Idaho Panhandle National Forests Watershed Specialist Review. Extraordinary Circumstances Review: Floodplains, Wetlands, Municipal Watersheds

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1 Idaho Panhandle National Forests Watershed Specialist Review Project: Idaho Buckhorn Restoration Burn Date: June 10, 2013 Extraordinary Circumstances Review: Floodplains, Wetlands, Municipal Watersheds Resource Present Potential Extraordinary Circumstance Effect Floodplains YES NO Occupation or modification of floodplains ( EO 11988) YES NO Wetlands YES NO Occupation or modification of wetlands ( EO 11990) YES NO Municipal Watersheds YES NO Actions in municipal watersheds (FSH , Chapter ) YES NO 1. Scope The purpose of this report is to evaluate the proposed project to determine whether there may be significant and adverse impacts to any of the following extraordinary circumstances described in FSH , Chapter : (b) Flood plains, wetlands, or municipal watersheds. In addition to evaluating whether or not the project qualifies for a Categorical Exclusion from documentation in an EA or EIS, this report provides documentation of the project s consistency with the 1987 Idaho Panhandle National Forests Plan and relevant State and Federal regulations. 2. Existing Conditions 1. Project Location: The Idaho Buckhorn resource area is about 7 miles north of Moyie Springs, Idaho and encompasses the eastern portion of the Deer Creek watershed including Keno, Faro, Mill, and Davis Creeks. 2. Need for the Project: The project proposes to improve wildlife habitat, provide opportunities to restore whitebark pine, and to reduce natural fuel accumulations. More details can be found in the scoping notice and project file. 3. Proposed Action(s): This project is proposing to complete prescribed burning on about 4000 acres distributed across 10 units. These units are primarily located on the south facing slopes of upper Deer, Keno, Faro, Mill and Davis Creeks. Ignition would be accomplished primarily with helicopter but certain areas may require hand ignition. Prescribed fires within the 10 units would be completed over the course of several years Design Criteria No additional design criteria, above those listed in the proposal, are proposed for water resources. Additional design criteria, above those listed in the proposal, are proposed for water resources. These criteria are attached to this document. 3. Environmental Consequences 1. Direct and Indirect Effects No direct or indirect significant, adverse effects to floodplains, wetlands, or municipal watersheds are proposed or expected for this project.

2 3.1.1 Water Yield and Peak Flows: Watershed processes are very complex and exist with large amounts of natural variability (Elliot and Glaza 2007). Generally, removal of forest canopy through stand-consuming fires, forest insects and disease, or timber harvesting can increase water yield and modify hydrographs (i.e. increased peak flows or altered base flows). The hydrologic effects of prescribed burning are largely a function of fire severity and area burned. High severity burns that consume protective litter and expose mineral soil, kill vegetation, and remove canopy cover generally increase runoff and sediment yields, whereas low severity burns that only consume the upper litter layers have much less hydrologic impact. No impact to water yield would be expected from this project because the prescribed fires implemented would be a mosaic of severities with the majority being low to moderate intensity. The prescribed fires would have specific criteria to limit the severity of the fires included in the burn plans such as; constraints on fuel, duff, and soil moistures, weather conditions such as relative humidity, areas to exclude ignition, etc. Fire intensity would be further controlled and adjusted during implementation by modifying the patterns of ignition. Additionally, burns would likely be initiated a short time before wet weather is expected. Troendle et al report that since low severity prescribed fires do not cause a high degree of tree mortality or litter combustion, the effects on evapotranspiration and forest floor water storage are generally too small to change watershedscale water yields. This same publication summarizes numerous studies which confirm that light to moderate prescribed fire has little effect on streamflow Sediment Yield Sediment yield to streams is a natural process and includes events such as landslides and wildfires. These events can deliver tremendous amounts of sediment but are stochastic in nature and occur infrequently over time. Transport of sediment plays a fundamental role in the natural function of forested watersheds. In excess, suspended sediment degrades aquatic and fish habitat, disrupts hyporheic connection, enhances the transport of sorbed pollutants, and increases treatment costs associated with municipal water withdrawal (Rehg et. al. 2005). Forests generally have very low erosion rates unless they are disturbed (Elliot et. al. 2000). Prescribed fires have the potential to increase erosion by removing the protective litter that covers the underlying mineral soil. A negligible increase in sediment yield to streams would be expected from this project. The surface condition after a prescribed fire is typically a mosaic-like pattern of low severity, high severity, and unburned patches (Robichaud 2000). The patterns of burn severity help control the spatial scale at which the effects of prescribed burning can be detected (Troendle et al. 2010). The patchiness of burn severity allows unburned and low severity patches to infiltrate runoff and trap sediment that is generated on adjacent high severity patches (Biswell and Schultz 1957; Cooper 1961; Swift and others 1993). This project would include design criteria which excludes ignition within RHCAs. This would limit the fire severity and subsequent consumption of litter and surface roughness which traps sediment before it is delivered to the stream. Fire would be allowed to back into RHCAs but the intensity would be expected to diminish due to the increased shade, humidity, and fuel moistures found in riparian areas; and would be expected to have generally beneficial results. Dwire and Kauffman 2003 reported that prescribed fire may top kill certain riparian trees and shrubs but is unlikely to negatively affect belowground structure. This indicates the bank-stabilizing properties of the riparian vegetation is preserved and the trees, shrubs and forbs would recover quickly. Potential sediment delivery was also modeled using Web WEPP Watershed tool (W³). The model is in a development phase and can be accessed at The W³ tool is a web-based map interface linked to the FS Water Erosion Prediction Project (WEPP) model. W³ allows the user to enter site specific forest management parameters (including soils, topography, climate, surface conditions, etc) and the model creates a graphic output showing average annual erosion and sediment delivery values at the watershed scale. The model was run for the subwatersheds that are located within the project area including; Davis, Mill, Faro, and Keno

3 Creeks. In correlation with the research cited above, the model indicates that areas of increased erosion are possible at the hillslope scale, however, few of the areas of increased erosion have the topography required to deliver the sediment to the stream network. The model outputs should be considered a worst case scenario because the simulation emulates conditions immediately after a prescribed fire where no vegetative recovery has occurred. This type of condition would be short lived since vegetation and groundcover (i.e. needle cast from dead trees, etc.) would be expected to recover shortly after the fire. All modeling data can be found in the project file Stream Temperatures Currently, Deer Creek is 303(d) listed as impaired for temperature from source to mouth in the 2010 IDEQ Integrated Report. Until a TMDL is created for Deer Creek, the pollutant of concern should remain constant or decrease (e.g. maintain or decrease water temperature in these streams).fuel reduction treatments [prescribed fire] could potentially affect water temperature by altering vegetative shade that attenuates the input of solar radiation to streams. Direct sunlight warms streams, particularly during periods of low flow (Dwire et al. 2010). No increase in stream temperatures would be expected from implementation of this project because shade-providing riparian vegetation would be preserved. Project design features would exclude fire ignition within RHCAs. With direct ignition excluded, the conditions (cooler temperatures, higher humidity and fuel moistures, etc.) found adjacent to streams would limit the intensity of fire burning within the riparian areas which would reduce vegetation mortality thereby preserving shade. Many riparian species appear to be fairly resilient to disturbance, particularly fire (Dwire and Kauffman 2003). Additionally, vegetative disturbance that does occur as a result of fire would be of short duration as shrubs, grasses, and forbs recover within one growing season. Cumulative Effects Past, present and reasonably foreseeable activities No cumulative significant, adverse effects to floodplains, wetlands, or municipal watersheds are proposed or expected for this project. Cumulative effects would be most noticeable at the site scale (if they occur), becoming progressively less discernible at the sub-watershed, watershed, and subbasin scales. Given the low degree of anticipated site-level effects, cumulative effects are expected to be negligible. 4. Regulatory Framework: Executive Orders and (Floodplains and Wetlands) Floodplains: The Project will not modify or occupy floodplains to an extent greater than already exists. As such, there will be no adverse impacts to floodplains; thereby complying with EO and FSH , Chapter Wetlands: The Project does not propose to modify or destroy wetlands. As such, the Project will not adversely affect wetlands; thereby complying with EO and FSH , Chapter Municipal Watersheds: The project will not adversely affect municipal watersheds; thereby complying with FSH , Chapter Clean Water Act, Safe Drinking Water Act, and State Water Quality Laws: The proposed project is also consistent with all applicable State and Federal water quality laws because project Design Criteria and BMPs have been included to protect water resources.

4 Clean Water Act: Sections 303(d), 305(b) Impaired Waters and TMDLs Watershed (HUC6) of proposed project: Is the watershed on Idaho s 303(d) Impaired Waters List? YES NO If YES: Is the pollutant/issue excess sediment? YES NO If YES: Are ground disturbing activities proposed? YES NO If YES: Are BMPs or Design Criteria included to minimize/eliminate sediment delivery to WOTUS? YES NO If YES: Is the pollutant/issue excess temperature? YES NO If YES: Is vegetation or canopy cover removal proposed? YES NO Will the proposed project likely result in further impairment of the watershed? YES NO Reason: See discussion in Direct and Indirect effects section. Multiple-Use Sustained-Yield Act: The proposed project is consistent with the intent of the Multiple-Use Sustained-Yield Act of 1960, which states that management of the National Forests must provide "sustained yields in perpetuity without impairment of the productivity of the land", because watershed functions are not expected to be impaired. National Forest Management Act: The proposed project is consistent with the intent of the NFMA because project activities will not irreversibly damage water resources and project Design Criteria and BMPs have been included to protect water resources. Forest Plan Consistency:The Forest Plan objective for Water Quality is: The current Idaho Water Quality Standards will be met or exceeded. This will be accomplished through application of bestmanagement practices. The proposed project is consistent with the standards, goals, and objectives for water resources set forth in the Idaho Panhandle National Forest Plan (USDA, 1987) because project Design Criteria and BMPs have been included to protect water resources. BMPs include Soil and Water Conservation Practices (FSH ) used to control non-point source pollution and protect water resources from permanent damage. SIGNATURE OF PREPARER I certify that the contents of this report are true and accurate, to the best of my knowledge. Questions about this specialist report can be addressed to Brandon Glaza, North Zone Hydrologist, /s/ Brandon Glaza 10 June 2013 Hydrologist Date

5 References: Biswell, H.M.; Schultz, A.M Surface runoff and erosion as related to prescribed burning. Journal of Forestry. 55: Cooper, C.F Controlled burning and watershed condition in the White Mountains of Arizona. Journal of Forestry. 59: Dwire, K.A.; Kauffman, J.B Fire and riparian ecosystems in landscapes of the western USA. Forest Ecology and Management. 178 (1-2): Dwire, K., Rhoades, C., Young, M Potential Effects of Fuel Management Activities on Riparian Areas. In: Elliot, William J.; Miller, Ina Sue; Audin, Lisa. Eds Cumulative watershed effects of fuel management in the western United States. Gen.Tech. Rep. RMRS-GTR-231. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Elliot, et.al Disturbed WEPP Interface for Disturbed Forest and Range Runoff, Erosion and Sediment Delivery. U.S.D.A.Forest Service Rocky Mountain Research Station and San Dimas Technology and Development Center. Elliot and Glaza Variability in runoff and erosion from small forested watersheds. ASABE conferenceproceedings. Elliot, William J.; Miller, Ina Sue; Audin, Lisa. Eds Cumulative watershed effects of fuel management in the western United States. Gen. Tech. Rep. RMRS-GTR-231. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 299 p. Swift Jr., L.W.; Elliot, K.J.; Ottmar, R.D.; Vihnanek, R.E Site preparation burning to improve southern Appalachian pine-hardwood stands: Fire characteristics and soil erosion, moisture, and temperature. Canadian Journal of Forest Research. 23: Rehg, K.J., A.I. Packman, and J. Ren Effects of suspended sediment characteristics and bed sediment transport on streambed clogging. Hydrol. Process. 19: Robichaud, P.R Fire effects on infiltration rates after prescribed fire in Northern Rocky Mountain forests, USA. Journal of Hydrology. 231: Troendle, C., MacDonald, L., Luce, C.,Larsen, I Fuel Management and Water Yield. In: Elliot, William J.; Miller, Ina Sue; Audin, Lisa. Eds Cumulative watershed effects of fuel management in the western United States. Gen. Tech. Rep. RMRS-GTR-231. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.