Elwha Watershed Information Resource

Mouth of the Elwha River at the Strait of Juan de Fuca. Don Pruett, National Park Service

Currently, the Elwha River contains low concentrations of dissolved and suspended sediments, nutrients, and organics due to the trapping of sediments and wood behind the dams, and the blockage of anadromous fish to reaches above the dams. As salmon recolonize the middle and upper Elwha River after dam removal, marine-derived nutrients from their spawned-out carcasses will help stimulate algal production, increasing food availability for invertebrates and for the juvenile fish that feed upon them. Ultimately, increased productivity above the former dams will help in improving adult fish returns. Below the dams, a return to normal sediment and wood transport will increase floodplain complexity and thus improve habitat for algae, invertebrates, fish, wildlife, riparian plants, and other floodplain organisms. It is important to understand the current state of the Elwha aquatic ecosystem (before the dams are removed) in order to gauge the effectiveness of restoration efforts (post dam removal). For example:

• Monitoring water quality (pre dam removal) will allow scientists to compare future water quality levels during the phases of dam removal.
• Developing an inventory of algae and invertebrates (pre dam removal) will provide a baseline of existing organisms that can be compared later to post dam removal inventories.

Researchers have developed three primary studies to gather baseline information before dam removal. These efforts are discussed in the sections below.

Consequences of the Elwha River dam removals on nearshore habitats and ecosystems

Primary and secondary producers in the Elwha River: establishing baseline conditions

Documenting current stream productivity and fish populations prior to dam removal in the Elwha River: Setting the stage for long-term monitoring of ecosystem responses

Consequences of the Elwha River dam removals on nearshore habitats and ecosystems

Study Overview: In 2006, the United States Geological Survey (USGS) began implementing a new interdisciplinary research project in the Elwha River and nearshore. One of three projects supported under the Coastal Habitats in Puget Sound (CHIPS) initiative, this project integrates researchers from the USGS water, biology, geography, and mapping divisions.

The project objective is to link studies of physical, chemical, and biological processes in the lower river, estuary, and nearshore. The investigation reflects the temporal context of the Elwha River restoration project by dividing activities into three periods (before the dams are removed, during the dam removal process, and the recovery period following dam removal). This project is linked to existing USGS work, as well as that of other entities.

Project data will be used to:

• Establish baseline characterizations of habitats in the Elwha river estuary;
• Define how the transport of sediment and nutrients affects these habitats; and
• Understand how key species currently use these habitats.

Research Activities: The field research activities from the first year (2006) included:

• Surveying (bathymetric and topographic) in the lower river.
• Profiling the current (velocity and direction) of the river mouth over a tidal cycle during May high flows.
• Studying river metabolism in June and August.
• Taking monthly nutrient samples at 5 different locations to determine the nutrient status of the lower river and estuary.
• Collecting juvenile Chinook (Oncorhynchus tshawytscha) salmon from different habitats in the lower river/estuary for otolith analysis.

Collaborators:

• Matt Beirne, Lower Elwha Klallam Tribe
• Jeff Duda, United States Geological Survey
• Kurt Fresh, NOAA Northwest Fisheries Science Center
• Guy Gelfenbaum, United States Geological Survey
• Chris Konrad, United States Geological Survey
• Mike McHenry, Lower Elwha Klallam Tribe
• Reg Reisenbichler, United States Geological Survey
• Larry Ward, Lower Elwha Klallam Tribe
• Jonathan Warrick, United States Geological Survey
• Brian Winter, National Park Service

Primary and secondary producers in the Elwha River: establishing baseline conditions

Study Overview: This project focuses on gathering baseline information on the primary producers (for example, algae) and secondary producers (for example, invertebrates) that directly affect aquatic productivity. The project was initiated in 2003 and will continue for 3-4 years post dam removal, pending funding.

Primary and secondary producers are the foundation of the aquatic food web upon which fish and other organisms depend. As such, it is critical to understand how these producers have potentially been altered as a result of the Elwha dams before the dams are removed. Without that understanding, it will be very difficult to predict or interpret changes that may result from dam removal. Towards that goal, researchers have been collaborating to:

• Build on previous data collection efforts;
• Coordinate and standardize sampling protocols; and
• Determine appropriate scales and intensity of sampling.

Research Activities: Researchers from NOAA and USGS are obtaining baseline data on densities, composition, and diversity of periphyton and benthic invertebrate assemblages. Samples are being collected from approximately 50 sites distributed across the three reaches of the Elwha River, and 12 sites from a reference reach on the Quinault River. Additionally, data is being collected from each site on physical habitat (substrate, canopy, flow, and gradient) and water chemistry (nutrient concentrations, conductivity, and temperature).

Bill Eaton from Peninsula College is leading a team of Research Experiences for undergraduate students from Peninsula College and Western Washington University. This team is working to describe functional and genetic diversity of microbial communities in periphyton and soil samples collected along the Elwha River. This research was initiated in 2006 and will continue post dam removal for at least three years, pending funding.

Future research projects (if funding is available) include:

• Measurement of benthic respiration;
• Seston sampling,
• Additional microbial sampling,
• Carcass addition experiment (currently funded); and
• Expansion of reference reach sampling.

Project Leads:

• NOAA Northwest Fisheries Science Center: Sarah Morley and Holly Coe
• USGS Western Fisheries Research Division: Jeff Duda

Collaborators:

• Tim Beechie, NOAA Northwest Fisheries Science Center
• Bill Eaton, Peninsula College
• Kris Kloehn, NOAA Northwest Fisheries Science Center
• Martin Lierrmann, NOAA Northwest Fisheries Science Center
• Mike McHenry, Lower Elwha Klallam Tribe
• George Pess, NOAA Northwest Fisheries Science Center
• Sonny Simpson, Lower Elwha Klallam Tribe

Documenting current stream productivity and fish populations prior to dam removal in the Elwha River: Setting the stage for long-term monitoring of ecosystem responses

Study Overview: This project focuses on stream productivity and fish populations--specifically, looking at marine-derived nutrients from salmon carcasses.

The United States Geological Survey (USGS) is working closely with the National Park Service, the Lower Elwha Klallam Tribe, and NOAA Fisheries to:

• Establish and test protocols for fish population assessment;
• Determine baseline status of primary and secondary aquatic communities in multiple habitats; and
• Establish long-term monitoring stations of low-concentration water chemistry and stable isotopes (which will be affected by decomposition of salmon carcasses as these populations recover).

The dam removals, in concert with natural recolonization and proposed hatchery supplementation, will restore the vital role of anadromous salmonids in this ecosystem. Beginning to monitor ecosystem effects, such as marine-derived nutrients, prior to dam removal is extremely important. Data collected during these initial monitoring efforts will help the National Park Service establish baseline data. With baseline data, researchers can compare ecosystem responses before and after the dam removals.

Research Activities: From 2004-2007, researchers established 56 study sites in locations in the Elwha River (above, between, and below the dams) and in the upper Quinault River. At these sites, researchers:

• Collected habitat information;
• Sampled periphyton and macroinvertebrate communities (standing biomass as well as community composition); and
• Analyzed water chemistry (dissolved and total macronutrients).

At a floodplain scale, where the 56 sites were embedded, tissues were collected (from algae, macroinvertebrates, fish, and vegetation) and analyzed for stable isotope levels. DNA was collected from fish throughout the Elwha River basin to establish genetic baselines using microsatellites (Gary Winans, NOAA Fisheries). DNA samples were also taken to determine whether introgression has occurred between rainbow trout (Oncorhynchus mykiss) and introduced cutthroat trout (O. clarki) or between the Endangered Species Act-listed bull trout (Salvelinus confluentus) and the introduced brook trout (S. fontinalis). Analyses are ongoing and will be presented in peer reviewed publications.

Collaborators:

• Sam Brenkman, Olympic National Park
• Holly Coe, NOAA Northwest Fisheries Science Center
• Pat Connolly, United States Geological Survey
• Jeff Duda, United States Geological Survey
• Jerry Freilich, Olympic National Park
• Mike McHenry, Lower Elwha Klallam Tribe
• Sarah Morley, NOAA Northwest Fisheries Science Center
• Carl Osterberg, United States Geological Survey
• George Pess, NOAA Northwest Fisheries Science Center
• Gary Winans, NOAA Northwest Fisheries Science Center

Reference

NPS (National Park Service). 1996. Elwha River Ecosystem Restoration, Draft Environmental Impact Statement. National Park Service, Olympic National Park, 600 East Park Avenue, Port Angeles, Washington, 98362.

Additional Information

Moulton, S. R., J. G. and others. 2002. Revised protocols for sampling algal, invertebrate, and fish communities as part of the National Water-Quality Assessment Program. USGS Open-File Report 02-150, Department of the Interior.

Munn, M. D., and others. 1999. An assessment of stream habitat and nutrients in the Elwha River basin: Implications for restoration. U.S. Geological Survey Water-Resources Investigations Report 98-4223, Tacoma, WA.

Munn, M. D., M. L. McHenry, and V. Sampson. 1996. Benthic macroinvertebrate communities in the Elwha River Basin, 1994-1995. U.S. Geological Survey Open-File Report 96-588, Tacoma, WA.

Winter, B. D., R. Reisenbichler, and E. Schreiner. 2000. The importance of marine-derived nutrients for ecosystem health and productive fisheries. Olympic National Park, National Park Service, U.S. Department of the Interior.