Detroit Lake reaches 'full pool,' promising good recreation season
Story updated at noon on May 11
This summer should be a good one at Detroit Lake.
A wet and snowy April brought a surge of water that should allowed the reservoir east of Salem to reach "full pool" this week and well before the important Memorial Day weekend.
Detroit Lake's water level reached 1,555.5 feet above sea level, what's considered its high water mark for the season, on Tuesday.
A boost to tourism season
Officials with the U.S. Army Corps of Engineers were confident that Oregon's best snowpack since 2011 would keep the reservoir at a good level into late summer — allowing for recreation and boat storage throughout peak tourist season.
Snowpack in the Willamette Basin sits at 179% of normal.
“Most if not all of the boat ramps should be accessible by Memorial Day weekend and through Labor Day as well,” Salina Hart, water master for the Corps, said.
Detroit mayor Jim Trett said a full lake is critical as the area continues to rebound from the Labor Day fires of 2020 that burned much of the town. He said three to four food carts will return this summer and the town is planning concerts at the park.
"It's great news because a full lake is key not only to our economy, but for the Santiam Canyon," Trett said. "When we have lots of people up there in the summer, it feels normal, like before the fires, and it encourages those businesses to return and start building."
Late season rally
Just a month ago, Detroit Lake looked to be in bad shape and in danger of a low-water year. February and March both saw below-average precipitation.
Then April arrived with rain, wind and snow — leading to Oregon's biggest snowpack since 2008.
“The extremely wet April helped quite a bit,” Hart said. “Snowpack in the North Santiam continued to build and peaked in late April much larger and later than normal.”
Historically, Detroit Lake is filled almost entirely by spring rainfall, with snowmelt accounting for 10% of the reservoir’s refill. But this year’s snowfall was so large it played a bigger role, especially as it melted this past weekend during a run of temperatures in the 70s and 80s.
Even after last weekend’s melt, Oregon’s Central Cascades still have plenty of snow — 184% of normal at this point.
“Given the late season melt, reservoirs that do have heavier snow influence like Detroit will see more additional refill benefit too,” Hart said.
Detroit Lake stores less water
Detroit Lake is managed primarily to reduce the threat of floods.
Its level is managed to follow a "rule curve" that keeps it very low in winter, so it can reduce the threat of floods in the Willamette Valley by absorbing large rainfall events. Then, it is gradually refilled during the spring to store water for fish, irrigation and recreation.
Detroit still is storing less water than previous years.
Until 2021, the Corps’ summertime “full pool” level was 1,563.5 feet above sea level. That was dropped to the current level, 1,558.5 feet, amid concerns about a Cascadia earthquake.
Five feet less water is enough to reduce stress on the lake’s dam spillway gates and reduce the chances of the dam breaching by 10%, the Corps said at the time of its decision.
However, the lower water level does leave some places drier than in previous years, including the Detroit Flats area, which frustrates some local residents.
That decision — and new summertime high water levels — is unlikely to change anytime soon, officials said.
"Unless funding can be made available, it’s not likely going to change," Corps spokeswoman Kerry Solan said.
Zach Urness has been an outdoors reporter in Oregon for 15 years and is host of the Explore Oregon Podcast. Urness is the author of “Best Hikes with Kids: Oregon” and “Hiking Southern Oregon.” He can be reached at zurness@StatesmanJournal.com or 503-399-6801. Find him on Twitter at @ZachsORoutdoors.
This article originally appeared on Salem Statesman Journal: Detroit Lake reaches 'full pool,' promising good recreation season
