01/16/2006 — Idaho has recognized the limits of the Snake River since 1985.
That July 1, a minimum stream flow of 3,900 cubic feet per second was established. By comparison, Boise doesn't encourage floating on the Boise River when flows exceed 1,500 cfs. If the flow of the Snake River drops significantly below that number at a monitoring gauge at Murphy, anyone who established a water right after July 1, 1985, must shut down their pumps.
The minimum flow was set after an Idaho Supreme Court decision on March 31, 1983, which changed the way the state manages its water. The court ruled that Idaho Power Co. had a right to 8,200 cubic feet per second of Snake River flows.
Water in the Snake River and all state waterways is a public resource, owned by the state. However, people and companies own the right to use it. For decades, water disputes were primarily between farmers.
But after more than 100 years of agricultural development, first of surface water and later of groundwater, the flows in the Snake River had dropped enough that the hydroelectric power plants Idaho Power had built were not meeting the state's demand for electricity. That's because too little water was flowing through the plants' turbines.
The utility tried to get approval of a coal-fired power plant between Mountain Home and Boise to meet the demand. But critics said using the more expensive coal-fired power could put many farmers out of business because they wouldn't be able to afford the electricity needed to pump water for irrigation. Ironically, the same farmers whose pumping from the river and the aquifer threatened the utility's hydropower operation would have been hurt most by higher electricity rates.
A group of these farmers and other customers sued the company, saying their power rates were going up because the company wasn't defending its rights to the water needed for hydropower. They won, and Idaho Power was forced to sue.
When Idaho Power won, it placed the electric utility in control of the water irrigating millions of acres of crops in southern Idaho. That triggered a political crisis.
In 1984, Gov. John Evans, Attorney General Jim Jones and Idaho Power President Jim Bruce hammered out a settlement called the Swan Falls Agreement. The agreement reduced the minimum flow to 3,900 cfs, made it harder to approve new water diversions upstream from the Swan Falls Dam, and set in motion the legal review of all of the water rights in the Snake River basin. This review, called the Snake River Adjudication, has been working its way through state courts since 1987.
Without the agreement, farmers and other water users would have had to pay Idaho Power for water they had previously had a right to use.
The agreement put the state back in control of the water and kept it in the hands of those holding existing water rights.
"Instead of the state being in a position to parcel water out on a relatively inexpensive basis, Idaho Power would have been the entity parceling it out and the cost of water rights would have been substantially greater," said Jones, now an Idaho Supreme Court justice.
Randy Stapilus, editor of the Idaho Public Affairs Digest, a political newsletter, said the decision and the agreement were a turning point in Idaho history.
"The Swan Falls decision forced us to come to grips with the fact we do have a limited resource here," Stapilus said.
The agreement ensures Idaho Power has a source of water for all of its Snake River hydroelectric plants. It also protects flows for fish, recreation and wildlife.
"Without the agreement, it's conceivable the flows could have gone to zero, and we would have had to make up the loss of power with other sources," said Jeff Beaman, Idaho Power director of corporate communications.
So here's what could happen if the Snake River drops below the Swan Falls minimum stream flow, as it came close to doing in 2003 and 2004:
At least 300 water rights, affecting 25,000 acres of irrigated farmland, could be forced to shut down. They all began using water after 1985, and their rights to the water are junior to the 1985 minimum stream flow right. There may be many more people who sunk wells after 1985 — more than 13,000 by one estimate — who also would be forced to shut down.
For the water users on the cusp, most have temporary alternatives to make up for the water they must leave in the river.
For example, J.R. Simplot has an 80-acre field near C.J. Strike Reservoir that has a right to divert 1.6 cubic feet per second of water from the Snake for irrigation. If that pump is shut down, the company can transfer a water right from a nearby field, said Fred Zerza, a Simplot spokesman.
The Swan Falls minimum could curtail the city of Glenns Ferry's right to divert 1 cubic foot per second for its water supply that has a 1996 priority date. However, the city has other senior rights that meet its current needs.
The Swan Falls agreement also called for developing water markets so farmers could sell their water to industry and others for a higher price. Those markets have been severely limited in Idaho by agriculture interests that seek to keep the price of water low so it is affordable for farmers.
