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Section 3.4 – Water Resources

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SECTION 3.4

WATER RESOURCES_______________________

I. INTRODUCTION The following issue was identified from public comment during scoping for this project:

• What are the effects of the proposed activities on hydrologic processes and water resources; specifically water yield, sedimentation, and channel, floodplain and wetland function?

The units of measure for this issue are equivalent clear-cut area (ECA) acres, number of new stream crossings, miles of road/trail reconstruction and maintenance, and miles of new system or temporary road. The threshold for this issue is: Greater than 50 percent of 6 Hydrological Unit Code (HUC) watersheds in ECA (Stednick 1996).

The analysis area for water resources includes watersheds at the 6 HUC level. There are five – 6 HUC watersheds ranging in size from 14,298 acres to 39,175 acres that surround the BCLMP area. Refer to Appendix A, Map 20, Sixth Level Watersheds Intersecting Project Boundary. Refer to section B. ASSUMPTIONS, METHODOLOGY AND SCIENTIFIC ACCURACY OF INFORMATION USED for more detail on the analysis methods.

A. REGULATORY FRAMEWORK Federal Clean Water Act (CWA) This Act requires Federal Agencies to comply with all Federal, State, and local requirements, administrative authority, process and sanctions related to the control and abatement of water pollution (CWA, Sections 313(a) and 319(k), USC 2002). The CWA gives authority to individual States to develop, review, and enforce water quality standards under Section 303. This section also requires the States to identify existing water bodies that do not meet water quality standards, and develop plans to meet them. These plans are commonly called TMDL's (total maximum daily load) and are discussed further below. Section 404 of the Act gives authority to the Corps of Engineers to review and permit activities that may impact navigable waters of the U.S. National Pollutant Discharge Elimination System (NPDES) Permits - The Custer National Forest acknowledges this emerging issue and will obtain all necessary permits prior to project implementation.


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Forest and Rangeland Renewable Resource Planning Act of 1974 and National Forest Management Act of 1976 In response to requirements set forth in these two Acts, final rules on National Forest System Land and Resource Management Planning established specific minimum management requirements to be met in accomplishing the goals and objectives for National Forest System lands. These requirements were intended to guide the development, analysis, approval, implementation, monitoring, and evaluation of forest plans. Requirements specific to soils, water and fish habitat are found in 36 CFR 219.27, volume 47, #190, 09/30/82 (Federal Register 1982) as follows: (a) Resource protection. “All management prescriptions shall:

(1) Conserve soil and water resources and not allow significant or permanent impairment of the productivity of the land; (2) Consistent with the relative resource values involved, minimize serious or long-lasting hazards from flood, wind, wildfire, erosion. (4) Protect streams, streambanks, shorelines, lakes, wetlands, and other bodies of water...; (6) Provide for adequate fish and wildlife habitat to maintain viable populations of existing native vertebrate species....”

(e) Riparian areas. “Special attention shall be given to land and vegetation for approximately 100 feet from the edges of all perennial streams, lakes, and other bodies of water. This area shall correspond to at least the recognizable area dominated by the riparian vegetation. No management practices causing detrimental changes in water temperature or chemical composition, blockages of watercourses, or deposits of sediment shall be permitted within these areas that seriously and adversely affect water conditions or fish habitat. Topography, vegetation type, soil, climate conditions, management objectives, and other factors shall be considered in determining what management practices may be performed within these areas or the constraints to be placed upon their performance.” (f) Soil and Water Conservation. “Conservation of soil and water resources involves the analysis, protection, enhancement, treatment, and evaluation of soil and water resources and their responses under management and shall be guided by instructions in official technical handbooks. These handbooks must show specific ways to avoid or mitigate damage, and maintain or enhance productivity on specific sites. These handbooks may be regional in scope or, where feasible, specific to physiographic or climatic provinces.” Refer to Appendix C for a discussion of the Forest Service Soil and Water Conservation Practices Handbook.

Multiple Use Sustained Yield Act of 1960 It is the policy of the Congress that the national forests are established and shall be administered for outdoor recreation, range, timber, watershed, and wildlife and fish purposes (16 USC 2 (I); Sec 528). The terms multiple use and sustained yield are defined as:


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“The management of all the various renewable surface resources of the national forests so that they are utilized in the combination that will best meet the needs of the American people; making the most judicious use of the land for some or all of these resources or related services over areas large enough to provide sufficient latitude for periodic adjustments in use to conform to changing needs and conditions; that some land will be used for less than all of the resources; and harmonious and coordinated management of the various resources, each with the other, without impairment of the productivity of the land, with consideration being given to the relative values of the various resources, and not necessarily the combination of uses that will give the greatest dollar return or the greatest unit output (multiple use).” “The achievement and maintenance in perpetuity of a high-level annual or regular periodic output of the various renewable resources of the national forests without impairment of the productivity of the land (sustained yield).”

State of Montana

Water Quality Law

As directed by the Clean Water Act, the State of Montana developed a water quality classification system, developed water quality standards to be applied to various water classes, and identified water bodies that do not meet standards. The Montana Department of Environmental Quality (MTDEQ) has classified all waters within the analysis area as C-3 waters. The beneficial uses associated with this classification include; bathing, swimming, and recreation; growth and propagation of non-salmonid fishes and associated aquatic life, waterfowl, and furbearers. The quality of these waters is naturally marginal for drinking, culinary and food processing purposes, agricultural and industrial water supply. Degradation, which will impact, established beneficial uses will not be allowed. (Administrative Rules of Montana (ARM) 17.30.611 2009).

Surface Water Quality Standards

The Montana Water Quality Act, Surface Water Quality Standards require that land management activities must not generate pollutants in excess of those that are naturally occurring, regardless of the stream’s classification. Under ARM 17.30.629 (2) (f) “No increases are allowed above naturally occurring concentrations of sediment, settleable solids, oils, or floating solids, which will or are likely to create a nuisance or render the waters harmful, detrimental, or injurious to public health, recreation, safety, welfare, livestock, wild animals, birds, fish, or other wildlife.” Naturally occurring is defined in ARM 16.20.603 as: “the water quality condition resulting from runoff or percolation, over which man has no control, or from developed lands where all reasonable land, soil and water conservation practices have been applied”. Reasonable land, soil and water conservation practices are similar to Best Management Practices (BMP’s). BMP’s is considered reasonable only if beneficial uses are fully supported. BMP’s are further discussed in Appendix C.


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Total Maximum Daily Load Waterbody List

Riparian and stream conditions are assessed by the Montana Department of Environmental Quality to determine the level of beneficial uses support. Streams that do not fully support their uses do not meet water quality standards. The status of water quality assessments and Total Maximum Daily Load (TMDL) development of streams are identified in a biennial report from MTDEQ. The Tongue and Powder River basins are located downstream from the analysis area and are currently in a pre-TMDL development stage. Beaver and Little Pumpkin Creek are listed on the 2008/2010 (draft) Montana 303(d) List, but fall under Water Quality Category 3: Insufficient data to assess any use (MTDEQ 2008/2010 (draft)). No probable causes or sources are currently identified, because assessments have not been completed. East Otter Creek is not specifically on the 303(d) List. However, Otter Creek, downstream from the analysis area, is listed as a Category 5 stream (requires a TMDL) because it does not support agriculture, aquatic life or warm water fishery. The impaired segment is identified as headwaters to mouth (confluence with Tongue River), although nearly the entire mainstem of Otter Creek and the East Fork Otter Creek are below the forest boundary. Probable causes for impairment in Otter Creek are alterations in streamside vegetative cover, iron, salinity and solids (suspended/bedload). Probable sources for impairment in Otter Creek are agriculture, grazing in riparian areas, highways/roads/bridges, site clearance (land development) and natural sources. Probable sources that could be on National Forest System (NFS) land include grazing in riparian areas, roads and natural sources. It is important to understand that the State of Montana has the authority to develop TMDL's. On streams with mixed ownership, the Forest Service cooperates with the State and other adjacent landowners in the development process. Additionally, the fact that a particular stream is listed does not preclude management activities from taking place. Montana Code Annotated (MCA 2009) 75-5-703(10)(c), states: (10) Pending completion of a TMDL on a water body listed pursuant to MCA 75-5-702: (c) new or expanded non-point source activities affecting a listed water body may commence and continue their activities provided those activities are conducted in accordance with reasonable land, soil, and water conservation practices.

Streamside Management Zone (SMZ) Law and Rules

The Montana Legislature passed the SMZ Law in 1991 and it became effective in 1993. This law prohibits certain forestry practices, e.g., equipment operation and broadcast burning, within 50 to 100 feet of streams. It specifies other criteria, e.g., retention tree requirements and road construction limitations, for this management zone (ARM 36.11.301). Refer to the section below on BMP’s for discussion of the SMZ Law in relation to this project.

Stream Protection Act – SPA 124

The Montana legislature enacted the Stream Protection Act in 1965. It requires all government agencies (Federal, State and local) to notify the State of all planned activities that will alter the bed or banks of any intermittent or perennial stream (MCA 87-5-502). The Montana Department of Fish, Wildlife and Parks administers this Act on Federal land through the SPA 124 permit process. Refer to the section below on BMP’s for a discussion of potential permits specific to the action alternatives.


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Forest Service

Custer National Forest Land and Resources Management Plan

Management goals for soil, water and riparian resources are identified in the Forest Plan under Chapter II - Forest Wide Management Direction and Chapter III – MA Direction (USDA 1986). The Forest Plan goal for watershed management is to: “[E]nsure that soil productivity is maintained and that water quality is maintained at a level which meets or exceeds state water quality standards.” (Page 4) Forest Plan objectives for soil and water resources are: “Continue to produce water that meets State water quality standards. National Forest System lands will be managed so that the soil and watershed conditions are in a desirable condition and will remain in that condition for the foreseeable future. Soil and water quality objectives are designed to assure that these resources meet State water quality objectives and BMP's are incorporated to assure this.” () Forest Plan goal for riparian areas include: “[M]anage for water quality, provide diverse vegetation, and protect key wildlife habitat in these areas from conflicting uses and uses and activities that adversely impact these areas will be mitigated.” (Page 3) Forest Plan objectives for riparian areas include recognition of their unique values, and management direction is to be designed to protect these key wildlife habitats and improve water quality: “[T]hese areas will be managed in relation to various legally mandated requirements including, but not limited to, those associated with floodplains, wetlands, water quality, dredged and fill material, endangered species, and cultural resources.” (Page 5) Goals for MA M (Riparian) are: “Manage to protect from conflicting uses in order to provide healthy, self-perpetuating plant and water communities that will have optimum diversity and density of understory and overstory vegetation.” (Page 80)

Best Management Practices

As identified above under Surface Water Quality Standards, soil and water conservation practices (or BMPs) are the primary mechanism to minimize water quality impacts from non-point source pollution and still allow dispersed land management activities to occur on National Forest land. To reach these objectives the Forest Service developed the R1/R4 Forest Service Soil and Water Conservation Practices Handbook (USDA 1988, major revision in progress). Refer to Appendix C for a discussion of this handbook, and the soil and water conservation practices applicable to this project. Region 1 Forest Service has also embraced the Montana Forestry Best Management Practices (MTDNRC 2002) and the Montana Streamside Management Zone Rules when planning and implementing timber harvest operations.


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B. ASSUMPTIONS, METHODOLOGY, AND SCIENTIFIC ACCURACY OF INFORMATION USED

Water resource effects were identified as an analysis issue during scoping for this project. Potential effects include changes in water yield and subsequent increases in streamflow, increases in sediment production and transport to stream systems, and direct or indirect effects to channel, floodplain and wetland processes. The analysis areas for water resources are watersheds at the 6 HUC (hydrologic unit category) level. Six HUC watersheds are the standard analysis area used for most water resource cumulative effects analyses in Region 1 Forest Service. There are five – 6 HUC watersheds that surround the BCLMP area, ranging in size from 14,298 acres to 39,175 acres. Refer to Appendix A, Map 20, Sixth Level Watersheds Intersecting Project Boundary. Past and proposed activities within these five watersheds are summarized in Tables 3.4.1 through 3.4.4. Visual observations and topographic map interpretations were used to determine flow regimes, i.e., perennial versus intermittent or ephemeral, and relative channel conditions. Channels were not surveyed to determine Rosgen stream types. Stream type classification requires the presence of bankfull indicators. Bankfull indicators are generally not present along channels in the project area due to lack of significant annual bankfull flows and obliteration of bankfull features from livestock trampling and trailing. Representative photos of streams within the BCLMP area are available in the project file. The influence of vegetation treatments on water yield is typically measured by the degree of crown reduction in timber stands. Reductions in crown cover were estimated for past wildfire events, past and proposed vegetation treatments and proposed temporary road construction, and converted to an equivalent clear-cut area (ECA). Equivalent clear-cut area calculations reflect different harvest prescriptions that remove different levels of forest canopy. The results standardize these harvest areas to a percentage of an acre. For example, 10 acres of a 2-story harvest that removes 60 percent of the canopy is equal to 6 ECA acres, and 10 acres of commercial thinning that removes 40 percent of the canopy is equal to 2.5 ECA acres. Additionally, treatments that remove less than 17 percent of the overstory canopy have no effect on water yield. The relationship of percent canopy removal to ECA acre is nonlinear as presented in Forest Hydrology Part II (USDA 1973b). ECA calculations also account for recovery of timber stands based on the years since harvest/wildfire occurred. For this analysis, a moderate recovery curve was used which provides for 25% recovery of water yield by year four, 50% by year eight and 100% by year 45. Temporary roads were converted to ECA based on a 12-foot road prism. Past, proposed and cumulative ECA acres are displayed in Tables 3.4.2 through 3.4.4. Past timber harvest and wildfire acres on NFS land were generated through GIS for the five – 6 HUC watersheds that encompass the BCLMP area. ECA acres were then calculated based on the methodology described above. Past timber harvest and wildfire acres for other ownerships within the watersheds were estimated from visual review of 1996, 2005 and 2009 National Agriculture Imagery Program (NAIP) imagery provided through ArcMap and Google Earth. ECA acres for non-NFS land were also calculated, although the methodology differed slightly from that


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described above. Year of harvest/wildfire was not available for non-NFS land, so no recovery of water yield was accounted for, which results in a higher amount of ECA calculated. Additionally, actual crown removal by timber stand was not available, so the percent of timber stand removed over larger areas was estimated and converted to ECA. It is important to consider that these non-NFS lands are generally lower elevation landscapes that receive less precipitation, especially in the form of snow. A reduction in timber canopy within these lower elevation stands would have less influence on overall water yield within the watershed as compared to higher elevation stands were precipitation and snowfall is greater. Overall, the ECA acres for non-NFS land are more likely overestimated, than underestimated. Water yield increases from a reduction in timber canopy have been documented in forests throughout the west where deep snowpack and snowmelt runoff play a significant role in the overall hydrology of a watershed (Troendle 1983, Stednick 1996, and Bosch and Hewlett 1982). Documentation of water yield increases from low elevation watersheds across eastern Montana is limited. However, one source is Stednick (1996), which suggests that a 50 percent reduction in timber canopy is necessary to detect changes in annual water yield for the Central Plains region. Therefore, 50 percent or more of a 6HUC watershed in ECA condition is used as the threshold to evaluate effects of the proposed activities on water yield. Other water yield models, e.g., WATSED (Region 1 Forest Service Water and Sediment Yield Model), take the ECA analysis further by estimating changes to streamflow, including peak flow. However, these models require landscape specific runoff and erosion coefficients, neither of which have been developed for the CNF. Additionally, thresholds for increases in peak flow have not been developed for the CNF, in part due to the intermittent nature of the flow regimes that occur on the forest. Sediment yield in Region 1 Forest Service is typically estimated using the R1/R4 Guide for Predicting Sediment Yields from Forested Watersheds or adaptations of this model. This analysis however, does not utilize sediment yield models for a number of reasons. Natural surface erosion rates have not been validated for the CNF and management related erosion rates have not been developed for activities other than wildfire, road construction and harvest of green timber stands. Therefore, the model is not capable of adequately quantifying to a single cumulative value, the effects of other, non-timber management activities that are prevalent in the cumulative effects analysis area including recreation, grazing, and agricultural activities. The only way to address all of these activities cumulatively is to address each activity individually and then qualify, in general terms, the cumulative effects between specific activities where appropriate. Additionally, thresholds have not been developed for sediment yield increases on the CNF so any sediment model results can only be used for general alternative comparison. Finally, sediment models cannot provide precise quantification of erosion rates due to high degrees of error inherent in the modeling process. Elliot (2000) indicates that, at best, any predicted runoff or erosion value, by any model, will be within plus or minus 50 percent of the true value. For the purposes of this analysis, short-term is defined as five years or less, and long-term six years or more.


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II. AFFECTED ENVIRONMENT A. INTRODUCTION Both natural events and human activities have the potential to impact soil, water and riparian resources across forest and rangeland. The most significant potential natural events include wildfire and floods, while the most significant potential human activities include livestock grazing, agriculture, transportation systems, floodplain development and off road recreation. The degree of impact depends upon the magnitude of the event or activity, the soil and hydrologic characteristics of the watershed, and how sensitive and resilient these characteristics are to the disturbance. Soil and hydrologic characteristics vary extensively across landscapes and are dictated by local landform, geologic material and climate.

B. NATURAL CHARACTERISTICS AND PROCESSES Watersheds, undisturbed by human influences, are not static systems. Deep snow packs and heavy spring rains can cause flooding, landslides and instream erosion. Wildfire, wind, or insect and disease mortality can drastically alter the vegetative composition of a watershed. Depending on the extent of mortality and rate of stand decomposition, changes to the composition of vegetation can compound the natural processes of flooding, landslides and instream erosion. Beneficial uses, including aquatic habitat, can be negatively affected by these natural events. However, watersheds left undisturbed after natural events, can and do recover rapidly, and ultimately provide conditions that fully support all beneficial uses within a relatively short period of time (five years or less). These natural disturbances occur infrequently, which allows for recovery of hydrologic and erosional processes prior to the next major disturbance event. This results in pulse effects to water resources, which are generally moderate to high in magnitude, but low in frequency. Within the current climatic regime and prior to significant human influence, stream systems have developed under pulse type disturbances. C. GEOLOGY, LANDFORM, EROSION AND SEDIMENT The underlying geology within the BCLMP area is intermixed sedimentary beds of clay, silt, sand and coal. These mostly horizontal beds have weathered to form relatively steep topography along some ridgelines, while the remaining landscape is less steep and more convex in nature. Erosion is a natural process of geologic decomposition that occurs in all watersheds. The rate at which it occurs is a function of topography, soil and stream characteristics, precipitation and flow regimes, and vegetative cover. There are three basic types of erosion; 1) detachment and routing of individual soil particles from the land surface; 2) mass movement such as gravitational creep, slumps and landslides; and 3) detachment and mobilization of stream channel banks or bottom material, i.e., instream erosion. All of these processes produce sediment and all stream systems transport sediment. Sediment is a loosely used term that can refer to a wide range of substrate particle sizes, i.e., silt, sand, gravel, cobble, boulder, etc. The larger particle sizes are generally produced through instream erosion or mass wasting and are commonly referred to as bedload. The finer particles that are suspended in flowing water can be produced through all of the erosion processes mentioned above.


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The geology and landforms within the analysis area have produced soils that are generally stable and not highly erodible when adequately vegetated. MacDonald and Stednick (2003) suggest that undisturbed forested watersheds typically have very low erosion rates because of high infiltration rates and limited surface runoff. Summarized research concerning timber management in the Northern Rockies suggests that erosion rates for undisturbed forested landscapes (control watersheds, no harvest/roads) are very low (0 - 0.09 t/ac/yr, Stednick 2000). Therefore, in the absence of wildfire, hillslope surface erosion within undisturbed areas across the analysis area is considered to be nearly non-existent. The exception to this occurs on steep, high energy (south facing) landforms composed of fine textured material with high clay content. Due to dry site conditions and steep slopes, vegetation can be sparse on these landscapes. Episodic precipitation events that saturate these soils can result in mass soil slumping. However, these slumps generally do not move a significant distance downslope. At the broad scale across the BCLMP area, gravitational creep is considered the dominant erosion process under vegetated conditions, while surface and instream erosion are the dominant erosion processes after post-fire high intensity precipitation events. D. PRECIPITATION AND FLOW REGIMES Elevations across the analysis area range from 3400 to 4100 feet. Based on a 30-year period of record (1961-1990), the average annual precipitation associated with these elevations range from 14 to 18 inches (MSL-NRIS 2010). The majority of the precipitation falls as spring snow or rain from April through June. Climate, landform and vegetation characteristics result in ephemeral flow regimes for the majority of the drainage bottoms within the analysis area. These drainages are generally dry grassy swales or woody draws with extensive litter cover. Perennial stream systems of significant length are rare in the BCLMP area and where they occur, they have low discharge. They are either spring fed or are surface expressions of high water tables with very minimal flow. Defined channels are also rare because 1) flow regimes are generally insufficient to create bankfull features, 2) riparian vegetation, comprised mainly of sedge and rush species, is generally dense and obscures flow paths in most perennial systems, and 3) livestock trailing/trampling (current and historic) tends to obliterate natural channel features where they develop. The linear extent of perennial systems varies and is highly dependent on precipitation levels during preceding years. Known perennial systems occur within the headwaters of the West Fork of Little Pumpkin Creek below Whitetail Camp (SE sec 19, 0.4 mi.), Stacey Creek to the Forest boundary (SW sec 32, 0.6 mi.), upper West Fork Beaver Creek below spring (NW sec 14, SW sec 11, 1.1 mi.), an unnamed tributary to Beaver Creek (NW sec 14, 0.5 mi.), an unnamed tributary to Sheep Creek below spring 2 (NW sec 13, 0.1 mi.) and Sheep Creek below spring 1 (SW sec 18, sec 13, and SE sec 11, 1.9 mi.). Short perennial segments may also exist along Straight Creek. Active floodplains and wetlands not associated with the perennial stream systems are not known to exist within the project perimeter. Refer to Appendix A, Map 20 for locations of perennial streams. Representative photos of streams within the BCLMP area are available in the project file. Springs and seeps occur throughout the BCLMP area, many of which are linked to these perennial streams. Seventeen springs within the BCLMP area have been investigated by the


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Montana Bureau of Mines and Geology as part of a regional coal bed methane-monitoring network (Wheaton et al 2008). Their findings suggest all springs are recharged locally in shallow aquifers. These aquifers originate in either coal, sandstone or clinker layers. Water quality of these springs varies from sodium/bicarbonate dominated in the lower elevations to magnesium/sulfate dominated in the higher elevations. Coal bed methane occurs in deeper systems dominated by sodium/bicarbonate. Historically, beaver likely played a significant role in maintaining water resources throughout the BCLMP area through the development of extensive dam/pond structures. Although temporary, beaver dams and ponds are an important component of riparian systems for the functions and habitat they provide. These structures help regulate streamflow and sediment transport, and thereby temper the effects of fire and flood. They also help raise water tables, extend wetland areas and maintain late summer streamflow. Beaver populations have likely been reduced relative to historic levels. Although information on historical beaver populations does not exist for the BCLMP area, Wohl (2005) suggests that tens of millions of beaver were trapped in the western U.S. during the early to mid 1800’s. Trapping was so broad and intensive that most areas were “trapped out” within two decades. Assuming beaver were also prevalent historically in the Beaver Creek LMP area, the loss of beaver has likely resulted in 1) reduced water tables, wetland area, and late season streamflow, 2) increased frequency and magnitude of floods and sediment transport along most streams and 3) increased channel erosion. Vegetative composition is largely defined by climate and soils, but natural agents including fire, insects or disease, and wind can drastically alter vegetative cover. Over the last three decades, timber stands have been affected by wildfire on nearly 7,000 acres across the analysis area. Past wildfire events likely increased surface erosion and downslope sediment delivery. Surface erosion and sediment transport is generally highest immediately following the fire, but subsides quickly, relative to the recovery of ground vegetation (DeBano et al 1998. Insect and disease has been minimal across timber stands within the analysis area. However, snow loading during recent years (2007 – 2009) has resulted in timber damage throughout the BCLMP area, although mostly concentrated in higher density north aspect stands (Fuels Specialist Report in the Project Record). From a regional perspective, a combination of increased fuel loads and past fire suppression has likely resulted in stand conditions that have increased the potential for large crown fires compared to what occurred previous to European settlement, but similar to what has occurred over recent decades across the Western U.S. (Peterson et al 2005). Water yield (streamflow) from a watershed is the result of precipitation input (snow and rain) minus losses to evaporation, transpiration and seepage to regional aquifers. Transpiration loss from timber stands contributes to lower water yields. The combined effect of high density timber stands and the loss of beaver related hydrologic functions likely have contributed to the limited perennial flow regimes currently found in the analysis area. E. HUMAN INFLUENCES Human influences on water resources within the analysis areas include grazing, travel routes, timber harvest, fire suppression, and dispersed recreation. From a watershed and cumulative

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effects

perspective, additional activities occur on private land below the FS boundary that may affect water resources and include agriculture and floodplain development.

Livestock grazing on and below the Forest is widespread and therefore, potentially the main influence on water resources within the analysis area. Grazing has occurred for many decades and is expected to continue into the future. The perennial streams on NFS land receive some level of grazing pressure, but the total effect on water resources has not been fully documented. Although formal riparian surveys were not conducted for this project, field observations of streams in the BCLMP area suggest that they fall within the functional at-risk category, which means that an existing soil, hydrologic or vegetative attribute makes them susceptible to degradation

(USDI Bureau of Land Management 1998). Photo documentation of some streams is on file in the Project Record.

Additionally, the 2008 Montana Integrated 303(d)/305(b) Water Quality Report (MTDEQ 2008) indicates that grazing in riparian or shoreline zones is the source of impairment for 34 percent of the total impaired stream miles (37% of impaired segments) in the state. As noted previously, grazing is identified as a probable source of impairment for Otter Creek, an impaired stream that requires a TMDL. Probably causes related to this source are alterations in streamside vegetative cover and solids (suspended/bedload). Except for a small number of localized impacts, the existing transportation system within the BCLMP area has minimal influence on water quality. Most road segments are located along ridges or mid slopes, or are well vegetated with minimal vehicle use. Their location is of sufficient distance from most perennial streams to allow for dispersion of surface flow and deposition of sediment prior to reaching surface water. Exceptions include the following: Road 4769 is not properly drained and routes surface flow and sediment to Stacey Creek at the point where the road turns south and away from the mainstem channel in NESW section 32. Road 41338 crosses the perennial headwater mainstem of Sheep Creek below Spring #1. Although the culvert at this crossing appears functional, the crossing has very steep approaches and holds water as the roadbase is wet and rutted. There is potential for surface flow and sediment to be routed to Sheep Creek if the road is bladed and vehicle traffic increases. Impacts from recreation are mainly due to four wheel drive and OHV travel on native surface travel routes. There are 147 miles of road under FS jurisdiction in the analysis area. About 30 miles are needed for project activities. Fifteen miles of road and four miles of trail are currently open to public motorized use. Impacts are generally limited to crossings in wet draw bottoms or below spring/seep areas. Dispersed camping does occur, but is not common and effects to water resources have not been observed. Past vegetation management activities have occurred both within the BCLMP area and on adjacent state and private land. Timber stands have also been influenced by past wildfire events. On Forest Service land, 2,984 acres of timber harvest and thinning, and 5,084 acres of wildfire have occurred since 1950 with the majority occurring in 1988/89. Management on other public land (State) and on private land is mainly forage production for livestock. However, review of 1996, 2005, 2009 NAIP imagery suggests that timber harvest and crop production has also


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occurred in areas below the forest boundary in all watersheds. Timber harvest and wildfire on non-NFS land was estimated at over 20,000 acres. Timber harvest and wildfire acres have been estimated for the analysis area and summarized in the following table. Table 3.4.1: Existing Activities (Past And Present) By 6 HUC Watershed.

6 HUC Watershed (Refer to Appendix A, Map 20)

Existing Vegetation Treatment Acres¹

Existing Wildfire Acres¹

Existing Road Miles²

ID# Name Acres Percent NFS

Non NFS NFS Non

NFS NFS Non NFS NFS

100901020304 East Otter Creek

29,127 90 1,888 1,857 1,722 3,929 41 49

100901021102

Lower Little Pumpkin Creek

39,175 12 4,453 59 0 149 104 11

100901020603 Middle Beaver Creek

18,883 50 1,344 0 0 68 29 22

100901020601 Upper Beaver Creek

14,298 98 1,920 447 0 889 6 35

100901021101

Upper Little Pumpkin Creek

27,095 76 11,234 621 0 49 64 30

TOTAL 128,578 58 20,839 2,984 1,722 5,084 244 147 NOTE: The sum of acres/miles by watershed may not equal “TOTAL” value due to rounding factors. ¹Activity acres on National Forest System land from INFRA database and GIS. Activity acres on private land from review of 1996, 2005, 2009 NAIP imagery. ²Road miles from NFS and MTNRIS GIS databases. Most roads on or across private/state land are also accounted for. These past vegetation treatments, wildfire and roads have also been quantified cumulatively by estimating equivalent clear-cut area (ECA) acres, which are summarized in the following table. Refer to the next section – Effects of the Proposed Action alternative for a discussion of ECA calculations.


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Table 3.4.2: Existing ECA (Past And Present) By 6 HUC Watershed. Watershed (Refer to Appendix A, Map 20)

ECA Past and Present (does not include proposed activities)

Name Acres NFS harvest and wildfire acres

Non-NFS harvest and wildfire acres

Road acres Percent of watershed in ECA

East Otter Creek 29,127 697 2,548 173 12


39,175 24 2,634 223 7

Middle Beaver Creek 18,883 16 817 98 5

Upper Beaver Creek 14,298 192 701 80 7


27,095 56 6,921 182 26

TOTAL 128,578 984 13,621 757 12 NOTE: The sum of acres/miles by watershed may not equal “TOTAL” value due to rounding factors. The ECA estimates suggest that current activity levels in all watersheds are too low to cause measureable increases in water yield or streamflow. All watersheds are currently well below the 50 percent level that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains.

III. EFFECTS OF ALTERNATIVE A ON WATER RESOURCES – PROPOSED ACTION

A. DIRECT EFFECTS Construction of new stream crossings, i.e., bridges, culverts or fords, is the only action that is considered a direct effect to water resources. This is due to the immediate sediment delivery and flow disruption that generally occurs during installation. One new stream crossing would be required for a temporary road that crosses a perennial stream in SENW section 25 off rd 44236. Although the type of crossing is not known at this time, it would meet the requirements of a MT-DFWP 124 permit and would be in place only for the duration of the harvest activities, and reclaimed and revegetated after use. Localized alteration to the channel at the crossing site would occur for the duration of the structures use, while increases in sediment delivery to the channel would occur during installation and removal of the structure. Impacts to water quality and adjacent riparian area would be short term (1-2 yrs) as the crossing site would recover rapidly after removal.


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B. INDIRECT EFFECTS In contrast to direct effects, indirect effects occur at a later time and/or distance from the activity. Indirect effects concerning water resources generally result from changes in soil and hydrologic processes, i.e., increases in either water or sediment yield across a landscape and the subsequent effects of these increases on channel, floodplain and wetland functions and habitats.

Water Yield As suggested in Forest Hydrology Part II (USDA 1973b), treatments that remove less than 17 percent of the overstory canopy of a timber stand have no effect on water yield. Proposed treatments that fall into this category include NC2, NC3, PCT, SCNC and STR1. Similar proposed treatments, when combined with slightly higher overstory mortality during prescribed burning may exceed 17 percent, but remain at or below 20 percent total canopy removal. Twenty percent canopy removal results in minimal ECA acres. Proposed treatments that fall into this category include NC4, NC5, NC1, SC, and STR. Prescribed burning treatment (RXB) is also expected to result in little to no reduction in canopy cover. DeBano et al (1998) suggest that the effect of prescribed burning alone on streamflow is almost non-existent under low severity burns. This is consistent with the rationale above that 17% level of canopy removal from timber harvest is too low to have an effect on water yield. Treatments with the highest level of total canopy removal (with fuel treatment burning) include CT (70%), CT1 (50%), LIB (85%), SH1 (70%) and ST1 (95%). Where the combination of harvest/thinning and burning exceeds 17 percent canopy removal of the stand, ECA acres are generated and displayed in Table 3.4.3. The watershed area affected by the proposed activities as summarized by the ECA analysis is two percent or less for all watersheds under this alternative. This is well below the 50 percent level that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Therefore, the influence of the proposed vegetation management activities on water yield is not expected to be measurable and would result in a very low risk of affecting channel, floodplain or wetland processes, and water quantity and quality within the project area. .


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Table 3.4.3: Proposed Treatment Acres and Estimated ECA Acres by Alternative. Watershed (Refer to Appendix A, Map 20)

Proposed Activities (Does not include past/present activities)

Name Acres

Vegetation Treatment Acres

Vegetation Treatment ECA Acres

Temporary Road ECA Acres¹

Percent of Watershed in ECA Condition

Alt A Alt B Alt C Alt A Alt B Alt C Alt A Alt B Alt C Alt A Alt B Alt C

East Fork Otter Creek

29,127 1,464 1,464 961 404 404 165 6 6 2 1 1 <1


39,175 822 822 822 311 246 246 4 3 3 <1 <1 <1

Middle Beaver Creek

18,883 1,408 1,408 1,263 260 246 166 2 2 2 1 1 <1

Upper Beaver Creek

14,298 5,085 5,085 4,573 355 280 171 4 3 1 2 2 1


27,095 1,727 1,727 440 380 374 96 10 8 1 1 1 <1

Total 128,578 10,508 10,508 8,059 1,710 1,550 844 27 22 8 1 1 <1 NOTE: The sum of acres/miles by watershed may not equal “TOTAL” value due to rounding factors. ¹Temporary road miles were converted to ECA acres based on a 12-foot road prism.


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Sediment Yield The proposed management activities have the potential to increase upslope sediment production and downslope sediment transport to watercourses. The level of risk is a function of the degree of soil disturbance, slope, slope distance and slope filter capacity. From a qualitative perspective, the 18.2 miles of proposed new temporary road construction would result in the greatest degree of soil disturbance, relative to all other proposed activities. However, road locations are generally along ridge tops or upper slopes, which would provide adequate, filter distance between the road and the nearest watercourse downslope. Additionally, the nearest watercourses are, for the most part, ephemeral or intermittent which further reduces the risk of sediment transport to perennial systems. New temporary roads would be closed and obliterated after project implementation using a variety of methods including scarifying/ripping, seeding, signing, obstructing (with slash) and recontouring. Because these roads would be rehabilitated, sediment production and transport would be short-term, less than five years. Seven short road segments totaling approximately 2.1 miles would be obliterated during or after treatment activities cease. These actions would reduce road densities within the Upper Beaver and Little Pumpkin Creek watersheds, thereby reducing the risk of cumulative watershed effects over the long-term. Short-term effects may involve new soil disturbance from ripping compacted road segments where necessary, but stabilization should occur soon after as these areas revegetate. Vegetation treatments also have the potential to disturb soils and route sediment downslope, but only for those treatments that utilize machinery. Of the commercial treatments, approximately 1,762 acres would be tractor yarded. Of the non-commercial treatments, low ground pressure machinery could be used on 2,102 acres on slopes less than 30 percent. Following standard BMPs (refer to Appendix C), long-term soil disturbance and transport relative to frequency and location of skid trails and landings, would be minimized. This includes BMPs that recommends skid trails and landings not be located in the bottom of draws. In combination with low ground pressure machinery, risk of erosion and downslope sediment delivery to watercourses would be low from these vegetation treatments. Non-commercial thinning treatments that would not utilize machinery are proposed on 2,118 acres. Hand felling and piling in these treatments is not expected to result in any measurable ground disturbance, except for small areas where hand piles are burned. Similarly, prescribed burning is proposed on 3,594 acres and involves mainly non-forested vegetation types where fuel loads are relatively low. Burning would occur in one treatment under this alternative. This burning is expected to result in minor consumption of the duff layer and only scattered exposure of surface soils where fuels were concentrated. Overall, fire severity on soils is expected to be low. Fire intensity within riparian areas or woody draws is also expected to be low due to special design features that prohibit fire ignition within these areas. Both non-mechanical treatments and prescribed burning would result in low risk of on-site erosion, sediment delivery and downslope effects to watercourses. Approximately 3,545 acres in the project area would not be treated. Although on-site sediment production is anticipated from some activities, the majority of this sediment would be deposited and stabilized on hillslopes below the activity and likely not reach perennial streams within the BCLMP area. Adhering to SMZ regulations and BMP’s would help


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minimize sediment production and reduce sediment transport to drainage bottoms. According to The Montana 2008 Forestry BMP Audit Report (MT DNRC 2008), 96% of the BMP practices rated on Federal lands were effective in protecting soil and water resources, while 91% of the “high risk” BMP’s (road drainage practices near streams) rated on Federal lands were also effective. The effects of temporary road construction, maintenance, obliteration, and skidding operations would be short-term as roads and skid trails stabilize and revegetate after closure. Overall the risk of sediment delivery to perennial streams is very low. Approximately 20.1 miles of existing system road (maintenance level 2 and 3) would be reconstructed or brought up to maintenance standards (BMP implementation) to facilitate log hauling. These actions would improve road drainage features and reduce the risk of sediment generation and delivery to watercourses. The actions would address the specific route issues previously identified for routes 4769 and 41338. Refer to Section II: Affected Environment, E. Human Influences. Approximately 9.3 miles of existing system road (maintenance level 1) and trail would receive maintenance to facilitate log hauling. Currently, the majority of these roads are well vegetated and in most cases hydrologically benign. Maintenance of these vegetated roads to facilitate hauling will require removal of encroached conifers, and/or blading to level rutting that would result from log trucks. In the short-term, these routes would have similar effects as the newly constructed temporary roads. These roads would be closed to public use after project implementation, but not obliterated as with temporary roads. Adequate long-term drainage would be installed, and surfaces would be ripped and seeded as necessary to ensure rapid revegetation.

Channel, Floodplain, Spring and Wetland Functions As discussed previously, perennial stream courses are rare, disconnected and of limited length within the BCLMP area. However, short, localized riparian systems do exist and do support wetland plants and associated habitat. The risk of sediment delivery to these systems is low due to adequate filter distances (50 feet or more) and implementation of SMZ regulations and BMP’s. Per SMZ regulations, equipment operation can occur no closer than 50 feet from streams on slopes under 35 percent and 100 feet on slopes greater than 35 percent. The risk of affecting floodplain, spring or riparian wetland function is low because the activities are not expected to substantially influence hillslope or channel hydrology, or sediment production and transport. Proposed yarding activities across perennial or intermittent stream courses would require prior approval through the SMZ alternative practice provisions and approval would only be granted when the design of the yarding activities is shown to maintain SMZ functions. Therefore, long-term indirect effects to localized channel and floodplain function, or wetland habitat are not anticipated. C. CUMULATIVE EFFECTS Cumulative vegetation treatments and wildfire have been quantified by estimating ECA acres for past, present, reasonably foreseeable, and proposed activities on NFS and non-NFS land and are displayed below in Table 3.4.4. The only reasonably foreseeable activities with potential to affect


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ECA calculations within the analysis area are those proposed under this project. Ongoing vegetation treatments on NFS land have already been accounted for in the existing ECA calculations and future activities on private land cannot be adequately quantified. ECA road acres include all roads within the watershed and are based on the best available GIS data. The cumulative ECA estimates suggest that activity levels in all watersheds would be too low to cause measurable increases in water yield. All watersheds are 28 percent or less and well under the 50 percent threshold that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Therefore, the influence of the proposed vegetation management activities on water yield is not expected to be measurable and would result in a very low risk of affecting channel, floodplain or wetland processes, and water quantity and quality downstream from the project area. Livestock grazing on and below the Forest, along with crop production on private lands are widespread, but generally concentrated along valley bottoms. Therefore, these activities are potentially the major influence on water resources within the Beaver, Little Pumpkin and East Otter Creek watersheds. These activities have occurred for many decades in the past and are expected to continue well into the future. On NFS land, timber stand density would decrease thereby improving livestock grazing distribution, which generally results in less grazing pressure/impact along perennial streams and wet meadows. Future natural disturbance events (fire followed by flood) would likely be the most detrimental to water resources from a pulse disturbance perspective. These events are expected to occur again and could be severe given current vegetative conditions and anticipated regional climate change. Fire suppression has allowed the excessive growth of all age classes of timber. High density stands combined with the recent snow load damage has resulted in excessive ground and ladder fuels; especially in north aspect stands (see Fuels Specialist Report in Project Record). From a regional perspective, these types of conditions increase the risk for stand replacement wildfires to occur that may be larger and of higher intensity than what occurred prior to European settlement Peterson et al 2005). Compounding this risk further is the anticipated increase in temperature due to climate change. Climate change research suggests that summer temperatures are expected to continue to increase for Western North America (Running 2006) and specifically for the northern Great Plains (USGCRP 2009). Westerling et al (2006) found that increasing spring and summer temperatures over the last three decades has resulted in more frequent and longer duration large wildfires in the western U.S., and specifically in the Northern Rockies. McKensie et al (2004) suggests that the amount of area burned annually in western states will increase dramatically with increasing summer temperatures. Their research suggests that fire seasons in Montana, Wyoming and New Mexico, in particular, are acutely sensitive to summer temperatures and climate change. Refer to Section II: Affected Environment for a discussion of wildfire effects on water resources.


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Table 3.4.4: Cumulative ECA Acres – Past, Present and Proposed Activities. Watershed (Refer to Appendix A, Map 20) ECA – All ownerships

Name Acres

Vegetation treatment and wildfire ECA acres Road ECA Acres¹ Percent of Watershed in ECA

Condition

Alt A Alt B Alt C Alt A Alt B Alt C Alt A Alt B Alt C

East Fork Otter Creek 29,127 3823 3823 3583 180 179 176 13 13 12

Lower Little Pumpkin Creek 39,175 3192 3127 3127 227 226 226 8 8 8

Middle Beaver Creek 18,883 1190 1176 1097 100 100 100 6 6 6

Upper Beaver Creek 14,298 1328 1253 1144 85 84 81 9 9 8

Upper Little Pumpkin Creek 27,095 7539 7532 7255 192 190 183 28 28 27

Total 128,578 17,072 16,912 16,206 784 779 765 13 13 13 NOTE: The sum of acres/miles by watershed may not equal “TOTAL” value due to rounding factors. ¹Temporary road miles were converted to ECA acres based on a 12-foot road width, existing roads based on a 16-foot road width.


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The proposed vegetation treatments incorporate recommendations by Peterson et al (2005) for effective fuels management. The treatments would reduce timber stand density and ground, ladder and crown fuel loads, and therefore reduce the risk for stand replacement wildfire (see Fuels Specialist Report). The risk of impact to soil and hydrologic functions from stand replacement wildfire would be reduced compared to the no action alternative, but would not be totally eliminated. Accelerated soil erosion is still likely, depending on fire intensity and area burned. Soil erosion would be more localized and mosaic across the landscape than under the no action alternative. Channel adjustments from overland flow and sedimentation would still be expected, but again more localized than no action. These effects could still reach perennial stream segments on and off forest, but only through post-fire high intensity rain events. Previous wildfires on the district have also produced post-fire landscape responses; Ft Howes and Tobin Fire (Nienow 2002, USDA 2000a and 2000b), Watt Draw Fire (USDA 2006b). Stream systems would stabilize as vegetative recovery occurs during post-fire years and the recovery period should be more rapid than no treatment due to overall lower burn intensity and severity. Cumulatively, existing roads and grazing would compound the effects of post-fire precipitation events, but to a lesser degree than no treatment. Roads would increase surface and subsurface drainage efficiency, routing upslope waters to natural channels at higher rates, thereby increasing floodwater levels. Roads that restrict floodwater access to floodplains would also result in higher flood stage. Concentrated livestock trampling and trailing along watercourses can also increase drainage efficiency and destabilize stream banks. The combination of these conditions would increase the risk of more flood damage to streams and downstream human developments following a wildfire. The effects are expected to be highest in those drainages or subdrainages that burn with high intensity over a large area, and where road and livestock densities are high. Of the 18.2 miles of new temporary roads, approximately seven miles would be constructed along lower slopes adjacent to the bottom of draws, which could increase the risk of affecting water resources, even though the roads would be temporary and the draws may be ephemeral. This is primarily a cumulative effects issue where these roads could compound the effects of post wildfire flood events. The following temporary roads are located on lower slopes or within valley bottoms and adjacent to intermittent or ephemeral channels: 02, 03, 05, 06, 07, 08, 10, 11, 31, 32, 35, 42, 48, 50, 53, 54, 58, 59 and 63. BMP’s and project design criteria would ensure these roads are not located in the absolute bottom of draws, which would reduce the potential for concentrated runoff in the draws from intersecting road surfaces. The risk is short-term assuming adequate and rapid rehabilitation. The risk of cumulative effects to water quality, water quantity and channel/floodplain/wetland functions are low due to proposed project activities, design features, and BMP implementation.


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IV. EFFECTS OF ALTERNATIVE B ON WATER RESOURCES – PREFERRED ALTERNATIVE

A. DIRECT EFFECTS One new stream crossing would be required for a temporary road that crosses a perennial stream in SENW section 25 off rd 44236. Although the type of crossing is not known at this time, it would meet the requirements of a MT-DFWP 124 permit and would be in place only for the duration of the harvest activities, and reclaimed and revegetated after use. Localized alteration to the channel at the crossing site would occur for the duration of the structures use, while increases in sediment delivery to the channel would occur during installation and removal of the structure. Impacts to water quality and adjacent riparian area would be short term (1-2 yrs) as the crossing site would recover rapidly after removal. B. INDIRECT EFFECTS Water Yield As suggested in Forest Hydrology Part II (USDA 1973b), treatments that remove less than 17 percent of the overstory canopy of a timber stand have no effect on water yield. Proposed treatments that fall into this category include NC2, NC3, PCT, SCNC and STR1. Similar proposed treatments, when combined with slightly higher overstory mortality during prescribed burning may exceed 17 percent, but remain at or below 20 percent total canopy removal. Twenty percent canopy removal results in minimal ECA acres. Proposed treatments that fall into this category include NC4, NC5, NC1, SC, and STR. Prescribed burning treatment (RXB) is also expected to result in little to no reduction in canopy cover. DeBano et al (1998) suggest that the effect of prescribed burning alone on streamflow is almost non-existent under low severity burns. This is consistent with the rationale above that 17% level of canopy removal from timber harvest is too low to have an effect on water yield. Treatments with the highest level of total canopy removal (with fuel treatment burning) include CT (70%), CT1 (50%), LIB (85%), SH1 (70%) and ST1 (95%). Where the combination of harvest/thinning and burning exceeds 17 percent canopy removal of the stand, ECA acres are generated and displayed in Table 3.4.3. The watershed area affected by the proposed activities as summarized by the ECA analysis is two percent or less for all watersheds under this alternative. This is well below the 50 percent level that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Therefore, the influence of the proposed vegetation management activities on water yield is not expected to be measurable and would result in a very low risk of affecting channel, floodplain or wetland processes, and water quantity and quality within the project area.

Sediment Yield The proposed management activities have the potential to increase upslope sediment production and downslope sediment transport to watercourses. The level of risk is a function of the degree of soil disturbance, slope, slope distance and slope filter capacity. From a qualitative perspective, the 15.2 miles of proposed new temporary road construction would result in the greatest degree


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of soil disturbance, relative to all other proposed activities. However, road locations are generally along ridge tops or upper slopes, which would provide adequate, filter distance between the road and the nearest watercourse downslope. Additionally, the nearest watercourses are, for the most part, ephemeral or intermittent which further reduces the risk of sediment transport to perennial systems. New temporary roads would be closed and obliterated after project implementation using a variety of methods including scarifying/ripping, seeding, signing, obstructing (with slash) and recontouring. Because these roads would be rehabilitated, sediment production and transport would be short-term, less than five years. Seven short road segments totaling approximately 2.1 miles would be obliterated during or after treatment activities cease. These actions would reduce road densities within the Upper Beaver and Little Pumpkin Creek watersheds, thereby reducing the risk of cumulative watershed effects over the long-term. Short-term effects may involve new soil disturbance from ripping compacted road segments where necessary, but stabilization should occur soon after as these areas revegetate. Vegetation treatments also have the potential to disturb soils and route sediment downslope, but only for those treatments that utilize machinery. Of the commercial treatments, approximately 1,762 acres would be tractor yarded. Of the non-commercial treatments, low ground pressure machinery could be used on 2,187 acres on slopes less than 30 percent. Following standard BMPs (refer to Appendix C), long-term soil disturbance and transport relative to frequency and location of skid trails and landings, would be minimized. This includes BMPs, which recommend that skid trails and landings not be located in the bottom of draws. In combination with low ground pressure machinery, risk of erosion and downslope sediment delivery to watercourses would be low from these vegetation treatments. Non-commercial thinning treatments that would not utilize machinery are proposed on 2,241 acres. Hand felling and piling in these treatments is not expected to result in any measurable ground disturbance, except for small areas where hand piles are burned. Similarly, prescribed burning is proposed on 3,594 acres and involves mainly non-forested vegetation types where fuel loads are relatively low. Burning may occur in up to two treatments (10-15 years apart) under this alternative. This burning is expected to result in minor consumption of the duff layer and only scattered exposure of surface soils where fuels were concentrated. Overall, fire severity on soils is expected to be low. Fire intensity within riparian areas or woody draws is also expected to be low due to special design features that prohibit fire ignition within these areas. Both non-mechanical treatments and prescribed burning would result in low risk of on-site erosion, sediment delivery and downslope effects to watercourses. Approximately 3,545 acres in the project area would not be treated. Although on-site sediment production is anticipated from some activities, the majority of this sediment would be deposited and stabilized on hillslopes below the activity and likely not reach perennial streams within the BCLMP area. Adhering to SMZ regulations and BMP’s would help minimize sediment production and reduce sediment transport to drainage bottoms. According to The Montana 2008 Forestry BMP Audit Report (MT DNRC 2008), 96% of the BMP practices rated on Federal lands were effective in protecting soil and water resources, while 91% of the “high risk” BMP’s (road drainage practices near streams) rated on Federal lands were also


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effective. The effects of temporary road construction, maintenance, obliteration, and skidding operations would be short-term as roads and skid trails stabilize and revegetate after closure. Overall the risk of sediment delivery to perennial streams is very low. Approximately 21.1 miles of existing system road (maintenance level 2 and 3) would be reconstructed or brought up to maintenance standards (BMP implementation) to facilitate log hauling. These actions would improve road drainage features and reduce the risk of sediment generation and delivery to watercourses. The actions would address the specific route issues previously identified for routes 4769 and 41338. Refer to Section II: Affected Environment, E. Human Influences. Approximately 5.9 miles of existing system road (maintenance level 1) and trail would receive maintenance to facilitate log hauling. Currently, the majority of these roads are well vegetated and in most cases hydrologically benign. Maintenance of these vegetated roads to facilitate hauling will require removal of encroached conifers, and/or blading to level rutting that would result from log trucks. In the short-term, these routes would have similar effects as the newly constructed temporary roads. These roads would be closed to public use after project implementation, but not obliterated as with temporary roads. Adequate long-term drainage would be installed, and surfaces would be ripped and seeded as necessary to ensure rapid revegetation.

Channel, Floodplain, Spring and Wetland Functions As discussed previously, perennial stream courses are rare, disconnected and of limited length within the BCLMP area. However, short, localized riparian systems do exist and do support wetland plants and associated habitat. The risk of sediment delivery to these systems is low due to adequate filter distances (50 feet or more) and implementation of SMZ regulations and BMP’s. Per SMZ regulations, equipment operation can occur no closer than 50 feet from streams on slopes under 35 percent and 100 feet on slopes greater than 35 percent. The risk of affecting floodplain, spring or riparian wetland function is low because the activities are not expected to substantially influence hillslope or channel hydrology, or sediment production and transport. Proposed yarding activities across perennial or intermittent stream courses would require prior approval through the SMZ alternative practice provisions and approval would only be granted when the design of the yarding activities is shown to maintain SMZ functions. Therefore, long-term indirect effects to localized channel and floodplain function, or wetland habitat are not anticipated. C. CUMULATIVE EFFECTS Cumulative vegetation treatments and wildfire have been quantified by estimating ECA acres for past, present, reasonably foreseeable, and proposed activities on NFS and non-NFS land and are displayed below in Table 3.4.4. The only reasonably foreseeable activities with potential to affect ECA calculations within the analysis area are those proposed under this project. Ongoing vegetation treatments on NFS land have already been accounted for in the existing ECA calculations and future activities on private land cannot be adequately quantified. ECA road acres include all roads within the watershed and are based on the best available GIS data.


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The cumulative ECA estimates suggest that activity levels in all watersheds would be too low to cause measurable increases in water yield or streamflows. All watersheds are 28 percent or less and well under the 50 percent threshold that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Livestock grazing on and below the Forest, along with crop production on private lands are widespread, but generally concentrated along valley bottoms. Therefore, these activities are potentially the major influence on water resources within the Beaver, Little Pumpkin and East Otter Creek watersheds. These activities have occurred for many decades in the past and are expected to continue well into the future. On NFS land, timber stand density would decrease thereby improving livestock grazing distribution, which generally results in less grazing pressure/impact along perennial streams and wet meadows. Future natural disturbance events (fire followed by flood) would likely be the most detrimental to water resources from a pulse disturbance perspective. These events are expected to occur again and could be severe given current vegetative conditions and anticipated regional climate change. Fire suppression has allowed the excessive growth of all age classes of timber. High density stands combined with the recent snow load damage has resulted in excessive ground and ladder fuels; especially in north aspect stands (see Fuels Specialist Report in Project Record). From a regional perspective, these types of conditions increase the risk for stand replacement wildfires to occur that may be larger and of higher intensity than what occurred prior to European settlement Peterson et al 2005). Compounding this risk further is the anticipated increase in temperature due to climate change. Climate change research suggests that summer temperatures are expected to continue to increase for Western North America (Running 2006) and specifically for the northern Great Plains (USGCRP 2009). Westerling et al (2006) found that increasing spring and summer temperatures over the last three decades has resulted in more frequent and longer duration large wildfires in the western U.S., and specifically in the Northern Rockies. McKensie et al (2004) suggests that the amount of area burned annually in western states will increase dramatically with increasing summer temperatures. Their research suggests that fire seasons in Montana, Wyoming and New Mexico, in particular, are acutely sensitive to summer temperatures and climate change. Refer to Section II: Affected Environment for a discussion of wildfire effects on water resources. The proposed vegetation treatments incorporate recommendations by Peterson et al (2005) for effective fuels management. The treatments would reduce timber stand density and ground, ladder and crown fuel loads, and therefore reduce the risk for stand replacement wildfire (see Fuels Specialist Report). The risk of impact to soil and hydrologic functions from stand replacement wildfire would be reduced compared to the no action alternative, but would not be totally eliminated. Accelerated soil erosion is still likely, depending on fire intensity and area burned. Soil erosion would be more localized and mosaic across the landscape than under the no action alternative. Channel adjustments from overland flow and sedimentation would still be expected, but again more localized than no action. These effects could still reach perennial stream segments on and off forest, but only through post-fire high intensity rain events. Previous wildfires on the district have also produced post-fire landscape responses; Ft Howes and Tobin Fire (Nienow 2002, USDA 2000a and 2000b), Watt Draw Fire (USDA 2006b). Stream systems


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would stabilize as vegetative recovery occurs during post-fire years and the recovery period should be more rapid than no treatment due to overall lower burn intensity and severity. Cumulatively, existing roads and grazing would compound the effects of post-fire precipitation events, but to a lesser degree than no treatment. Roads would increase surface and subsurface drainage efficiency, routing upslope waters to natural channels at higher rates, thereby increasing floodwater levels. Roads that restrict floodwater access to floodplains would also result in higher flood stage. Concentrated livestock trampling and trailing along watercourses can also increase drainage efficiency and destabilize stream banks. The combination of these conditions would increase the risk of more flood damage to streams and downstream human developments following a wildfire. The effects are expected to be highest in those drainages or subdrainages that burn with high intensity over a large area, and where road and livestock densities are high. Of the total 15.2 miles of new temporary roads, approximately five miles would be constructed along lower slopes adjacent to the bottom of draws, which could increase the risk of affecting water resources, even though the roads would be temporary and the draws may be ephemeral. This is primarily a cumulative effects issue where these roads could compound the effects of post wildfire flood events. The following temporary roads are located on lower slopes or within valley bottoms and adjacent to intermittent or ephemeral channels: 02, 03, 05, 06, 08, 31, 32, 35, 48, 50, 53, 58, 59 and 63. BMP’s and project design criteria would ensure these roads are not located in the absolute bottom of draws, which would reduce the potential for concentrated runoff in the draws from intersecting road surfaces. The risk is short-term assuming adequate and rapid rehabilitation. The risk of cumulative effects to water quality, water quantity and channel/floodplain/wetland functions are low due to proposed project activities, design features, and BMP implementation.

V. EFFECTS OF ALTERNATIVE C ON WATER RESOURCES

A. DIRECT EFFECTS No new stream crossings are proposed under this alternative, therefore there are no direct effects. B. INDIRECT EFFECTS Water Yield As suggested in Forest Hydrology Part II (USDA 1973b), treatments that remove less than 17 percent of the overstory canopy of a timber stand have no effect on water yield. Proposed treatments that fall into this category include NC2, NC3 and SCNC. Similar proposed treatments, when combined with slightly higher overstory mortality during prescribed burning may exceed 17 percent, but remain at or below 20 percent total canopy removal. Twenty percent canopy removal results in minimal ECA acres. Proposed treatments that fall into this category include NC4, NC5, NC1, SC, and STR. Prescribed burning treatment (RXB) is also expected to result in


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little to no reduction in canopy cover. DeBano et al (1998) suggest that the effect of prescribed burning alone on streamflow is almost non-existent under low severity burns. This is consistent with the rationale above that 17% level of canopy removal from timber harvest is too low to have an effect on water yield. Treatments with the highest level of total canopy removal (with fuel treatment burning) include CT (70%), LIB (85%), SH1 (70%) and ST1 (95%). Where the combination of harvest/thinning and burning exceeds 17 percent canopy removal of the stand, ECA acres are generated and displayed in Table 3.4.3. The watershed area affected by the proposed activities as summarized by the ECA analysis is two percent or less for all watersheds under this alternative. This is well below the 50 percent level that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Therefore, the influence of the proposed vegetation management activities on water yield is not expected to be measurable and would result in a very low risk of affecting channel, floodplain or wetland processes, and water quantity and quality within the project area.

Sediment Yield The proposed management activities have the potential to increase upslope sediment production and downslope sediment transport to watercourses. The level of risk is a function of the degree of soil disturbance, slope, slope distance and slope filter capacity. From a qualitative perspective, the 5.7 miles of proposed new temporary road construction would result in the greatest degree of soil disturbance, relative to all other proposed activities. However, road locations are generally along ridge tops or upper slopes, which would provide adequate, filter distance between the road and the nearest watercourse downslope. Additionally, the nearest watercourses are, for the most part, ephemeral or intermittent which further reduces the risk of sediment transport to perennial systems. New temporary roads would be closed and obliterated after project implementation using a variety of methods including scarifying/ripping, seeding, signing, obstructing (with slash) and recontouring. Because these roads would be rehabilitated, sediment production and transport would be short-term, less than five years. Refer to individual action alternatives for specific effects of temporary road construction. Refer to individual action alternatives for specific effects of maintenance or reconstruction of existing roads. Seven short road segments totaling approximately 2.1 miles would be obliterated during or after treatment activities cease. These actions would reduce road densities within the Upper Beaver and Little Pumpkin Creek watersheds, thereby reducing the risk of cumulative watershed effects over the long-term. Short-term effects may involve new soil disturbance from ripping compacted road segments where necessary, but stabilization should occur soon after as these areas revegetate. Vegetation treatments also have the potential to disturb soils and route sediment downslope, but only for those treatments that utilize machinery. Of the commercial treatments, approximately 756 acres would be tractor yarded. Of the non-commercial treatments, low ground pressure machinery could be used on 1,850 acres on slopes less than 30 percent. Following standard BMPs, long-term soil disturbance and transport relative to frequency and location of skid trails and landings, would be minimized. This includes BMPs, which recommend that skid trails and


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landings not be located in the bottom of draws. In combination with low ground pressure machinery, risk of erosion and downslope sediment delivery to watercourses would be low from these vegetation treatments. Non-commercial thinning treatments that would not utilize machinery are proposed on 1,767 acres. Hand felling and piling in these treatments is not expected to result in any measurable ground disturbance, except for small areas where hand piles are burned. Similarly, prescribed burning is proposed on 3,506 acres and involves mainly non-forested vegetation types where fuel loads are relatively low. Burning may occur in up to two treatments (10-15 years apart) under this alternative. This burning is expected to result in minor consumption of the duff layer and only scattered exposure of surface soils where fuels were concentrated. Overall, fire severity on soils is expected to be low. Fire intensity within riparian areas or woody draws is also expected to be low due to special design features that prohibit fire ignition within these areas. Both non-mechanical treatments and prescribed burning would result in low risk of on-site erosion, sediment delivery and downslope effects to watercourses. Approximately 5,994 acres in the project area would not be treated. Although on-site sediment production is anticipated from some activities, the majority of this sediment would be deposited and stabilized on hillslopes below the activity and likely not reach perennial streams within the BCLMP area. Adhering to SMZ regulations and BMP’s would help minimize sediment production and reduce sediment transport to drainage bottoms. According to The Montana 2008 Forestry BMP Audit Report (MT DNRC 2008), 96% of the BMP practices rated on Federal lands were effective in protecting soil and water resources, while 91% of the “high risk” BMP’s (road drainage practices near streams) rated on Federal lands were also effective. The effects of temporary road construction, maintenance, obliteration, and skidding operations would be short-term as roads and skid trails stabilize and revegetate after closure. Overall the risk of sediment delivery to perennial streams is very low. Approximately 13.8 miles of existing system road (maintenance level 2 and 3) would be reconstructed or brought up to maintenance standards (BMP implementation) to facilitate log hauling. These actions would improve road drainage features and reduce the risk of sediment generation and delivery to watercourses. The actions would address the specific route issues previously identified for routes 4769 and 41338. Refer to Section II: Affected Environment, E. Human Influences. Approximately 3.1 miles of existing system road (maintenance level 1) and trail would receive maintenance to facilitate log hauling. Currently, the majority of these roads are well vegetated and in most cases hydrologically benign. Maintenance of these vegetated roads to facilitate hauling will require removal of encroached conifers, and/or blading to level rutting that would result from log trucks. In the short-term, these routes would have similar effects as the newly constructed temporary roads. These roads would be closed to public use after project implementation, but not obliterated as with temporary roads. Adequate long-term drainage would be installed, and surfaces would be ripped and seeded as necessary to ensure rapid revegetation.


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Channel, Floodplain, Spring and Wetland Functions As discussed previously, perennial stream courses are rare, disconnected and of limited length within the BCLMP area. However, short, localized riparian systems do exist and do support wetland plants and associated habitat. The risk of sediment delivery to these systems is low due to adequate filter distances (50 feet or more) and implementation of SMZ regulations and BMP’s. Per SMZ regulations, equipment operation can occur no closer than 50 feet from streams on slopes under 35 percent and 100 feet on slopes greater than 35 percent. The risk of affecting floodplain, spring or riparian wetland function is low because the activities are not expected to substantially influence hillslope or channel hydrology, or sediment production and transport. Proposed yarding activities across perennial or intermittent stream courses would require prior approval through the SMZ alternative practice provisions and approval would only be granted when the design of the yarding activities is shown to maintain SMZ functions. Therefore, long-term indirect effects to localized channel and floodplain function, or wetland habitat are not anticipated. C. CUMULATIVE EFFECTS Cumulative vegetation treatments and wildfire have been quantified by estimating ECA acres for past, present, reasonably foreseeable, and proposed activities on NFS and non-NFS land and are displayed below in Table 3.4.4. The only reasonably foreseeable activities with potential to affect ECA calculations within the analysis area are those proposed under this project. Ongoing vegetation treatments on NFS land have already been accounted for in the existing ECA calculations and future activities on private land cannot be adequately quantified. ECA road acres include all roads within the watershed and are based on the best available GIS data. The cumulative ECA estimates suggest that activity levels in all watersheds would be too low to cause measurable increases in water yield or streamflows. All watersheds are 28 percent or less and well under the 50 percent threshold that Stednick (1996) suggests may be sufficient to detect changes in annual water yield for the Central Plains. Livestock grazing on and below the Forest, along with crop production on private lands are widespread, but generally concentrated along valley bottoms. Therefore, these activities are potentially the major influence on water resources within the Beaver, Little Pumpkin and East Otter Creek watersheds. These activities have occurred for many decades in the past and are expected to continue well into the future. On NFS land, timber stand density would decrease thereby improving livestock grazing distribution, which generally results in less grazing pressure/impact along perennial streams and wet meadows. Future natural disturbance events (fire followed by flood) would likely be the most detrimental to water resources from a pulse disturbance perspective. These events are expected to occur again and could be severe given current vegetative conditions and anticipated regional climate change. Fire suppression has allowed the excessive growth of all age classes of timber. High density stands combined with the recent snow load damage has resulted in excessive ground and ladder fuels; especially in north aspect stands (see Fuels Specialist Report in Project Record). From a regional perspective, these types of conditions increase the risk for stand replacement wildfires to


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occur that may be larger and of higher intensity than what occurred prior to European settlement Peterson et al 2005). Compounding this risk further is the anticipated increase in temperature due to climate change. Climate change research suggests that summer temperatures are expected to continue to increase for Western North America (Running 2006) and specifically for the northern Great Plains (USGCRP 2009). Westerling et al (2006) found that increasing spring and summer temperatures over the last three decades has resulted in more frequent and longer duration large wildfires in the western U.S., and specifically in the Northern Rockies. McKensie et al (2004) suggests that the amount of area burned annually in western states will increase dramatically with increasing summer temperatures. Their research suggests that fire seasons in Montana, Wyoming and New Mexico, in particular, are acutely sensitive to summer temperatures and climate change. Refer to Section II. Affected Environment for a discussion of wildfire effects on water resources. The proposed vegetation treatments incorporate recommendations by Peterson et al (2005) for effective fuels management. The treatments would reduce timber stand density and ground, ladder and crown fuel loads, and therefore reduce the risk for stand replacement wildfire (see Fuels Specialist Report). The risk of impact to soil and hydrologic functions from stand replacement wildfire would be reduced compared to the no action alternative, but would not be totally eliminated. Accelerated soil erosion is still likely, depending on fire intensity and area burned. Soil erosion would be more localized and mosaic across the landscape than under the no action alternative. Channel adjustments from overland flow and sedimentation would still be expected, but again more localized than no action. These effects could still reach perennial stream segments on and off forest, but only through post-fire high intensity rain events. Previous wildfires on the district have also produced post-fire landscape responses; Ft Howes and Tobin Fire (Nienow 2002, USDA 2000a and 2000b), Watt Draw Fire (USDA 2006b). Stream systems would stabilize as vegetative recovery occurs during post-fire years and the recovery period should be more rapid than no treatment due to overall lower burn intensity and severity. Cumulatively, existing roads and grazing would compound the effects of post-fire precipitation events, but to a lesser degree than no treatment. Roads would increase surface and subsurface drainage efficiency, routing upslope waters to natural channels at higher rates, thereby increasing floodwater levels. Roads that restrict floodwater access to floodplains would also result in higher flood stage. Concentrated livestock trampling and trailing along watercourses can also increase drainage efficiency and destabilize stream banks. The combination of these conditions would increase the risk of more flood damage to streams and downstream human developments following a wildfire. The effects are expected to be highest in those drainages or subdrainages that burn with high intensity over a large area, and where road and livestock densities are high. Of the total 5.7 miles of new temporary roads, approximately three miles would be constructed along lower slopes adjacent to the bottom of draws, which could increase the risk of affecting water resources, even though the roads would be temporary and the draws may be ephemeral. This is primarily a cumulative effects issue where these roads could compound the effects of post wildfire flood events. The following temporary roads are located on lower slopes or within valley bottoms and adjacent to intermittent or ephemeral channels: 02, 03, 05, 06, 08, and 48. BMP’s and project design criteria would ensure these roads are not located in the absolute


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bottom of draws, which would reduce the potential for concentrated runoff in the draws from intersecting road surfaces. The risk is short-term assuming adequate and rapid rehabilitation. The risk of cumulative effects to water quality, water quantity and channel/floodplain/wetland functions are low due to proposed project activities, design features, and BMP implementation.

VI. EFFECTS OF ALTERNATIVE D ON WATER RESOURCES - NO ACTION ALTERNATIVE

Although vegetation treatments would not occur under this alternative, future natural disturbance events (wildfire, windthrow, flood) are still expected to occur. Ongoing human activities (grazing, agriculture, vehicle travel) are also expected to continue throughout the watersheds. All of these events and activities can affect hydrologic processes and beneficial uses. A. DIRECT EFFECTS There are no directs effects associated with the no action alternative. B. INDIRECT EFFECTS Timber stand density, conifer colonization into meadows, and ground and ladder fuels will continue to increase throughout the BCLMP area, thereby increasing the risk of stand replacement wildfire. As discussed previously in Section II: Affected Environment, wildfire events can impact water resources. C. CUMULATIVE EFFECTS Livestock grazing on and below the Forest, along with crop production on private lands are widespread, but generally concentrated along valley bottoms. Therefore, these activities are likely the major existing and chronic influence on water resources within the Beaver, Little Pumpkin and East Otter Creek watersheds. These activities have occurred for many decades in the past and are expected to continue well into the future. On NFS land, existing timber stand density would continue to limit livestock grazing distribution, which generally results in more grazing pressure/impact along perennial streams and wet meadows. The ECA estimates for past timber harvest, wildfire and existing roads suggest that these existing disturbances are too low to cause measureable increases in water yield or streamflows (Table 3.4.2). In the absence of large disturbance events, ECA acres for past harvest and wildfire would decline through recovery of the timber stands. Refer to the previous Section, II: Affected Environment, E. Human Influences. There would be no change in road impacts as a result of the no action alternative. Except for a small number of localized impacts, the existing transportation system within the BCLMP area has minimal influence on water quality. Most road segments are located along ridges or mid slopes, or are well vegetated with minimal vehicle use. Their location is of sufficient distance


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from most perennial streams to allow for dispersion of surface flow and deposition of sediment prior to reaching surface water. The exceptions are described in the previous Section, II: Affected Environment, E. Human Influences. In the absence of large disturbance events, these effects would continue under the no action alternative. Future natural disturbance events (fire followed by flood) would likely be the most detrimental to water resources from a pulse disturbance perspective. These events are expected to occur again and could be severe given current vegetative conditions and anticipated regional climate change. Fire suppression has allowed the excessive growth of all age classes of timber. High-density stands combined with the recent snow load damage, have resulted in excessive ground and ladder fuels, especially in north aspect stands. From a regional perspective, these types of conditions increase the risk for stand replacement wildfires to occur that may be larger and of higher intensity than what occurred prior to European settlement (Peterson et al 2005). Compounding this risk further is the anticipated increase in temperature due to climate change. Climate change research suggests that summer temperatures are expected to continue to increase for Western North America (Running 2006) and specifically for the northern Great Plains (USGCRP 2009). Westerling et al (2006) found that increasing spring and summer temperatures over the last three decades has resulted in more frequent and longer duration large wildfires in the western U.S., and specifically in the Northern Rockies. McKensie et al (2004) suggests that the amount of area burned annually in western states will increase dramatically with increasing summer temperatures. Their research suggests that fire seasons in Montana, Wyoming and New Mexico, in particular, are acutely sensitive to summer temperatures and climate change. This alternative does not reduce fuel loads and therefore continues the current level of risk for stand replacement wildfire. In the event of wildfire, and dependent on the intensity and area burned, accelerated soil erosion is likely, particularly if hydrophobic soils are formed. Significant channel adjustments from overland flow and sedimentation could be expected, especially during high intensity precipitation events. These effects would likely reach perennial stream segments on and off forest. Previous wildfires on the district have produced similar post-fire landscape responses; Ft Howes (Nienow 2002, USDA 2000c), Tobin (USDA 2000b) and Watt Draw Fire (USDA 2006b). Stream systems would however stabilize as vegetative recovery occurs during post-fire years, although the recovery period would be slower as fire intensity increased. Risk of impact to soil and hydrologic functions from stand replacement wildfire would continue to increase as fuel loads and summer temperatures increase in the future. However, it is not possible to estimate the size, location or intensity of future wildfires with a high degree of certainty. Cumulatively, existing roads and grazing would compound the effects of post-fire precipitation events. Roads would increase surface and subsurface drainage efficiency, routing upslope waters to natural channels at higher rates, thereby increasing floodwater levels. Roads along mainstem channels lower in the watersheds that restrict floodwater access to floodplains would also result in higher flood stage. Concentrated livestock trampling and trailing along watercourses can also increase drainage efficiency and destabilize stream banks. The combination of these conditions would increase the risk of more flood damage to streams and downstream human developments following a wildfire. The effects are expected to be highest in those drainages or subdrainages that burn with high intensity over a large area, and where road and livestock densities are high.


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VII. COMPARISON OF ALTERNATIVES

Under Alternatives A and B, one new stream crossing is proposed. Short-term sediment delivery to a perennial stream is anticipated, but the risk of long term effects to water resources is low. Under Alternative C and D, no new stream crossings are proposed, therefore there are no direct effects or risks.

Although treatment acres and treatment types vary by action alternative, the indirect effects to water resources are essentially the same, given the implementation of all reasonable BMPs. Under Alternative D, timber stand density, conifer colonization into meadows, and ground and ladder fuels would continue to increase throughout the BCLMP area without any vegetation treatments. The action alternatives reduce timber stand density and fuel loads, thereby reducing the risk of stand replacement wildfire and subsequent effects to soil and water resources compared to the no action alternative. Alternatives A and B reduce this risk more than Alternative C. However, none of the action alternatives eliminate all risk. Future wildfire is still likely within the analysis area, but the extent and the intensity of the wildfire should be lower with more proposed treatments implemented. New temporary road construction, including roads located on lower slopes or within valley bottoms is highest in Alternatives A and B and least in Alternative C. The risk of affecting water resources from compounding post-wildfire flood impacts is essentially low for all action alternatives, given the implementation of all reasonable BMPs. There is no risk from the No-action alternative. Alternatives A and B bring more road miles up to standard through maintenance and reconstruction than Alternatives C and D. However, Alternatives A and B also open more maintenance level 1 roads that are currently overgrown and vegetated than Alternatives C and D. All action alternatives obliterate the same miles of existing road (2.1), whereas under the no action alternative, no roads are planned for obliteration in the short-term. Therefore, risks to soil and water resources from these roads are eliminated under the action alternatives, but not under the no action alternative.

VIII. REQUIRED DISCLOSURES FOR ALTERNATIVES Short-term vs. Long-term Productivity There are no short-term versus long-term productivity issues for water resources under any alternative.

Irreversible/irretrievable Commitments There are no irreversible/irretrievable commitments on water resources under any alternative.


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Unavoidable Adverse Effects Roads systems and vegetation treatments cannot be designed to totally eliminate all potential effects to water resources, but they can be designed to minimize the effects to a substantial degree. Standard and project specific BMPs would be implemented to minimize sediment generation and downslope delivery to the greatest practical extent.

Compliance with Laws, Regulations and Policy Through the application of standard and project specific BMP’s, the action alternative would comply with all state and federal water quality laws, and Forest Plan Standards and Guidelines. Additionally, there is a very low risk of affecting the Tongue or Powder Rivers, or Otter Creek; Montana 303(d) listed streams located downstream from the analysis area.

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