Statutory Goal: An ecosystem that is supported by groundwater levels as well as river and streamflow levels sufficient to sustain people, fish, and wildlife, and the natural functions of the environment

Summer Streamflows
Summer low flows

The only indicator of the Abundant Water goal fell short of meeting its recovery target

The summer low flow indicator, the only indicator for the Abundant Water goal, did not meet its 2020 target because several rivers (all those without dams or enclosures) had lower than expected flow trends.

  • The summer low flow indicator measures the long-term trend of annual summer low flows for each of 12 rivers. Generally, the target calls for stable or increasing summer low flows.
  • Summer low flows in most rivers without dams have declined since the 1970s. Regulated rivers, those with dams, have had stable or even increasing flows. This is an expected result, since licensed dams must release agreed-upon instream flows. Therefore, progress of the summer low flows indicator is mixed.
  • The Dungeness and Puyallup, two of the unregulated rivers, are meeting the recovery target for stable flows. Water from melting glaciers feeds those rivers.
  • Summer low flows in the Puget Sound basin are affected by a variety of human activities, including land-use conversion, forest practices, and human water use, as well as by natural factors such as rainfall. The summer low flow indicator signals the combined effects of human and natural factors, with the potential for climate to mask the effects of human activities.

For more details about ecosystem conditions relating to this goal, please see our Story Map on Puget Sound Info.

Climate change threatens sufficient water quantity

Climate change poses a high risk to the Abundant Water goal (Siemann and Binder 2017).

  • decreased snowpack; and
  • increased evaporation and vegetative demand for water.
  • Accelerated glacial melt may temporarily offset diminishing low flows in some rivers (Mauger and Vogel 2020).

Signals from the 2020 State of Our Watersheds Report

Groundwater Withdrawals Impact Surface Flows: Since 1980, over 67,000 wells have been developed in the Puget Sound Region. Of these, 5,815 were built between 2015-2019, a 40% increase over the number of wells built during the previous five years (2010-2014). This increasing rate of new well installations threatens groundwater availability, which has effects on instream flows and overall ecosystem health across the region.