Eroding Shoreline Threatens Historic Peale Island Cabin, Yellowstone National Park, Wyoming
Yellowstone National Park collaborated with the National Park Service Geologic Resources Division (NPS GRD) to examine the causes of shoreline erosion on Peale Island and to identify adaptation options for protecting the shoreline and a historic cabin on the island.
Peale Island is located in a wilderness area in the South Arm of Yellowstone Lake. It is composed of glacial till and has no source of new coarse sediment but does receive a minor supply of erodible fine sediments. Several processes may be accelerating shoreline erosion, including a change in sediment transport processes, tectonic uplift, longer ice-free periods, tree death, and changes in wave and wind patterns. Climate change has already affected the park in ways such as reduced annual snowpack, declining streamflow, increased stream temperature, and more frequent wildfire events. Ongoing climate change has the potential to drive several process changes: increased precipitation may raise Yellowstone Lake water levels and increase shoreline submergence; higher summer temperatures may increase evaporation that lowers water levels; and warmer temperatures may increase the number of ice-free days on Yellowstone Lake and cause a corresponding increase in exposure of the Peale Island shoreline to wind-driven waves and coastal erosion.
The park asked the NPS GRD to develop information about shoreline change on Peale Island and to clarify the options for the Peale Island Cabin and shoreline. The resulting natural resources report (Beavers et al. 2014) presented and described 10 coastal adaptation options:
- Increasing/improving public awareness, education, and outreach efforts
- Conducting/gathering additional research, data, or products
- Monitor, learn, and interpret the change: Continue current management practices
- Record, then let go: Deconstruct cabin
- Improve structure resiliency: Elevate cabin
- Indirect/offsite action: Nourish shoreline with compatible sediment
- Indirect/offsite action: Armor shoreline with rocks, logs, or other materials
- Relocate cabin to Peale Island interior
- Relocate cabin to outer shore of Yellowstone Lake
- Replace cabin function and structure
Many of the adaptation options suggest similar “no-regrets” actions, including monitoring shoreline position and lake water level; documenting the historic resource and cultural landscape; and monitoring the condition of the historic structure.
Outcomes and Conclusions
As of September 2014, the park intends to initiate a planning process for an alternative management option. The process will include screening of the potential project, discussions with the Wyoming State Historic Preservation Office and engagement in appropriate National Historic Preservation Act and National Environmental Policy Act processes to evaluate the project and make a final decision (Dave Hallac, Chief, Yellowstone Center for Resources, email, 21 October 2014). In summer 2015, alternate sites along the shores of the South Arm of Yellowstone Lake were evaluated to define suitable sites for potential relocation of the cabin.
Beavers, R., C. Schupp, I. Slayton, & M. Caffrey. (2015). Eroding Shoreline Threatens Historic Peale Island Cabin, Yellowstone National Park, Wyoming [Case study on a project of Yellowstone National Park]. Excerpted from Schupp, C.A., R.L. Beavers, and M.A. Caffrey [eds.]. 2015. Coastal Adaptation Strategies: Case Studies. NPS 999/129700. National Park Service, Fort Collins, Colorado. Retrieved from CAKE: www.cakex.org/case-studies/eroding-shoreline-threatens-historic-peale-i…;(Last updated November 2015)