The USGS serves as the lead agency for the United States to measure and apportion natural flows of the St. Mary and Milk Rivers according to the Boundary Waters Treaty of 1909 and the International Joint Commission Order of 1921. The division of water between the United States and Canada is overseen by the Accredited Officers of the St. Mary and Milk Rivers, who are appointed by their respective governments.
The United States’ share of water is primarily used by the U.S Bureau of Reclamation - Milk River Project, which diverts St. Mary River water into the Milk River watershed.
The project, locally known as “the lifeline to the highline,” meets the needs of residents and industry along the Northern Tier of Montana to:
- Irrigate approximately 121,000 acres;
- Supply water to municipalities and domestic users; and
- Fulfill Tribal water rights.
Project Objectives
- Measure and report hydrologic data from the St. Mary and Milk Rivers flowing within the United States.
- Collaborate with Water Survey Canada and Provincial Government officials to apportion water according the 1909 Treaty and International Joint Commission Order of 1921.
- Address technical challenges and modernize apportionment methodology and techniques.
Publications
Important links
International Joint Commission
Current Streamflow Conditions in Montana
- Overview
The USGS serves as the lead agency for the United States to measure and apportion natural flows of the St. Mary and Milk Rivers according to the Boundary Waters Treaty of 1909 and the International Joint Commission Order of 1921. The division of water between the United States and Canada is overseen by the Accredited Officers of the St. Mary and Milk Rivers, who are appointed by their respective governments.
Chief Mountain The United States’ share of water is primarily used by the U.S Bureau of Reclamation - Milk River Project, which diverts St. Mary River water into the Milk River watershed.
The project, locally known as “the lifeline to the highline,” meets the needs of residents and industry along the Northern Tier of Montana to:
- Irrigate approximately 121,000 acres;
- Supply water to municipalities and domestic users; and
- Fulfill Tribal water rights.
Project Objectives
- Measure and report hydrologic data from the St. Mary and Milk Rivers flowing within the United States.
- Collaborate with Water Survey Canada and Provincial Government officials to apportion water according the 1909 Treaty and International Joint Commission Order of 1921.
- Address technical challenges and modernize apportionment methodology and techniques.
International Hydrological Studies Map Publications
Important links
International Joint Commission
Current Streamflow Conditions in Montana