Dungeness River Watershed

Know Your Watershed

The Dungeness River Watershed is a unique area of the northeast Olympic Peninsula with distinct features that define it as our home. We believe all residents of the watershed should be filled with a sense of pride, ownership, and a feeling of stewardship for this lovely area. Unfortunately many problems caused by human activities, like degraded water quality, water shortages, and loss of wildlife habitat, threaten the Dungeness River and its associated watershed. These pages give you a quick look into this astonishing area’s history, habitats, plants, animals, people, and problems.

Rain Shadow Effect

This “rain shadow effect” is a dominant feature of the climate of the northeast corner of the Olympic Peninsula, extending across to the San Juan Islands and Whidbey Island. Large Pacific weather systems usually move onshore from the west-southwest, dropping large volumes of rain and snow as they rise and cool over the Olympics. They then warm up and lose moisture as they reach the other side (called the lee side) of the mountains. This makes the Sequim area much drier, allowing different plant communities and species to occur here.

Rain Shadow Effect infographic

 

Mount Olympus and Sequim are only 35 miles apart, but Mount Olympus typically gets over 200 inches of rain and snow each year.

Sequim receives less than 20 inches of precipitation a year, making it the driest area of western Washington. The average yearly precipitation for local sites clearly shows these differences:

  • 16.3” – Sequim
  • 25.3” – Port Angeles
  • 28.7” – East Orcas Island (San Juans)
  • 37.2″ – Seattle
  • 54.2” – Quilcene (northern Hood Canal)
  • 55.8” – Elwha Ranger Station
  • 79.5” – Aberdeen (Grays Harbor)
  • 94.5” – Cushman Dam (above Hoodsport)
  • 108” – Forks

Weather Patterns

Learn more about local weather patterns at the Olympic Rain Shadow website:

Taking Care of the Dungeness River

Our river is central to the culture and life of our area, please take time to read the following and learn what is being done to to care for it and how you can help!