Tuesday, Nov.13, 7 pm.
Please bring a friend and join us for the next Olympia Science Café.
When: 7:00 pm, Tuesday, November 13, 2012
Where: Room 110, Harned Hall, Saint Martin’s University, 5300 Pacific Avenue SE, Lacey, Washington
- Please note that a class is in session in Room 110 until 6:50 p.m., so we ask that you remain in the lobby until the class is dismissed.
- There is no charge to park on campus after 5:00 p.m. We suggest parking lots M and N for proximity to Harned Hall. (See attached map.)
- Driving directions and campus map:http://www.stmartin.edu/about/DrivingHere.aspx#Saint_Martins_Universitys_address http://www.stmartin.edu/about/SMUCampusMap.pdf
November’s topic is Elwha River Dam Removal: Past, Present, and Future.
The removal of the Elwha River dams on the Olympic Peninsula of Washington State is a unique opportunity to examine ecosystem recovery on a watershed scale and has spurred collaborative research efforts among diverse groups. For the past century, the two dams blocked the upstream movement of anadromous fish to over 90% of the watershed and restricted the downstream movement of sediment, wood, and other organic materials to the lower river and estuary. Populations of all five Pacific salmon species and steelhead in the Elwha are critically low, habitat complexity decreased in the middle and lower river, and downstream coastal habitats are sediment starved.
Simultaneous deconstruction of the two dams began in September 2011 and is expected to take 2-3 years to complete. During and after that time, researchers are examining dam removal effects in three geographic regions: the former reservoirs, across the river floodplain, and in the nearshore environment. Short-term (< 3 years post dam removal) monitoring is focused on the downstream transport of approximately eight million cubic meters of fine sediments accumulated in the reservoir deltas, associated peaks in river and estuary turbidity levels, and re-vegetation of the reservoir themselves. Longer-term effects of dam removal (> 5 years) to be evaluated are the delivery of gravels and cobbles to the lower river and nearshore, the re-establishment of a natural wood delivery regime, the re-colonization of the upper watershed by anadromous fish, and the associated effects on aquatic and riparian foodwebs.
Sarah Morley, Research Ecologist at the Northwest Fisheries Science Center (Watershed Program, Fish Ecology Division) will present an overview of the Elwha restoration project, and highlight changes observed in this first year of dam removal.