February 10, 2021
The question of how much the Icicle Peshastin Irrigation District has relinquished water rights at Eightmile Lake is moving toward center stage.
Both dam designs in the state Department of Ecology's scoping notice would raise the lake level back to where it was before a 1990 flood washed away part of the old dam. Raising the lake back to that level poses questions about how much water the irrigation district is entitled to store and withdraw, along with the obvious question of whether the dam should be designed before that is known.
Under Washington law, a water right can be lost through abandonment or relinquishment. Since 1967 the law has defined relinquishment as non-use for five or more years. Certain exceptions apply. The only one that seems arguably relevant here is for a water supply held in reserve for a drought, but that requires that a dam be kept "in good operating condition." Otherwise, a water right remains valid only to the extent that it is continuously and beneficially used. The purpose of this rule is to ensure that unused water becomes available for other users or instream flow. Those with senior water rights may not sit on those rights.
The irrigation district's claim to Eightmile Lake stems from a 1929 adjudication granting it 2,500 acre feet per year at a withdrawal rate of 25 cubic feet per second. A year later it filed a proof of appropriation. But there were problems from the outset. The dam leaked. It was never built high enough to store 2,500 acre feet. It further deteriorated over the years. The gate valve stopped working decades ago. Since then, the irrigation district has mainly relied on a gravity flow. The Center for Environmental Law & Policy, which has studied this issue, recently concluded: "We are aware of no evidence that IPID [the irrigation district] has ever withdrawn more than 1800 acre-feet, and it may be that no more than 1600 has ever been used."
The irrigation district admits that before 1990 its maximum withdrawal was 1,700 acre feet. Because its dam was further damaged in 1990, it has since only been able to withdraw an estimated 1,400 acre feet per year.
Relinquishment has apparently occurred in two phases – from an original paper right of 2,500 acre feet to a maximum of 1,700 acre feet before 1990, with a further reduction over the past two decades – seemingly leaving the irrigation district with a right to withdraw no more than 1,400 acre feet today. Whether it has used even that much continuously is uncertain.
The two dam designs recently proposed by Ecology would allow the irrigation district to withdraw 2,000 acre feet and more during a drought.
Because the irrigation district plans to transfer to Ecology whatever water right it has over 1,400 acre feet (indeed, if it has any at all), Ecology's Office of the Columbia River says it is conducting some type of tentative determination of the irrigation district's water rights. The law contemplates such a determination when a change of use is filed. Ecology has not estimated when it would complete this process.
It is of course in the public interest that Ecology's determination not be influenced by its own interest in the potential of transferred water rights, but in any case, at this point it is unknown how much its determination will be accepted as binding. Under Washington law, only a superior court can definitively determine the extent of a water right.