Water Resources Research Act Program

Details for Project ID 2012WA367G

Predicting the impacts of climate change on post-fire sediment generation to explore post-fire restoration strategies and associated costs

Institute: Washington
USGS Grant Number:
Year Established: 2013 Start Date: 2012-08-16 End Date: 2015-08-15
Total Federal Funds: $249,718 Total Non-Federal Funds: $251,579

Principal Investigators: Jennifer Adam, Michael Barber, Barry Green, Balasingam Muhunthan, Molly Wood

Abstract: Wildfires can dramatically alter the landscape and create significant environmental hazards long after the immediate threats to life and property have been eliminated. Alteration of overland flow characteristics can lead to altered runoff hydrographs and severe aquatic habitat disturbances associated with increased soil erosion. Unfortunately, these water quantity and quality problems are expected to worsen. There is strong scientific evidence indicating climate change is expected to increase the frequency, duration, and intensity of extreme temperature and precipitation events and thus negatively impact associated heat wave, drought, flood, and wildfire phenomena. Thus, understanding the ramifications, linkages, and uncertainties of climate-induced variations in these extreme events related to hydrology and wildfires is paramount to adopting adequate plans, policies, and procedures aimed at protecting human and ecosystem health. To protect fish habitat, water quality, public safety, and public property, artificial restoration of wildfire sites is often conducted. There are, however, a considerable number of questions concerning artificial restoration in terms of both restoring environments to natural conditions and overall efficacies. In a time of financially-constrained budgets, a more robust scientifically-based methodology must be developed for determining when artificial versus natural restoration should take place. Our long-term goal is to predict the adverse water-quality impacts due to extreme wildfires and associated runoff erosion and mass wasting activity under projected climatic changes across the western US, and to quantify the efficiency and costs of fire-restoration strategies for the protection and enhancement of water quality in a changing climate. The overarching goal for this particular proposal is to develop a watershed-scale post-fire sediment generation prediction framework to explore the relative effects of fire-restoration strategies and changes in extreme rainfall events across a range of topographic, soil, and land cover conditions, and to use scenario simulations to develop relationships between watershed characteristics, burn severity, fire-restoration strategies, and economic costs to inform management decisions at local to national scales. For model testing, we will use watersheds within the Salmon River basin (SRB) of Idaho as prior studies have suggested that post-fire erosion in the region may be contributing significant amounts of sediment to downstream water bodies. The specific objectives of this project are to 1. Identify changes in extreme rainfall events for a range of future climate scenarios. 2. Characterize burn severity and vegetation regrowth characteristics. 3. Predict changes in sediment generation from post-fire erosion and mass failures as impacted by changes in extreme rainfall events for watersheds with varying burn intensities. 4. Assess the economic impacts of artificial versus natural restoration efforts needed to reduce post-fire sediment delivery to streams and protect water quality. State, federal, and private forest managers continually develop strategic plans evaluate the effectiveness of alternative fire management strategies with respect to the specific goals and objectives identified for forested areas. The models developed and tested by this research will enable resource managers to better understand ecosystem responses and risks associated with forest fires under climate change and extreme events. Information dissemination will occur through the standard academic routes of conferences, seminars, and publications. We will also build a project-specific webpage with interactive tools based on the relationships developed with the modeling activities; and we will present our new tools at a forest manager outreach workshop.