The HFF research and restoration program contributes enormously to efforts aimed at improving trout habitat. More than 100 research projects to date have provided a scientific basis for management and decision-making in the Henry's Fork watershed. The Foundation works cooperatively with federal and state agencies, academia, and nonprofit organizations to develop, fund, and complete projects.
To view recently completed restoration projects click here.
Gill Lice Study
The Idaho Department of Fish and Game and the Henry’s Fork Foundation have launched a study investigating gill lice in the Upper Snake River region after receiving reports of anglers observing gill lice in rainbow trout in the Henry’s Fork. We need your help to gather information on the presence and absence of gill lice.
Help by gathering information and sharing it with us!
The Caldera Project: Restoring Wild Trout Fisheries
The Caldera, named for the 28-mile section of river from Island Park Dam to Mesa Falls, includes the Ranch, Box Canyon, and many other popular stretches. Through the Caldera Project, HFF coordinates a team of scientific experts to build on existing research in understanding the unique aquatic habitat of the Caldera.
The Caldera Project also identifies restoration projects to improve the legendary Caldera fisheries. The Caldera Project includes the following projects:
Habitat-Use Study: What Fish Want
In the spring of 2013, HFF and partnering agencies embarked on a 3-year study to find the ultimate link between the trout population and fishing experience in the famed Harriman State Park section of the Henry’s Fork. The study will assess the habitat preferred by adult rainbow trout in the Harriman State Park reach throughout the fishing season, with a long-term goal of improving adult trout habitat in the Harriman reach. Read our blog or download the summer 2013 issue of The Voice of the River to learn details of the study.
Grand Valley State University biology professor Dr. Eric Snyder will direct the study with graduate student Zachary Kuzniar conducting field work on the ground. HFF staff and interns will provide field work support.
In spring 2013, we radio-tagged 40 adult rainbow trout. This video shows how researchers perform surgery on fish to insert radio-tags.
Thurmon Creek Study: The Value of Small Tributaries
The 9-mile Ranch section of the Henry's Fork through Harriman State Park is legendary in the world of American fly-fishing. The reputation and popularity of the Ranch have made it the focus of research for over 30 years. Dozens of completed studies have created a wealth of knowledge about the fishery and significant efforts to improve it. The Ranch is the product of a complex set of natural and man-made influences, and the quality of angling has varied over the years.
Since 2008, the Foundation has examined how small tributaries like Thurmon Creek in Harriman State Park contribute to the survival of trout in their first winter of life. Through the use of PIT (Passive Integrated Transponder) tags, HFF marks each trout migrating into Thurmon Creek with a unique code that provides insight on survival, winter growth rates, and most importantly, when the trout use habitat in the creek.
An automated PIT-tag detection system was operated over the winter of 2012-2013 to record the migration of fish out of Thurmon Creek and back into the Henry’s Fork. These migration data will be used to quantify the number of young fish that successfully winter in Thurmon Creek and determine future habitat and/or fish passage improvements that will enhance the contribution of Thurmon Creek to the Henry’s Fork population.
Project partners and contributors: Harriman State Park, Cross Charitable Foundation, Fall River Electric Co-op, Idaho Department of Fish and Game, Parts Service, Kast Gear, Snake River Prototype, and individual donors who provided matching funds.
Buffalo Fish Ladder: Monitoring the Contribution to Fisheries
As of summer 2013, over 30,000 rainbow trout have migrated upstream through a fish ladder at the Buffalo River Hydroelectric Project. A large number of brook trout, whitefish, and non-game fish species have also used the ladder. There has been a generally increasing trend in use of the fish ladder since it was installed, and the next phase of monitoring will allow us to quantify the contribution of the Buffalo River to the wild trout population in the Henry’s Fork.
The hydroelectric project was relicensed in 2004 and several fish passage improvements were made at the facility in 2005:
Upstream-migrating fish benefit from a state-of-the-art, 270-foot-long fish ladder that was designed to allow young rainbow trout to pass over the twelve-foot-high dam. HFF monitors fish moving upstream and downstream through the project.
The turbine intake was screened with a smaller opening, and the upstream face of the dam was resurfaced. These changes should prevent fish migrating downstream at the dam from being injured or killed when entering the turbines, or being trapped in holes in the dam.
These fish passage improvements were made to allow juvenile rainbow trout from the Henry’s Fork to access crucial winter habitat. Offspring from spawning rainbow trout in the Buffalo River and juvenile trout migrating from the Henry's Fork are able to spend their first winter in the Buffalo River watershed upstream of the dam. After their first winter, these juvenile trout move to the Henry’s Fork where they can grow and contribute to the fishery from Box Canyon through Harriman State Park.
Project partners and contributors: Caribou-Targhee National Forest, Idaho Department of Fish and Game, and Fall River Rural Electric Cooperative (hydroelectric project owner).
- Caldera Project Brochure (PDF)
- Caldera Project Assessment (PDF)
- Aquatic Macrophytes at the Henry's Fork River in 2009 (PDF)
- Water Quality Assessment of the Caldera Reach 2009 (PDF)
- Hydrology, Geomorphology, and Sediment Transport in the Caldera Reach (PDF)
- Caldera Symposium Abstracts and Video
In 1996, HFF began the Habitat Assessment Project, which collected information on aquatic and riparian habitat conditions, fish populations, and aquatic invertebrates on every reach of the Henry’s Fork and most of its tributaries. That project required five years to complete and provided a set of information that could serve as a baseline to compare with future conditions.
In 2000, a set of nine “indicator” sites were selected for long-term monitoring. Six of these are located on the main stem of Henry’s Fork from Mack’s Inn to Rexburg, and one each on three tributaries: Henry’s Lake Outlet, Sheridan Creek, and Fall River. These sites were monitored each year from 2001 through 2005, adding to the data collected during the 1990s. Download the long-term monitoring report from 2005.
The next round of monitoring is under way, providing a 20-year comparison with data collected during the initial habitat assessment and a 10-year comparison with conditions in 2005. The latest project is the Henry’s Fork water-quality monitoring.
Ecological processes and physical properties of water critical to growth and survival of wild trout are being studied as part of the latest monitoring project. The placement of study sites allows us to identify how water quality changes along the course of the Henry’s Fork as reservoirs, irrigation withdrawal and return-flow points, tributaries, and natural ecological boundaries affect physical, chemical, and biological processes. This knowledge will help river managers to optimize not only water quantity but water quality as well.
After a successful first year of installing and monitoring four stations along the Henry’s Fork upstream of Ashton Reservoir, HFF expanded its water-quality monitoring network into the lower watershed during the summer of 2015. HFF installed automated instruments (called “sondes”) near Ora Bridge, St. Anthony, and Salem-Parker highway, complementing those installed in 2014 at the Flatrock Club, Island Park Dam, Pinehaven, and Marysville.
The HFF sondes record temperature, dissolved oxygen, depth, dissolved solids, turbidity, chlorophyll, and blue-green algae at 15-minute intervals. At each sonde site, staff regularly collects water samples, which are analyzed for phosphorus and suspended sediment concentrations.
The results from field sampling will be used to develop statistical relationships between constituents that cannot be measured by the sondes and those that can, so that in the future, the sonde data can be used to infer information about a wide range of water-quality parameters.
During 2015, HFF collaborated with several agencies to focus intensive water-quality sampling at Island Park Dam to identify the cause of high-turbidity events observed immediately downstream of the dam each of the past few summers. This study paired a water-quality sonde on the west side of the river with the existing HFF sonde on the east side. In addition, water quality samples were taken at various depths in the reservoir immediately upstream of the dam.
Four more sondes are scheduled for installation in 2016 in tributaries to the Henry’s Fork. The Foundation is pursuing potential partnerships that would allow installation of additional sondes in the Teton River watershed in future years, resulting in a network of a dozen or more stations that will be used to monitor water quality throughout the watershed for the next 20 years or more.
In 2016, HFF is also working with a graduate student from Indiana University who will be conducting his masters thesis on research related to water-quality in Island Park Reservoir. You can read a bit more about Jack below.
Hello! I'm Jack McLaren. I’m a student at the School of Public and Environmental Affairs at Indiana University, where I am getting two Master’s degrees; one in Public Affairs and one in Environmental Science. For my Master’s thesis I’m conducting a research project with the Royer Laboratory and HFF on how climate change and reservoir age influence water quality in reservoirs and their tailwaters. I’ll be taking a close look at Island Park Reservoir to see if nutrient and sediment levels in the reservoir and its tailwater have changed over time and if there’s any connection with climate change or the age of Island Park dam. I hope my research will be informative for conserving wild trout in the Henry’s Fork River!
I grew up in Denver, Colorado and I love fly-fishing, as well as camping, backpacking, and kayaking in my free time. I am excited to be working with HFF this summer and I hope to see you on the river!
Reconnecting Habitat: Fish Passage at Chester Dam
Chester Dam became a barrier to upstream fish passage when it was built in 1938. Chester Dam diverts water from the Henry’s Fork into the Crosscut Canal, which then delivers much of it to the Teton River. The Crosscut Canal was built to deliver water stored in Island Park Reservoir—on the Henry’s Fork—into the Teton River. This allows irrigators on the Teton River to have access to storage water late in the season when Teton River flows drop below what is needed to meet irrigation demand. Chester Dam also diverts water into the Last Chance Canal, which delivers irrigation water to the Egin Bench area west of St. Anthony.
In July of 2008, the Federal Energy Regulatory Commission (FERC) issued a license to hydropower developer Symbiotics of Rigby, Idaho, granting them permission to retrofit Chester Dam with a hydropower generating facility. The licensing and settlement agreement process presented an opportunity to improve fish passage so fish could move up through the dam to habitat above it, as well as improve recreational access.
Fish screens in both the Cross Cut and the Last Chance canals to keep fish from being lost from the river.
A fish ladder to provide upstream passage to fish habitat above the dam.
A screen on the hydropower turbine intake to prevent large fish from passing through.
Better river access, including improved boat launches above and below the dam and an expanded parking area.
Project partners and contributors: The Henry's Fork Foundation worked closely with Trout Unlimited and the Greater Yellowstone Coalition throughout the licensing process and these organizations are responsible for obtaining the funding for the design and construction of the fish ladder at the project. Other partners include: Idaho Department of Fish and Game, Caribou-Targhee National Forest, U.S. Fish and Wildlife Service, and Idaho Department of Parks and Recreation.
Reducing Sediment at Henry's Lake Outlet
Historic channel straightening and overgrazing—as well as a highly changed river flows—have affected Henry’s Lake outlet, resulting in the simplification of stream and riparian habitat and high erosion rates. The objective of the outlet restoration project is to reduce bank erosion at high flows and improve stream and riparian habitat in a 1-mile reach of the outlet on the Nature Conservancy’s Flat Ranch.
Stream channel assessment work was completed in 2003 and 2004, and water was first turned into the restored channel in October 2007. By the end of fall 2013, the project will be complete, after some final modifications are made to ensure that the project is compatible with pre-existing rights of the North Fork Reservoir Company to deliver storage water from Henry’s Lake downstream through the Outlet.
Project partners and contributors: Jackson Hole One Fly Foundation/National Fish and Wildlife Foundation Conservation Partnership, Idaho Department of Environmental Quality, the Flat Rock Club, the Gibbons Foundation, and the Trout and Salmon Foundation.
Long-Term Habitat Monitoring
n 1996, HFF began the Habitat Assessment Project, which collected information on aquatic and riparian habitat conditions, fish populations, and aquatic invertebrates on every reach of the Henry’s Fork and most of its tributaries. That project required five years to complete and provided a set of information that could serve as a baseline to compare with future conditions.
In 2000, a set of nine “indicator” sites were selected for long-term monitoring. Six of these are located on the main stem of Henry’s Fork from Mack’s Inn to Rexburg, and there is one site on each of three tributaries: Henry’s Lake Outlet, Sheridan Creek, and Fall River. These sites were monitored each year from 2001 through 2005, adding to the data collected during the 1990s.
The next round of monitoring will occur between 2015 and 2020, providing a 20-year comparison with data collected during the initial habitat assessment and a 10-year comparison with conditions in 2005.
Download the long-term monitoring report from 2005.
Hydrology and Water Management
The hydrologic regime of a river—defined as magnitude, timing, duration, frequency, and rate of change in river flow—is the primary physical driver of ecological processes in the stream channel and in the floodplain. These processes determine the quality and abundance of habitat for wild trout and other aquatic organisms. In regulated rivers like the Henry’s Fork, the hydrologic regime is determined by complex relationships among climate, geology, and how we use water. This includes interactions between groundwater and surface water.
Because of the importance of hydrologic regime to fisheries, hydrology and water management have been important components of HFF’s research program since the 1990s. Results of this research are used regularly by HFF and its collaborators to design water management strategies that benefit multiple resources and uses, including the river’s famous fisheries, irrigated agriculture, and municipal water supplies.
- Henry's Fork Basin Study (U.S. Bureau of Reclamation)
- Effects of Changes in Land Use on Water Resources
- Ecological Streamflow Needs in the Henry's Fork Watershed(PDF)
- The Influences of Geology and Water Management on Hydrology in the Henry's Fork (a thesis) (PDF)
- Hydrologic Alteration and its Ecological Effects in the Henry’s Fork Upstream of St. Anthony(PDF)
For more information about the HFF's Research and Restoration programs, please e-mail Dr. Rob Van Kirk.