Williamson River Delta Preserve

Why It's Important
One of the most challenging and pioneering wetland restoration projects in the West is underway at the mouth of the Williamson River on Upper Klamath Lake in southern Oregon. Hosting a multitude of migrating birds, the lake is also one of America's largest freshwater bodies.

Southern Oregon's Klamath Basin, northwest of Klamath Falls

7,440 acres

Plants at the Preserve
Wetland flora includes hard-stem bulrush, Pacific willow, sage pondweed, golden dock and American water plantain.

Animals at the Preserve
Upper Klamath Lake is a world-class haven of biodiversity, hosting 2-3 million birds migrating on the Pacific Flyway, 17 native fish species — eight of which are endemic — and over 15 species of freshwater mollusks found nowhere else on Earth. Declining water quality has endangered two fish species, the Lost River and shortnose suckers.

Why the Conservancy Selected This Site
The Williamson River used to meander across a 12-square-mile delta at the north end of the lake, nourishing vast marshlands, until it was diked and drained for agriculture. While farming still remains, much of the original plant and wildlife habitat is being restored.

What the Conservancy Has Done/Is Doing
With partners including the Upper Klamath Basin Working Group, local industries, Klamath Tribes, Bureau of Reclamation and Natural Resource Conservation Service among others, the Conservancy is restoring wetlands to approximately 7,000 acres and reconnecting the lower six miles of river to its former delta. An additional 750 acres remain in organic alfalfa farming. Levee breaching to restore wetlands for endangered fish and other wildlife and to improve the lake's water quality began in 2003. Learn more about the work here at our Conservation Gateway site.

Ashland Watershed

Protect What You Love

Forests, Rivers, Lakes, Mountains and the Ocean—they're what make Oregon the place we love to call home. 


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