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Conservation > Fisheries Management > Habitat > Water Management Instream Flows

Montana's water law currently provides several mechanisms to directly protect or enhance instream flows or water levels. Provision in law that protect instream flows include:

  1. Pre 1973 statutory directive or authorization to create instream water right on certain key streams. (These existing water rights include "Murphy Rights", "Public Recreational Claims" and Use Rights.), [Learn more]

  2. Post 1973 rights created through the State's Water Reservation process,

  3. Water Leasing, (The Conversions of existing diversionary water rights to instream flow purposes.)

  4. Purchase or service contracts for water delivery from new or existing water storage projects.


Other mechanisms that help maintain stream flow conditions:

  1. Future Fishery Projects, and

  2. Designation of "Closed Basin" watersheds.


Instream Flow Methods

Murphy Water rights

The Montana legislature recognized the value of leaving water in streams for fish and wildlife purposes in 1969. That year they pass an instream flow protections bill that became law, 89-901 RCM. The resulting statute directed the Fish and Game Commission to make a filed appropriation on the unappropirated waters of twelve blue ribbon streams. These water rights have become known as Murphy Rights, named for the bill's sponsor, James E. Murphy.

The Montana Fish and Game Commission was given the authority by the Legislature to file for water rights on the unappropriated waters of 12 streams to maintain stream flows necessary for the preservation of fish and wildlife habitat (Section 89-901 (2), RCM 1947).


Murphy Right Streams
  • Big Spring Creek in Fergus County, from its mouth to the state fish hatchery.

  • Blackfoot River in Missoula and Powell Counties, from its mouth to the mouth of its North Fork.

  • Flathead River in Flathead County, from its mouth to the Canadian border on the North Fork.

  • Gallatin River in Gallatin County from its mouth to the junction of the East Fork.

  • West Gallatin River in Gallatin County from the Beck and Border ditch intake to Yellowstone National Park boundary.

  • Madison River in Madison and Gallatin County from its mouth to Hebgen Dam.

  • Missouri River in Lewis and Clark, Broadwater and Cascade Counties from its junction with Smith River to Toston Dam.

  • Rock Creek in Granite and Missoula Counties from its mouth to the junction of the East and West Forks of Rock Creek.

  • Smith River in Cascade and Meagher Counties from the mouth of Hound Creek to the Fort Logan bridge.

  • Yellowstone River in Stillwater, Sweetgrass and Park Counties from the North-South Carbon Stillwater County lines to where it leaves Yellowstone National Park boundary.

  • Middle Fork Flathead River in Flathead County from its mouth to the mouth of Cox Creek.

  • South Fork Flathead River in Flathead and Powell Counties from its mouth at Hungry Horse Reservoir to its source at the junction of Danaher and Youngs Creeks.

Public Recreation Claims

FWP has also filed Statements of Claim for Existing Water Right –Recreation for "public recreational use" in the BeaverheadBitterroot and Blackfoot/Clearwater drainages. These claims are grounded in the legislature's direction to FWP in the 1979 legislative session. That year, Senate Bill 76, among other things, conferred on FWP the responsibility to represent the public for the purpose of establishing any prior and existing public recreation uses in existing right determinations. (See MCA 85-2-223 ) Often the flows and volumes of these FWP claims are linked to fish habitat needs, and the recreational use asserted is primarily fishing and recreational floating. Priority dates for these water rights are very junior (typically near 1970). The validity of these recreational use claims has yet to be fully evaluated in Montana's general stream adjudication.



The concept of state based water reservation was established in the Montana Water Use Act of 1973. Reservations provide an avenue for public entities to seek water for future use or to protect in stream flows or water levels. (See MCA 85-2-316) Instream flow water rights (reservations) have been granted for more than seven-hundred river and stream reaches and are held for the Montanan's by FWP.

  • Yellowstone Basin

  • Upper Missouri River

  • Lower Missouri River



The leasing of a water right for instream flow is a voluntary agreement and contract between willing parties. Private parties can develop the terms of a water right lease or exchange between themselves. However before any agreement that moves water or changes is use, place of use or purpose of use is implemented that Change of Use is subject to administrative and public review in a Department of Natural Resources and Conservation proceedings. The following booklet is a brief introduction to some the basic concepts a water user should consider.

Leasing Reports



Montana water law has long view the storage of water for some beneficial use to a legal diversionary right. Such rights have a definable diversion and control of water. Montana water law has long recognized the practice of transporting stored water from the reservoir to its place of use. Therefore, using stored water to augment stream flows is a practice commonly recognized with many federal storage projects in Montana.

Basin Closure Protection — Closed basin designation is a statutory process defined and governed by MCA 85-2-319 , as "Permit Action in Highly Appropriated Basins or Sub basins". The legislature may be law may preclude permit applications (certain new water rights) or the Department of Natural Resources and Conservation may, by rule, reject permit application of modify or condition permits already issued.


Judical Determinations

FWP has asserted pre-1973 water rights for instream flow and fishery use based on intensive pre-1973 management and restoration activities concentrated on a given stream of stream reach. Some of these water rights have been examined by the Montana Water Court and been subject to and up-held in court decisions in, at least, the first stages of Montana General Stream Adjudication.These adjudication instream flow rights include:

  • Ashley Creek

  • Tobacco River

  • Young Creek