85-20-1801 MCA

This compact between United States and the State of Montana settles for all time the United States’ federal reserved water right claims for the Upper Missouri River Breaks National Monument. The ratified compact subordinates the United States’ 2001 priority date to June 1, 2012; quantifies an instream flow right of 160 cfs in the Judith River and 5 cfs in Arrow Creek, respectively; institutes an on-stream impoundment limitation; and requires ramping of large new diversions. The final compact is the product of a year of settlement negotiations between the U.S. Department of Interior and the State of Montana. The negotiated compact was ratified by the 2013 Montana Legislature and signed by Governor Steve Bullock. The Department of the Interior and the Department of Justice have also approved the compact (Effective Date: June 1, 2015). The Montana Water Court issued the compact Preliminary Decree in 2015 and an “Order Approving” in April 2016.

Compact Summary


The key provisions of the Compact are:

  1. Protection of all existing water rights arising under State law with a priority date earlier than June 1, 2012. All of these existing rights are senior in priority to any rights granted to the BLM under this compact.
  2. No reduction in the amount of water available for future development in the Judith Basin as a result of this compact.
  3. Continued exception to permitting for domestic wells, stock ponds, and other uses that meet the requirements for exception to permitting as listed in 85-2-306 MCA. These uses will not be subject to call by the BLM under the specifications of this compact.
  4. Water Right: In settlement of the Monument’s Reserved Water Right claim, a water right is granted on both the Judith River and Arrow Creek.
    1. Judith River: The Judith River water right is in the amount of 160 cubic feet per second (cfs) measured at the USGS gaging station near the confluence of the Judith River with the Missouri River. The period of use is January 1 through December 31 of each year. This right shall run concurrently and junior in priority to a Montana Fish, Wildlife & Parks right for the same source, flow rate, and period of use.
    2. Arrow Creek: The Arrow Creek water right is in the amount of 5 cfs measured where the Monument boundary intersects with Arrow Creek. The period of use is March 1 through July 31 of each year. A proportionally lower flow rate at the may be determined at an alternate measurement point.
  5. Priority Date: The reserved water right will have a priority date of January 17, 2001, but this reserved right will be subordinate to state-based permits with a priority date before June 1, 2012.
  6. Restriction on Mainstem Impoundments: New mainstem impoundments under this Compact not otherwise excepted from permitting requirements under Montana law will not be permitted on the reaches of the Judith River and Arrow Creek depicted in the map linked at the bottom of this page. Off-stream impoundments will continue to be permitted under DNRC permitting procedure.
  7. Ramped Diversion Requirement: : Flows on both the Judith River and Arrow Creek that have not already been appropriated as of the date of this Compact will be available for future state-based development, subject to the Reserved Water Right and applicable permit restrictions. New permits issued after the date on which this Compact is ratified (6/1/2015) will be subject to a ramped diversion requirement for diversions greater than 20 cfs capacity. Direct from source diversions from the Judith River and Arrow Creek that have a diversion capacity greater than 20 cfs will be allowed an increase in diverted water of no more than 20cfs per 24 hour period.


Compact Appendices:
  • Appendix 1 - Judith River General Abstract of Water Right Claims
  • Appendix 2 - Arrow Creek General Abstract of Water Right Claims