By Ann McCreary

A review of last year’s drought impacts shows a decline in groundwater in eastern Washington, even though stream flows in creeks and rivers have rebounded to more normal levels this spring, according to the Washington Department of Ecology.

The department said it is evaluating impacts of drought on groundwater supplies and will gather more data to better understand declining aquifers and to consider strategies for managing surface and groundwater supplies.

Based on the information assembled to date, there is “reason to be concerned about the sustainability of groundwater levels and storage on the east side” of the Cascade Mountains, particularly in the greater Yakima and Columbia Basins, where substantial on-going declines in groundwater levels and storage have occurred in recent decades, Ecology said.

In an update issued Monday (March 21), Ecology reported snow accumulations are near normal for this time of year, and forecasts for the April-September runoffs are within the normal range as well.

Last year at this time was a very different story. The drought of 2015 was called the “snowpack drought” due to record low snowpack.

Washington State had normal or near-normal precipitation during the 2014-2015 winter. However, during October through March the average statewide temperature was 40.5 degrees – 4.7 degrees above the 20th century long-term average and the warmest October-March period on record, according to Ecology.

Washington experienced record low snowpack because mountain precipitation that normally fell as snow instead fell as rain.

The snowpack deficit was compounded as precipitation began to lag behind normal levels in early spring and into the summer.

With record warm spring and summer temperatures, and little to no precipitation over many parts of the state, rivers and streams experienced record low flows, and drought conditions caused extensive damage to crops and aquatic species.