Elwha River: Restoration and Recreation
by Amanda Close -- May 21st, 2015
This past weekend I had the opportunity to raft the Elwha River. The Elwha may be familiar to even those that have never spent time on the Olympic Peninsula of Washington state. It is the site of the largest dam removal and second largest restoration project in American history, and the river was featured prominently in the recent documentary “Damnation”. Having spent time discussing the Elwha specifically, and dam removal in general, in several classes this past year, you can imagine my excitement when the owner of the rafting company I worked for last summer invited me to raft it. To back up, no, this is not part of my summer job working for the BLM. Nevertheless it follows the theme of my blog, and since my job has not yet started, I figured this would be a good first post.
Historically the Elwha River was home to the most prolific salmon run on the Olympic Peninsula, and supported all ten of the anadromous salmonid species native to the Pacific Northwest. Unfortunately, the installation of two dams built to generate hydropower in the early twentieth century effectively blocked migrating salmon from the river, save for the 8 miles below the first dam, thus reducing the river’s population to a mere fraction that it once supported. Not only are salmon a major food source for many of the animals that call the Olympic Peninsula home, but also provide valuable nutrient inputs to both the aquatic and terrestrial environments in and around the river. Obviously, the reduction in salmon has resulted in ecological changes within the Elwha River watershed. The sediment trapped behind the 210 foot Glines Canyon dam had also severely reduced the volume reaching the beaches and estuaries at the mouth of the river that were dependent on it.
The meager amount of energy produced by the aging Glines Canyon and Elwha Dams did not justify the environmental impacts just described, and in 2011 the National Park Service began an ongoing project to remove both dams and restore the Elwha to its free flowing state. The Elwha dam was removed by 2012 and the Glines Canyon dam followed by 2014. Today both reservoirs are completely drained and the river has already begun to carve a new meandering path to the sea. The NPS and partners have planted thousands of native riparian species on the newly exposed floodplain in the hopes of speeding up the natural process of succession. What is now exposed silt and sediment will be stabilized by the healthy riparian buffer being planted and will eventually grow into a forest that will shade and provide nutrients to the river.
While the dam removal events themselves can be viewed as catastrophic disturbances that altered an ecosystem that had developed over the past hundred years, the system has proved extremely resilient and is restoring itself faster than many scientists had predicted. Salmon have been spotted in the river and its tributaries upstream of the former dams and the sediment now reaching the sea has nourished an estuary at the mouth and already begun to form a new beach. While it will be many years before the river fully heals, there is a sense of hope in the power of nature to restore balance if given the opportunity.
Visiting the site of the former Glines Canyon dam and rafting through the canyon where the Elwha dam had been was a very cool experience. Probably the most surreal section of river was paddling through the former Lake Aldwell, the reservoir above the Elwha dam. In this hollowed out basin the river has created a new channel for itself amongst stumps of trees that had been underwater for nearly 100 years. The river seems healthy here, sinuous, clear, and cool. If focused entirely on the channel itself it was almost possible to forget we were in a restoration zone. However, looking up at the stark barrenness of the surrounding floodplain and forested upland, a clear demarcation of where the water level once was, put the scene into perspective. I would be very interested to return to this section of the Elwha in five years; I think there would be a profound shift as native vegetation is both planted by the NPS and naturally becomes established.
Training starts on Tuesday for my job with the BLM. I’m excited for that to start, but until it does I’ll continue to raft, hike, and play in the Pacific Northwest!