Forests are interconnected with rivers and watersheds. With a changing climate and prolonged drought, Colorado is seeing an increase in frequency, intensity, and impact of wildfires across the state. Rivers and riparian areas are important in minimizing the impacts of fire by serving as fire breaks, providing buffer zones to filter runoff, and offering important wildlife corridors. However, post-fire conditions can negatively impact stream conditions. For example, flash floods producing hillslope erosion and mud and debris flows can cause water quality impairments, exacerbate fluvial hazards, and stress or completely devastate aquatic communities. Understanding the potential impacts of fire before they inevitably occur is integral to making stream management decisions in fire-prone watersheds. Information is needed to demonstrate where there are values that may need protection, high risk areas, and potential mitigation strategies. Additionally, stakeholders across the state have questions as to how changing forests and climate change will impact the hydrologic cycle in their basin. Research is ongoing as to the impacts of forests and fire on snowpack, evapotranspiration, sublimation, and runoff conditions.
As a result, incorporating aspects of forest health and post-fire modeling and assessment can be beneficial to an SMP/IWMP planning effort. However, this can be a challenging and sometimes overwhelming endeavor. As many SMP/IWMP coalitions are considering how best to incorporate forest assessments in their processes, forest health and watershed health planning continues to evolve and present new opportunities for effectively integrating these components into SMP/IWMP processes.
Leah Weaver collecting a benthic macroinvertebrate sample on the Conejos River (Daniel Boyes/Rio Grande Headwaters Restoration Project)
The Colorado Water Conservation Board has taken steps to help support SMP/IWMP coalitions and Basin Roundtables as they grapple with these plan scoping questions. Resources include:
These examples outline various approaches that SMP/IWMPs have taken to incorporate forest and fire information into their assessment and planning process. The examples vary in scale based on the SMP/IWMP’s resources, stakeholder interests, budget, and other factors.
Upper San Juan River Watershed Enhancement Partnership
For more information, please view an April 2022 peer-learning call presentation on this topic.
St. Vrain and Left Hand SMP
The St. Vrain and Left Hand SMP utilized a USFS Wildfire Hazard Potential modeling approach derived from LANDFIRE (Landscape Fire and Resource Management Planning Tools) to map the wildfire risk in the watershed to inform decisions on managing for the conservation targets identified in the SMP. LANDFIRE is a shared program between the wildland fire management programs of the US Forest Service and Department of Interior, providing landscape scale geo-spatial products to support cross-boundary planning, management, and operations. The specific dataset utilized by St. Vrain Left Hand was developed by USFS Gregory Dillon and Julia Gilbertston-Day with background data, documentation and metadata to describe the approach. Conservation targets identified in the SMP include key plant, macroinvertebrate, wildlife, and fish species in each watershed zone in addition to key stressors such as wildfire potential, climate change, and invasive species. The “very high” and “high” categories in the wildland fire potential data layer were used. Priority opportunity areas were then identified where high fire risks occurred in the vicinity of high value habitat areas along the creek. In addition, improved forest fire management was highlighted as a need, particularly where sources of drinking water are at most risk (e.g., around the reservoir).