HELENA (AP) - Gov. Judy Martz is pushing to renegotiate a 1921 international agreement that, according to a recent study, has let Canadian irrigators take more than their share of water from the St. Mary and Milk rivers.
Montana farmers in the Milk River Basin have been shortchanged about 90,000 acre-feet a year for the past half-century, the state study found. An acre-foot of water is 325,851 gallons.
The agreement has not been reviewed in 83 years, Martz noted.
Robert Boyles, a spokesman for Alberta Environment, the environmental agency of the Alberta provincial government, said Alberta officials believe the agreement is working fine and oppose the idea of changing it
Last April, Martz asked the International Joint Commission, the panel of three Canadians and three Americans that oversees such agreements, to revisit the 1921 agreement.
The commission has not decided whether to reopen the agreement, but will hold public meetings this summer in Havre, Malta and two communities in Canada, said Richard Moy, chief of the Water Management Bureau in Montana's Department of Natural Resources and Conservation.
The agreement provides for the United States and Canada to share equally in the waters of the two rivers, which would be considered one stream. The headwaters of both rivers are in Glacier National Park in Montana, and both flow north into Canada.
The Milk River later flows back into Montana north of Havre. From there, it runs east and forms the economic lifeline of Hi-Line agriculture all the way to Glasgow, Moy said.
The St. Mary Diversion, a series of structures on the plains east of Glacier Park, deposits some water from the fast-moving St. Mary River into the slower Milk.
About 140,000 acres of Montana farmland are irrigated with Milk River water, Moy said, and the crops grown there make up about 8 percent of Montana's agriculture economy.
Montana officials submitted an analysis last December to the international commission. It showed that Montana routinely gets less than its share of water because of a variety of factors, but largely because the Milk River routinely runs dry and the St. Mary rarely does.
The analysis shows that Montana farmers have been averaging only about 43 percent of the water, and as little as 37 percent in dry years.
Further complicating the matter, Moy said, is that when the 1921 agreement was signed, nobody was paying much attention to water rights held by American Indians. Several tribes have rights to water in both rivers, but only one, the Blackfeet Nation, has yet to settle with the state about exactly how much water the tribe is owed.
The Blackfeet claim, far older than the treaty or any other claims to the water, dates to 1855. Moy said the Blackfeet will eventually settle with the state and may decide to take their water.