Demanding Responsible Decisions from Snohomish PUD

Skykomish River Sunset Falls Hydropower Project Facts Check - Page 1

  • 1. construction & operating costs
  • 2. exploratory costs
  • flow data
  • runoff patterns
1. Factual data showing that the increase in fall and winter floods is likely to hurt power production.

The Sunset Falls hydroelectric facility would be forced to shut down when flows reached 8,000 cfs (cubic feet per second) or higher on the South Fork of the Skykomish (well below flood level).

Source: January 28, 2016 Sunset Fish Passage and Energy Project Draft License Application – DLA_V1, Section 3.2.2.

"Total River Flow" does not mean "Usable River Flow".

Snohomish PUD has been focusing on total monthly river flows because they are expected to increase during the fall and winter due to climate change (more rainfall, less snow). However, experts expect these higher flows to often take the form of flooding events, which would hinder plant production. (Its shutdown point of 8,000 cfs is well below flood level.)  See below.

Flooding events are expected to become far more common.

This peak flow chart below for the Skykomish River shows that "the three largest events have all taken place since about 1980, and that the largest (and most recent) event is about 30% higher than the largest previous event."

Source:  March 14, 2012 “Impacts of Climate Variability and Climate Change on Transportation Systems and Infrastructure in the Pacific Northwest” by Alan F. Hamlet. Link to document.

There is a large amount of research indicating that fall and winter storms will be both more frequent and more intense.

Source:  November 2015 “State of Knowledge: Climate Change in Puget Sound” Section 3, by Climate Impacts Group, University of Washington.  Link to full reportSection 3.

Rivers are expected to flood more severely.

Peak river flows for 12 Puget Sound watersheds are expected to increase by 18% to 55% on average.

Source:  November 2015 “State of Knowledge: Climate Change in Puget Sound” Section 3, by Climate Impacts Group, University of Washington.  Link to full reportSection 3.

Just a heads up: Don't miss the "Questions for Snohomish Public Utility District" at the bottom of this page.

"100-year floods" are expected to become "30-year floods" on the Snohomish River by 2040.

(The Skykomish River flows into the Snohomish River.)

Source: April 2016 “Adapting to Change: Climate Impacts and Innovation in Puget Sound” by University of Washington Climate Impacts Group and The Nature Conservancy. Link to document.

Is Snohomish Public Utility District disregarding its own Climate Change Policy?

SnoPUD has a publicly stated goal of environmental responsibility and financial stability in regards to addressing the issue of climate change.

Source:, Climate Change Policy page.  Link is here.

However, Snohomish PUD's 2015 credit rating by Moody's noted that their rating could go down if it expands too aggressively into owned generation that is too risky.  A hydropower project on a river that supports threatened fish species, near an active landslide, scheduled to operate during a 50-year period of significant climate change might fit that description.

Source:  June 8, 2015 Moody’s Investors Service rating anlysis of Snohomish PUD. ELGS 2015 Moodys.


Please click the button below to see how you can quickly and easily submit a short form asking the Snohomish PUD Commissioners to abandon the Sunset Falls Hydropower project immediately.


1. There is an enormous amount of scientific data that predicts increasingly frequent and severe flooding during the fall and winter on rivers like the Skykomish in the future. Why do SnoPUD staff continue to focus on how this would increase Total Flow rather than how it is likely to decrease Usable Flow?

2. How was it environmentally or financially responsible (as per your Climate Change Policy) to use river flow data starting from 1928 for the important research that is necessary in order to not base the Sunset Falls project on overly optimistic revenue estimates?

3. According to Moody's 2015 analysis, expanding aggressively into owned generation without conservative risk mitigation could harm Snohomish PUD's credit rating. Does Snohomish PUD consider the 50-year Sunset Falls hydropower project a conservative risk?  If so, on what basis?