Water Resources Engineering (WRE) connects engineering hydrology and hydraulics with societal, environmental, and other issues. Our student Mr. Austin makes this connection here…

National Geographic News reported “Bulldozers Tear Into Big Washington Dams” online on September 23, 2011. This article was about the removal of two large dams on the Elwha River in Olympic National Park, and the restoration of the river ecosystem.  This is important because it is the largest dam removal to take place in the US and it will allow salmon to spawn in 65 miles of river for the first time in almost 100 years.  This article seems to be accurate, the facts match those from other news sources about the story.  There have been many scientific studies on the Elwha River to monitor the impacts that removal of large dams might have, and document the system’s progress back to what it was formerly.

Rivers and their interconnected resources illustration. Image courtesy of web.

This news story relates to societal, economic, and global context.  Societal issues affect people and communities; this dam removal especially affects the Lower Elwha Kallam Tribe who have been advocating for its removal so they can again fish for salmon in the river.  Economic context pertains to money; the Elwha River will now be open for rafting and kayaking and the pacific northwest salmon fishery will be improved, possibly increasing the population by over 25,000 fish. Global impact affects places around the world, since this is such a large and well studied dam removal, it may form the basis of removal for other dams in the future and around the world. Environmental relates to sustainability and negative impact on ecosystems. The river ecosystem will improve with increased nutrients from salmon swimming upriver and sediment flowing down to build the estuary.  When the dams are fully removed, the salmon will swim upstream, spawn, and maybe get eaten by a bear (see photo below).  The bear will then poop in the woods where the nutrients will supply a cedar tree, which will grow larger.  The presence of salmon in the river will positively affect over 130 species, either directly (the bear) or indirectly (the cedar).  See time elapse webcam photos of the removal of the 210 foot Glines Canyon Dam on the Elwha River.

Advertisements