• Olympic: Three Parks in One

    Olympic

    National Park Washington

There are park alerts in effect.
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  • Olympic Hot Springs Road Closed

    The Elwha Valley's Olympic Hot Springs Road is closed to public entry beyond the Altair Campground. Olympic Hot Springs is not accessible from the Elwha. The road is expected to re-open by Summer 2015.

  • Safety Advisory: Mountain Goats

    NPS has received reports of aggressive mountain goats near trails at Hurricane Ridge, Royal Basin, Seven Lakes Basin, Lake of the Angeles, & Grand Pass. Visitors are required to maintain a distance of at least 50 yards from all wildlife. More »

The Elwha Watershed

The Elwha Watershed:
With 321 square miles of drainage and 70 miles of river and tributaries, the Elwha River is the largest watershed in the peninsula. A large amount, 83%, is located within Olympic National Park, sheltering it and making it a particularly pristine river habitat.

The Elwha dam is located at river mile 4.9, behind which is Lake Aldwell. Glines Canyon dam is downstream at river mile 17, holding back Lake Mills. The Lower Elwha Klallam tribe reservation is located around the mouth of the river on the Strait of Juan de Fuca. Just east of this sits the city of Port Angeles.

 
Map of Elwha watershed and dams
Map of the Elwha watershed and its surroundings

Did You Know?

Mossy trees in the Hoh Rainforest

...that one criterion for the determination of a temperate rain forest is that the amount of moss and other epiphytes exceeds the weight of all the foliage (leaves and needles) per acre by at least two times.