1.2. Watershed Resilience
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Upper Poudre Watershed Resilience Plan Final Milton Seaman Reservoir Resilient Pine Cones Upper Cache La Poudre River January 2017 Prepared for Coalition for the Poudre River Watershed Prepared by JW Associates Inc. Upper Poudre Resilience Watershed Plan Final Table of Contents 1. Summary .............................................................................................................................................. S-1 2. Introduction ............................................................................................................................................ 1 1.1 Why Resilience is Important ..........................................................................................................................1 1.2 Watershed Resilience ....................................................................................................................................1 1.3 Geographic Scope of the Plan ......................................................................................................................3 1.4 Stakeholder Process .....................................................................................................................................5 1.5 Values for Analysis ........................................................................................................................................6 1.5.1 Value A Resilient Upland Habitats .....................................................................................................6 1.5.2 Value B - Resilient River Corridor .......................................................................................................7 1.5.3 Value C - Reliable Water Supply ........................................................................................................ 7 2. Resilient Conditions .................................................................................................................................9 2.1 The Impact of Climate Change and Future Conditions ...............................................................................9 2.2 Resilient Conditions for Value A - Resilient Upland Habitat .......................................................................9 2.2.1 Forest Life Zones ...............................................................................................................................9 2.2.2 VeGetation Types of the Upper Poudre Watershed ........................................................................10 2.2.3 Forest VeGetation Type Resiliency Descriptions ..............................................................................11 2.3 Resilient Conditions for Value B - Resilient River Corridor ........................................................................15 2.3.1 Stream Channel Equilibrium ............................................................................................................16 2.3.2 Sediment Transport and Deposition ...............................................................................................16 2.3.3 Floodplain and Riparian Function ...................................................................................................17 2.3.4 Aquatic Habitat ...............................................................................................................................18 2.3.5 Roads ..............................................................................................................................................19 2.4 Resilient Conditions for Value C - Reliable Water Supply ..........................................................................19 2.4.1 Land Use History and Affect on the Watershed .............................................................................. 20 3. Resiliency Analysis .................................................................................................................................23 3.1 Ranking/Categorization Approach .............................................................................................................23 3.2 Value A - Resilient Upland Habitat .............................................................................................................23 page iP Upper Poudre Resilience Watershed Plan Final 3.2.1 Factor 1 - Canopy Closure .................................................................................................................24 3.2.2 Factor 2 - Comparison of Forest Types to Resilient Conditions .......................................................28 3.2.3 Factor 3 - Wildfire Hazard ...............................................................................................................30 3.2.4 Value A - Resilient Upland Habitat Composite RankinG ..................................................................33 3.3 Value B - Resilient River Corridor ...............................................................................................................34 3.3.1 Factor 1 - Roads ...............................................................................................................................35 3.3.2 Factor 2 - Debris FloW Hazard .........................................................................................................38 3.3.3 Factor 3 - Soil Erodibility/Granitic Parent Material Hazard .............................................................39 3.3.4 Factor 4 - Sediment Transport ........................................................................................................43 3.3.5 Value B - Resilient River Corridor Composite RankinG ....................................................................48 3.4 Value C - Reliable Water Supply .................................................................................................................49 3.4.1 Factor 1 - Land Use Impacts on Water Quality ................................................................................50 3.4.2 Factor 2 - ExistinG Water Quality Impairment .................................................................................51 3.4.3 Factor 3 - Source Supply Areas .......................................................................................................52 3.4.4 Factor 4 - Sediment Deposition ......................................................................................................54 3.4.5 Value C - Reliable Water Supply Composite RankinG ......................................................................56 3.5 Overall Watershed Priority Analysis ........................................................................................................... 57 4. Priority Watershed Targets and Treatments ....................................................................................... 59 4.1 Priority Watershed Target Areas ................................................................................................................ 59 4.2 Actions to Increase Watershed Resilience ................................................................................................59 4.2.1 Forest/VeGetation ManaGement .................................................................................................... 60 4.2.2 ManaGinG Wildland Fire .................................................................................................................. 62 4.2.3 Road ManaGement ......................................................................................................................... 62 4.3.4 Riparian and Floodplain Restoration ............................................................................................. 63 4.3 Horsetooth Reservoir Target Area ............................................................................................................ 63 4.3.1 Summary of Conditions in the Horsetooth Reservoir TarGet Area ................................................. 63 4.3.2 TarGeted Actions in the Horsetooth Reservoir Watershed TarGet Area ........................................ 65 4.4 Lone Pine Creek Target Area ..................................................................................................................... 67 4.4.1 Summary of Conditions in the Lone Pine Creek TarGet Area .......................................................... 67 4.4.2 TarGeted Actions in the Lone Pine Creek TarGet Area ................................................................... 68 4.5 Lower Poudre - Hill Gulch Target Area ...................................................................................................... 70 page iiP Upper Poudre Resilience Watershed Plan Final 4.5.1 Summary of Conditions in the LoWer Poudre - Hill Gulch Target Area ........................................... 70 4.5.2 TarGeted Actions in the LoWer Poudre - Hill Gulch Target Area ..................................................... 72 4.6 Meadow Creek Target Area ....................................................................................................................... 73 4.6.1 Summary of Conditions in the MeadoW Creek Target Area ........................................................... 73 4.6.2 TarGeted Actions in the MeadoW Creek Target Area ..................................................................... 75 4.7 Pennock Creek Target Area ........................................................................................................................ 77 4.7.1 Summary of Conditions in the Pennock Creek Target Area ...........................................................