Phillips Reservoir reached a milestone early on Wednesday, April 30.

The reservoir on the Powder River in Sumpter Valley, about 17 miles southwest of Baker City, is holding more water than at any time in almost eight years.

As of 4:30 a.m. on Wednesday, the reservoir was holding 53,654 acre-feet of water. That’s the most water in the reservoir since late July of 2017.

Phillips peaked at 53,587 acre-feet on June 15, 2023. A year ago, on May 16, 2024, the reservoir reached a maximum volume of 53,401 acre-feet.

(One-acre foot of water would cover one acre of flat ground to a depth of one foot. It also equals about 326,000 gallons.)

Despite the milestone, Phillips is well below full, which is 73,000 acre-feet (the reservoir can hold more water if needed for flood control). It hasn’t been full since June 2017.

The reservoir was created by the construction of Mason Dam, finished in 1968. It was built for flood control and to store water to irrigate more than 30,000 acres, mostly in Baker Valley.

Since 2017, a series of drought years has left the reservoir less than half full most of the time.

A heavy snowpack during the winter of 2023, and a rapid snowmelt that spring, boosted the reservoir to its highest level since 2017.

The next winter’s snowpack wasn’t as deep, but the reservoir wasn’t depleted as much as during the drought years, and it reached nearly the same volume in the spring of 2024.

This winter’s snowpack was similar to 2023’s. But the snow has melted relatively slowly, and with little rain falling since mid March, the Baker Valley Irrigation District has had to start releasing more water from the reservoir, which slows the refilling rate.

The release rate on Wednesday morning was 144 cubic feet per second (cfs). The Powder River, the main source of water for the reservoir, was running at 264 cfs at Hudspeth Lane, just west of the reservoir, on Wednesday morning. Another main tributary, Deer Creek on the north side of the reservoir, was measured at 147 cfs.