized under section 75-5-702(9) of the Montana Water Quality Act. The STAG serves in an advisory capacity to the Department on topics such as TMDL development priorities, water quality assessment methods, water quality data management, and TMDL implementation monitoring. The fourteen member group represents a broad base of water related interest groups in Montana.  The groups represented are livestock-oriented agriculture, farming-oriented agriculture, conservation or environmental interest, water-based recreationists, the forestry industry, municipalities, point source dischargers, mining, federal land management agencies, state trust land management agencies, supervisors of soil and water conservation districts for counties both west and east of the continental divide, the hydroelectric industry, and fishing related businesses.

The Department selects members of the advisory group by soliciting nominations from each interest group. The nominees must agree on a single nominee, which is then appointed to the STAG by the DEQ Director. STAG members serve a term limit of two years, but there are no limits on the number of terms a member may serve if they are renominated by their interest group at the end of their term.

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Next Meeting

Thursday, August 26, 2021

10:00 a.m.

Agenda with Zoom Information to be Posted in August

The Subdivision and Development Advisory Council’s mission is to act as a liaison between DEQ, counties and sanitarians, and the public as part of the Department’s continual improvement process focused on improving subdivision and development related processes and policies while protecting public health and the environment.  The Subdivision and Development Advisory Council’s work is guided by the policies set out under the Water Quality Act MCA 75-5-101 and the Sanitation in Subdivisions MCA 76-4-101.

Meeting Agendas

SDAC Members

The Water Pollution Control Advisory Council represents a diverse array of Montana interests and plays an important role in formulating Montana's water quality policy. Council members are appointed by the Governor and serve in an advisory capacity to the Department by furnishing advice, gathering information, and making recommendations. The Council also reviews and advises the Department on draft administrative rules prior to their consideration by the Board of Environmental Review. WPCAC is authorized under section 2-15-2107 of the Montana Code Annotated.

Staff Contact: Darryl Barton (406) 444-0014

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Next Meeting

Date Time Location Agenda
TBA   Via Telephone & Zoom

Agendas, Minutes and Presentations

WPCAC Members

Members Resources

The Water and Wastewater Operators' Advisory Council provides program stakeholder review functions.  The council is appointed by the governor and is comprised of seven members (2-15-2105, Montana Code Annotated).  The members are water and wastewater operators, representative of a municipality, and faculty member of a university, and a department representative.

Council Members

Name Position/Representing
John Alston City of Bozeman
Ronald Edwards Bozeman
Leo Malinak Town of Valier
Amy Steinmetz PWS Bureau Chief - DEQ Rep
Andrew Loudermilk Bigfork County
Craig Woolard Montana State University - Bozeman
Logan McInnis Missoula Water

DEQ Staff Contacts

Name Title
Greg Olsen Operator Certification Supervisor
Reta Therriault Operator Certification Technician
Jen VandenBos Operator Certification Technician

Council Meeting Minutes

Statutes, Rules, and Regulations

Circular Titles/Descriptions

  • DEQ 1 - Standards for Water Works
  • DEQ 2 - Design Standards for Wastewater Facilities
  • DEQ 3 - Standards for Small Water Systems
  • DEQ 4 - Montana Standards for On-Site Subsurface Sewage Treatment Systems 2013 Edition
  • DEQ 7 - Montana Numeric Water Quality Standards
  • DEQ 8 - Montana Standards for Subdivision Storm Drainage
  • DEQ 10 - Standards for the Development of Springs for Public Water Systems
  • DEQ 11 - Montana Standards for Development of Springs for Individual and Shared Non-Public Systems
  • DEQ 12A - Montana Base Numeric Nutrient Standards
  • DEQ 12B - Nutrient Standards Variances
  • DEQ 13 - Montana Policy for Nutrient Trading
  • DEQ 16 - Standards for Hauled Water Cisterns (Water Storage Tanks) for Non-Community Public Systems
  • DEQ 17 - Montana Standards for Cisterns (Water Storage Tanks) for Individual Non-Public Systems
  • PWS 5 - Groundwater under the Direct Influence of Surface Water
  • PWS 6 - Source Water Protection Delineation
Program/Responsibility DEQ PWS
Coal Bed Methane                        
Discharge Permits                      
Drinking Water Supply            
Facility Design Standards                            
Ground Water Remediation                            
Mixing Zones                          
Water Quality Monitoring                          
Nonpoint Source                        
Source Water Protection                          
TMDL Program                      
Wastewater Systems                          
Water Pollution Control SRF                          
Water/Wastewater Operator Certification                            
National Drinking Water Regulations
Public Water and Sewage Systems
Consumer Confidence Report Rule
Lead and Copper Rule
Disinfectant Byproducts Rule
Montana Chlorination Rule
Surface Water Treatment Rule
Total Coliform Rule
Water Treatment Operators
Drinking Water State Revolving Fund

General Resources

Total Maximum Daily Load Maps & Documents

TMDL Project Map

*TMDLs are specific to a waterbody segment - pollutant combination. Some project areas with completed TMDLs may still require TMDL development for additional waterbody-pollutant combinations. Priority areas are subject to change.

Click here for a more detailed PDF version of this map

Final TMDL Documents

Choose a river basin below to view a list of associated TMDL documents.

Note: Dates next to each TMDL document are the EPA approval dates. Some documents may have had edits made after this date and will include a detailed listing of the changes. Always check DEQ's website for the most recent document version.

Visit the Lakes, Streams and Wetlands Program page to view final TMDL documents listed alphabetically in smaller file sizes with appendices and attachments as separate files


Bitterroot Watershed
Blackfoot River Watershed
Bobtail Creek
Clark Fork River
Flathead River Basin
Flint Creek Watershed
Little Blackfoot
Ninemile Creek
Prospect Creek
Rock Creek
St Regis
Swan Lake
Approved TMDL Documents TMDL Implementation Evaulations
Thompson River Watershed
Tobacco River Watershed

Upper Missouri

Beaverhead River Watershed
Big Hole River Watershed
Boulder-Elkhorn Project Area
Gallatin River Watershed
Jefferson River Watershed
Lake Helena Watershed
Madison River Watershed
Red Rock
Project Website
Sheep Creek
Approved TMDL Documents Project Website

Lower Missouri


Use EPA's Enforcement and Compliance History Online website to search for facilities in your community to assess their compliance with environmental regulations. You can use ECHO to:

  • Search for Facilities
  • Investigate Pollution Sources
  • Search for EPA Criminal and Civil Enforcement Cases
  • Examine and Create Enforcement-Related Maps
  • Analyze Trends in Compliance and Enforcement Data
  • Explore your State's Performance

Please Note: The data online is provided as a public resource and does not always reflect the most up to date information.

Get Involved

To make it easier for you to find an opportunity to get involved, notices, comment opportunities, and upcoming meetings associated with Water will be shared here. To see all opportunities go to Public Participation.