Roza Water Users-

• Roza is targeting Monday October 12 to end diversions. The lower half of the district will have water for a day or two after that due to the travel time for the water.

• You will see water in the Main Canal for about 3 weeks in a 22 mile stretch more or less from Maple Grove Rd to Missimer Rd.  We are feeding the Aquifer Storage and Recovery (ASR) pilot project with a few hundred acre feet of water from the Wasteway 5 Re-Regulation reservoir in order to store water in the Wanapum aquifer via a well that is 1,165 ft deep. The water you see in the canal after we shutdown is not available for irrigation.

The water is highly filtered and UV treated and is being injected under a permit from the Dept. of Ecology. After a 30 day rest period the water will be pumped out for about 30 days to determine the potential yields. The concept looks promising and may be scalable. The pilot test is being funded primarily with state and federal grants with a local match. We will send out more detail on the project later this year..

• The recent storms have been a very positive development for October water supply and carryover storage going into the 2027 water year.

• USBR’s water supply forecast increased from 58% to 60% on September 8^th. The supply forecast increased again on September 14^th to 62%, which is much better than the March forecast of 44%.

• A one page table is attached which lists out the monthly water forecasts in recent drought years for comparison. You can see how each drought is a bit different in how things unfold over the winter/spring and during the season.

2026 is a good example of a cooler/wetter June helping to reduce irrigation demand. Not having an extended stretch of 100+ degree heat this summer also helped.

• We learned this week that we had an email glitch with the Sept. 18^th update email and not everyone received it.

Scott Revell, District Manager ~ (509) 840-2721 cell