Martin said compared to data collected in August in the past 50 years, flows at the mouth of the Sprague River are lower than normal.

The Klamath Tribes called on its “time immemorial” water right to increase flows in the six waterways on May 13.

OWRD adjudication regulation provides surface water rights based on priority date of property claims, and was first implemented in the Klamath Basin in 2013. Adjudication is based on “first in time, first in right,” meaning the older the claim date, the more senior the water right.

According to Martin, Trout, Whisky and Larkin creeks were regulated to time immemorial rights. The other streams have been regulated to 1905, meaning streamside landowners with water rights more recent than 1905 are experiencing water restrictions.

“The date looked like a good one to get the water we needed,” Martin said.

Martin said Wood River was briefly regulated, but flows came up and the regulation was lifted.

The agricultural Bonanza ADR wells were regulated July 14. The shutoff is based on groundwater levels, not on a water call, according to Martin. He said the wells — owned by 13 landowners — are regulated if groundwater levels are a half a foot lower than the elevation of Lost River.

“They impact the flow of Bonanza Big Springs, which contributes to Lost River when flowing,” Martin said.

According to Martin, the Tribes’ water call mostly affects surface water rights. Only wells located along Whisky Creek and Lower Sprague River were regulated after the Tribes’ water call was validated, he said.

Martin said regulations will be lifted based on natural stream flow and water use.

“We have to see what both of those trends are doing before we can make decisions about lifting regulation,” he said.