Lecture on Fire Impact on Water Resources

Introduction

• Focus: Impact of fires on watersheds and water resources
• Importance: Watersheds provide drinking water and support aquatic habitats
• Impacts can be both physical and chemical

Physical Impacts of Fire

• Vegetation burn affects soil's ability to retain water
• Changes in streamflow records and events
• Mass soil loss due to vegetation depletion
• Soil becomes hydrophobic, increasing runoff

Chemical Impacts on Water Quality

• Soil erosion leads to higher turbidity and suspended solids
• Increase in carbon, nitrogen, and phosphorus loads
• These changes affect dissolved oxygen levels

Infrastructure Implications

• Debris can block streams and intakes
• Sediment runoff fills reservoirs
• Clogging of water intakes

Regional Concerns: Pacific Northwest

• Limited historical fire data, especially west of the Cascades
• Need for better data and tools for water managers

Fire Earth Project

• NSF-funded project led by University of Idaho
• Collaboration with University of Nevada, WSU, UW, UC Santa Barbara
• A modeling framework: ecohydrologic, biogeochemical, soil erosion, and fire spread models
• Aim: Understand watershed-scale fire impacts

Needs Assessment

• Focus on improving data and tools for water managers
• Collaboration with 12 water providers serving 6 million people in BC, Washington, and Oregon

Focus Group Findings

• Fire concerns include: location, detection, pre/post-fire management
• Biophysical and institutional concerns
• Biophysical: forest health, water quality parameters, infrastructure
• Institutional: management partnerships, public/political support

Management Strategies

• Reliance on constituent support, capital, system knowledge, ownership degree
• Some utilities invest in modeling, fuel management, fire detection
• Others build partnerships with land management entities

Data Needs

• Monitoring climatic and biophysical conditions at watershed scale
• Need for pre-fire mitigation data and post-fire impact understanding

Conclusion

• Goal: Enhance utility response to fire impacts, improve public communication
• Encouragement for further research on under-explored fire and water management topics

Q&A Session

• Discussion on fire retardant impact on water quality
• Concerns over fire management strategies and their effectiveness
• Importance of public health considerations in water quality post-fire

Additional Discussions

• Example of successful fire management in Sholo, Arizona
• Communication challenges with taxpayer investments in fire mitigation