Mike Ryan RMRS

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Mike Ryan (RMRS)
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Protecting CriticalColorado Source Watersheds
from Severe Wildfires
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Buffalo Creek Fire May 18, 1996 11
miles in 4 ½ hours 11, 900 acres
burned Followed by Rain events Severe
Erosion and Flooding
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Colorados Front Range Watershed Protection
Working Group

• Objective
• To organize the work group to address the next
  steps in developing a Front Range Critical
  Watershed Wildfire Protection Strategy utilizing
  input and involvement of water providers, FRFTP
  Roundtable, state and federal agencies and other
  key water representatives.

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Data Refinement Work Group
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Data Refinement Work Group Goal 1

• Develop and adopt a clear and common methodology
  for identifying 6th level watersheds that are
  important /essential critical watersheds for
  water supply.

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(No Transcript)
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Upper South Platte 6th Level Watersheds
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Components

• Wildfire Risk
• Flooding or Debris Flow Risk
• Soil Conditions
• Water Uses

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1. Wildfire Risk

• Pinchot Report Analysis
• Western Colorado Wildfire Risk Assessment

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Upper South Platte Watershed Pinchot Wildfire
Risk
LowModerateMod-HighHighVery High
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2. Flooding or Debris Flow Risk

• Ruggedness or Slope
• Road Density

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Upper South Platte Watershed Flooding/Debris Flow
Risk
LowModerateMod-HighHighVery High
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3. Soil Conditions

• SSURGO or STATSGO
• K factor and slope
• Adjusted for geology

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Upper South Platte Watershed Soil Erosion Risk
LowModerateMod-HighHighVery High
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4. Water Uses

• Nodes - Reservoirs, Diversions and Sources
• Source Water Protection Areas
• Water Supply Reservoirs

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Overall Ranking
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Upper South Platte Watershed Composite Hazard
LowModerateMod-HighHighVery High
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Upper South Platte Watershed Final Priority
LowModerateMod-HighHighVery High
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Zones of Concern

• 5 stream miles based on State Statute
• 11 stream miles based on Buffalo Creek experience
• 15 radial miles based on SWAP
• RiverSpill model results

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Upper South Platte Watershed Zones of Concern
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Upper South Platte Watershed Final Prioritywith
Zones of Concern
LowModerateMod-HighHighVery High
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