Water supply forecasts at major dams in the Columbia River basin dropped again during March, with the forecast at The Dalles Dam dropping from 83 percent of normal in February to 80 percent of normal in March, according to the April 3 water supply forecast by NOAA’s Northwest River Forecast Center.

Snowpack this winter continues to be at an all-time low across several river basins in western Montana, indicating that this year could see water shortages, according to recent projections from the Montana Climate Office.

Spilling instead of passing water through turbines at some Columbia/ Snake River dams to aid safe passage for juvenile salmon and steelhead began March 1, one month earlier than in past years, according to the U.S. Army Corps of Engineers.

The initial phase of reservoir drawdowns on the Klamath River – the draining of Iron Gate, Copco, and JC Boyle reservoirs – is now complete. Draining the reservoirs is a critical step on the path to deconstructing the remaining three Klamath River dams that are slated for removal later this year.

In a study that could help reshape understanding and management of water resources in the Western United States, David Ketchum, a 2023 graduate of the University of Montana systems ecology Ph.D. program, has unveiled a 35-year analysis quantifying the interconnected impacts of climate change and irrigation on surface water flows.

The precision of estimating salmon and steelhead smolt survival rates through Snake and Columbia river dams during the 2023 spring outmigration is remaining elusive. This is the fifth straight year that high levels of court-ordered spill at Columbia and Snake river dams have impacted detection rates of the tagged juveniles as they migrated downstream through eight dams.

Even in the precipitation-heavy Pacific Northwest, more frequent heatwaves are threatening a key source of water supply.

Low water in the upper reaches of the Columbia River -- and concerns about releasing water now from Grand Coulee Dam when it might be needed later for refill and to augment river flows -- has caused fisheries and dam operators of the interagency Technical Management Team to change Columbia River chum salmon operations at Bonneville Dam.

High spill volumes to maximum total dissolved oxygen levels in order to reduce passage of juvenile salmon smolts through turbines at federal Columbia and Snake river dams is likely to be most effective at night, during high river flows and when temperatures are colder, according to a recent study. These are times when juveniles are less active and their swimming ability is low.

The U.S. Army Corps of Engineers will hold four virtual listening-only sessions this month and in October to describe how it will operate the Columbia River system of dams after September 2024 if the Columbia River Treaty negotiations fail to reach an agreement.