FOSTER FIRS FOREST HEALTH AND FUELS REDUCTION PROJECT HYDROLOGY REPORT. May 27, Steve G. Markman, Hydrologist Eldorado National Forest

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1 FOSTER FIRS FOREST HEALTH AND FUELS REDUCTION PROJECT HYDROLOGY REPORT May 27, 2015 Meadow and forest adjacent to road 09N14. Anderson Canyon. Steve G. Markman, Hydrologist Eldorado National Forest

2 EXECUTIVE SUMMARY This report analyzes the impacts to aquatic resources that are likely to result from the Foster Firs Forest Health and Fuels Reduction Project, referred to as the Foster Firs Project in this report. The Foster Firs Project is located in the Amador Ranger District of the Eldorado National Forest in northern California. The landscape of the Foster Firs Project is mountainous and forested, and sits at the headwaters of the Cosumnes River and Mokelumne River drainage basins at an elevation between 6,120 and 7,720 feet. The Foster Firs Project (Alternatives 1, 3, and 4) would involve a number of activities that would likely start in 2016 and occur over several years. The major activities include: commercial and non-commercial thinning of trees, prescribed burning both within and outside of thinning units, restoration activities at a number of locations, reconstruction and maintenance of roads, and decommissioning of roads. The two largest streams in the project area are the perennial streams of the Middle Fork Cosumnes River and Anderson Canyon. There are a number of meadows in the project area. In the short-term (less than five years), the Foster Firs Project (Alternatives 1, 3, and 4) would result in minor or negligible effects to aquatic resources (water quality and quantity, stream condition, and aquatic habitat) in the project area and downstream of the project area. This is largely the result of the design criteria in Tables 5 and 6 of this report. In the long-term (greater than five years), Alternatives 1, 3, and 4 should result in the following: An improvement in water quality and aquatic habitat of Anderson Canyon and the Middle Fork Cosumnes River in the project area. This is largely the result the decommissioning of approximately1.3 miles of roads and associated road crossings of streams, which is expected to reduce the amount of runoff and sediment from roads into Anderson Canyon and the Middle Fork Cosumnes River. The condition of two meadows - the meadow at the beginning of the Middle Fork Cosumnes River and meadow 09N95-1 should improve as a result of treatments to road 09N95. The treatments to road 09N95 would also mean that Standard & Guideline #100 of the 2004 Sierra Nevada Forest Plan Amendment (SNFPA) would be met. Alternative 3 would likely result in a greater long-term benefit to the water quality and aquatic habit of Anderson Canyon and the Middle Fork Cosumnes River than Alternatives 1 and 4. This is because Alternative 3 would remove approximately8.6 miles of roads and associated road crossings of streams, which would likely result in a greater reduction in the amount of runoff and sediment from roads into Anderson Canyon and the Middle Fork Cosumnes River than Alternatives 1 and 4. Metrics with regard to roads for each alternative are in Table 4 of this report. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

3 As a result of the above, the Foster Firs Project (Alternatives 1, 3, and 4) would meet all of the Riparian Conservation Objectives (RCOs) and associated Standards and Guidelines (S&Gs) in the Sierra Nevada Forest Plan Amendment, Record of Decision (SNFPAROD) of January The analysis of the RCOs and associated S&Gs is contained in a separate document: Riparian Conservation Objectives Consistency Report. Alternative 2 (No Action) would likely not result in long-term improvement in water quality and aquatic habitat of Anderson Canyon and the Middle Fork Cosumnes River in the project area. Alternative 2 would also likely mean that two meadows the meadow near the end of road 09N95 and meadow 09N95-1 would continue to degrade and Standard & Guideline #100 of the SNFPA would not be met. The reason for these conclusions are that restoration activities, which includes the decommissioning of roads, would not occur. The risk of cumulative watershed effects (CWE) is currently either low or moderate in the three watersheds (HUC 7 scale) that contain the Foster Firs Project. Alternatives 1, 3, and 4 would increase the risk of CWE in the Anderson Canyon and Middle Fork Cosumnes River watersheds to high for two to four years. The risk of CWE in the Podesta watershed would remain low under all alternatives. None of the alternatives would result in any watershed exceeding the Threshold of Concern and none of the watersheds would be at a very high risk of CWE. As a result of the above, the risk of CWE is not significant. AFFECTED ENVIRONMENT and EXISTING CONDITION The Foster Firs Forest Health and Fuels Reduction Project - referred to as the Foster Firs Project in this report - is located in the Amador Ranger District of the Eldorado National Forest in northern California. The landscape of the Foster Firs Project is mountainous and forested at an elevation between 6,120 and 7,720 feet (Figure 1). Most of the Foster Firs Project sits at the headwaters of the Cosumnes River drainage basin and a small portion of the project area is in the Mokelumne River drainage basin (Figure 2). The Foster Firs Project includes a portion of three watersheds at the HUC 7 scale (Figures 2 and 3). The two largest streams in the project area are the perennial streams of the Middle Fork Cosumnes River and Anderson Canyon. Both streams flow to the west/southwest, and Anderson Canyon flows into the Middle Fork Cosumnes River (Figure 3). The Middle Fork Cosumnes River flows into the Cosumnes River more than 19 miles to the west of the project area. There are also a number of meadows in the project area. Physical characteristics of the Foster Firs Project are summarized in Table 1. Selected aquatic features are described in Table 2 and illustrated in Figures 5 through 9. The flow of Anderson Canyon and the Middle Fork Cosumnes River is illustrated in Figure 14. Additional photographs of aquatic features and other features are in Appendix A. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

4 Figure 1. A view of a portion of the Foster Firs Project area, as seen from road 09N14K looking to southwest towards Anderson Canyon. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

5 Figure 2. Location of the watersheds (HUC 7 scale) of the Foster Firs Project with respect to the Cosumnes and Mokelumne Rivers. Cosumnes River ANDERSON CANYON PODESTA Middle Fork Cosumnes River UPPER MIDDLE FORK COSUMNES RIVER Bear River Reservoir Salt Springs Reservoir Mokelumne River ² HUC 7 watershed Boundary of Foster Firs Project Perennial stream Miles Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

6 Figure 3. Watersheds (HUC 7 scale), streams, and roads of the Foster Firs Project. 1 09N14A 09N02 09N14 10N50 09N67 09N02B 09N02A 09N02 09NY11A 09N14 09N14B 09N14C 09N14D 09N68A 09N68 Watershed boundary 09NY11 09N14K ANDERSON CANYON AN4 Anderson Canyon AN3 AN2 09N14 NSR 09N14M AN1 09N95 Highway 88 09N96C 09N96 Thinng areas of the Foster Firs Project NSR 09N68 09N95B 09N95 09N14L PODESTA Boundary of Foster Firs project area Middle Fork UPPER MIDDLE FORK COSUMNES RIVER Cosumnes 09N14 River 09N14H 09N14 09N96A 09N96 Perennial stream Intermittent stream ² Road Miles 0 1,000 2,000 4,000 Feet 1 The Environmental Assessment contains detailed maps of the thinning areas of the Foster Firs Project. The roads in this map depict the roads as shown in GIS and may not exactly correspond to the location and lengths of roads on-the-ground. Consult the current Motor Vehicle Use Map (MVUM) for roads open to the Public. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

7 Table 1. Physical characteristics of the Foster Firs Project. Location Terrain Drainage basins and HUC 7 watersheds 1 Climate Aquatic features Aquatic life Geology and Soils Beneficial uses of water 1 Southern portion of the Eldorado National Forest on the north side of highway 88, California. Approximately 27 air miles southwest of South Lake Tahoe, California. Approximately 36 air miles Northeast of Jackson, California. Mountainous and forested. Mostly mixed conifer forest. Most of the project area is between 6,120 and 7,720 feet in elevation. Cosummnes River drainage basin. 936 square miles (total). Upper Middle Fork Cosumnes River watershed (#2481). 9,218 acres. Anderson Canyon watershed (#2491). 3,328 acres. Mokemne River drainage basin. 2,143 square miles (total). Podesta watershed (#1311). 3,657 acres. Average annual precipitation is approximately 55 to 60 inches. Much of the precipitation falls between October and April, and the precipitation during this time period is frequently snow. Thunderstorms can occur in the summer. There are approximately 3.9 miles of perennial streams and 24.4 miles of intermittent and ephemeral streams in the project area. Most of the 3.9 miles of perennial streams occur in Anderson Canyon and the Middle Fork Cosumnes River (Figure 3). Both streams flow to the west and southwest. A number of meadows are contained within the project area. The condition of selected aquatic features is described in Table 2. Rainbow trout (Oncorhynchus mykiss) occur in all of the perennial streams in the project area. Rainbow trout can occur in the intermittent streams when they are flowing. Habitat for Sierra Nevada Yellow legged frog (Rana sierrae) occurs in Anderson Canyon, the Middle Fork Cosumnes River, and several intermittent streams in the project area. An aquatic lichen (Peligera hydrothyria), a Forest Service sensitive species, occurs in a segment of several streams. Approximately 32 percent of the project area is granitic rocks of the Sierra Nevada batholith. These are the oldest rocks in the project area, and are found primarily near Anderson Canyon. Approximately 66 percent of the project area is volcanic rocks of the Mehrten Formation, and most of the volcanic rocks are andesitic lahars. Most of the thinning Units of the Foster Firs Project are in these volcanic rocks. A geologic map of the project area is in Appendix A. The soils can be described in terms of five Generalized Soil Groups, and are described in detail in the Soils Report (Nicita 2015). Municipal water supplies for domestic use; hydropower generation; contact and non-contact. recreation; canoeing and rafting; cold freshwater habitat; spawning habitat; and wildlife habitat. 303(d) listed water bodies 2 The entire Cosumnes River is on the 303(d) list for exotic species. 3 Land disturbances Past timber harvest - cut tree stumps and skid trails - is evident throughout the project area and immediately adjacent to a number of streams. The density of roads in the project area is high, and there are many locations where roads cross streams (Table 3). In a few locations, roads are contributing runoff and sediment into downslope areas (Figure 12). Off-road vehicle (OHV) use and camping are on-going activities near several streams. 1 The watersheds (HUC 7 scale) are shown in Figure 3. Approximately 6.0 acres of the Foster Firs Project may occur in the Upper North Fork Cosumnes River watershed - this is less than 0.8 percent of the watershed. 2 Beneficial uses of water are designated by the Central Valley Regional Water Quality Control Board (CVRWQCB). 3 Refers to Section 303(d) of the Clean Water Act, which gives states the authority to identify bodies of water that are impaired. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

8 Table 2. Summary of selected aquatic features in the Foster Firs Project. 1,2,3,4,5 Aquatic feature Type of feature Proximity to Units of the Foster Firs Project Characteristics Condition rating Anderson Canyon Perennial stream Units border approximately 5,140 feet (24.1 percent) of the length of the stream (in the project area and within the Riparian Conservation Area.) Flows to the west southwest and into the Middle Fork Cosumnes River. Length of the stream is approximately 2.6 miles within the project area. The RCA adjacent to the stream is approximately 94.5 acres this is 2.8 percent of the watershed. Surface flow is year-round (perennial). Flow can decrease to less than 2.0 cubic feet per second (cfs.) in late summer and early fall. Channel varies in character. Low gradient segments (pools, riffles, and runs flowing over alluvial material) alternate with moderate or high gradient segments (flowing over bedrock and large boulders). Water quality is fairly good, based on limited parameters and measurements. ph = 7.0 to 7.8 (near nuetral); conductivity = 12 to 80 us (indicates fairly low concentrations of dissolved solids); turbidity < 7.0 NTU (indicates low concentrations of suspended sediment). 4 However, road 09N14 is contributing sediment into the stream during rainfall events (Figure 13). Fairly good condition throughout much of the stream. Much of the stream in Unit 10 is low gradient and meandering through a floodplain. Active stream channel erosion at a number of meander bends. Much of the stream downstream of Unit 10 is moderate gradient. The streambanks are generally stable, and segments of the lowermost portion of the stream flow through granitic bedrock or large boulders. Moderate amounts of fine-grained sediment in the channel. Abundant riparian vegetation next to stream. Water temperatures in the summer are cool. Large woody debris is functional, but somewhat lacking in amount. One camping area near the end of road 09N14M is encroaching toward the stream. Photographs of Anderson Canyon are shown in Figures 5 and 6. 1 The location of streams is shown in Figure 3. 2 Stream condition ratings are based on field surveys and observations in 2012 and RCA = Riparian Conservation Area. The RCA - a land allocation defined in the 2004 Sierra Nevada Forest Plan Amendment - is 300 feet on each side of perennial streams and special aquatic features and 150 feet on each side of intermittent and ephemeral streams. 4 Water quality measurements were taken in the summer and fall of The measurements represent low flow conditions and may not represent the water quality during high flow conditions. 5 Additional photographs of aquatic features are in Appendix A. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

9 Table 2 (continued). Description of selected aquatic features in the Foster Firs Project. Aquatic feature Type of feature Proximity to Units of the Foster Firs Project Characteristics Condition rating Middle Fork Cosumnes River Perennial stream Units border approximately 1,450 feet (12.4 percent of the length of the stream in the project area and within the Riparian Conservation Area). Streams flows to the west and into the Cosumnes River. Length of the stream in the project area is approximately 5,810 feet (1.1 miles). Surface flow is year-round (perennial). Flow can decrease to less than 1.0 cubic feet per second (cfs.) in late summer and early fall Channel generally less than 30 feet in width. Fairly good condition for much of the stream upstream of road 09N14. Stable streambanks. Little or no excessive stream channel erosion (both vertical and lateral). Riparian vegetation present. Large woody debris is functional, but may be somewhat lacking in amount. Shade on stream surface adequate to maintain cool water temperatures. A photograph of a segment of the Middle Fork Cosumnes River is shown in Figure 7. Meadow at the end of road 09N95 Meadow A commercial thinning Unit borders the top of the meadow. The meadow is approximately 3.5 acres in size. The meadow sits at the beginning of the Middle Fork Cosumnes River, and this stream flows through the meadow. Road 09N95 borders the top of the meadow. The meadow is in a degraded condition and does not meet Standard & Guideline #100 of the Sierra Nevada Forest Plan Amendment (January 2004). 1 There are two reasons for this: Runoff from two road segments has eroded sediment into the meadow such that the size and/or wetness of the meadow has been reduced. Runoff from two road segments, as well as the acceleration of streamflow through a culvert underneath one road segment, has caused portions of the stream channel to downcut such that the water table next to the stream has dropped and the size and/or the wetness of the meadow has decreased. A photograph of a portion of the meadow is shown in Figure 8. Meadow 09N95-1 Meadow No thinning units are near the meadow. Located just upstream of where Foster Meadow Road (09N14) crosses the Middle Fork Cosumnes River. The meadow does not meet Standard & Guideline #100 of the Sierra Nevada Forest Plan Amendment (January 2004). 1 Runoff from road 09N95 has created an eroding channel that is contributing a large amount of sediment into the meadow. A photograph of a portion of the meadow is shown in Figure 7. 1 Standard & Guideline #100 states: Maintain and restore the hydrologic connectivity of streams, meadows, wetlands, and other special aquatic features by identifying roads and trails that intercept, divert, or disrupt natural surface and subsurface water flow paths. Implement corrective actions where necessary to restore connectivity. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

10 All streams Ephemeral Intermittent Perennial No. of road crossings per mile of stream Miles Density (miles / square mile) Miles Square miles Acres Table 3. Summary of the existing metrics with regard to roads in the Foster Firs Project area. 1,2,3,4 Roads Streams (all types) Number of road crossings by stream type Foster Firs Project area 3, The information this table only represents the Foster Firs project area (3,507 acres) road segments outside of the project area are not included. 2 The information in this table is from GIS and not from an on-the-ground survey. As a result, the information in this table may be slightly different on-the-ground. 3 Metrics with regard to roads are in the Middle Cosumnes River Watershed Landscape and Roads Analysis (USDA 2002). However, the road metrics in that document are at a larger scale than the Foster Firs project area. 4 Most of the stream crossings are culverts underneath the surface of the road, as shown in Figure 4. Figure 4. Road 09N14 (Foster Meadow Road) crosses the Middle Fork Cosumnes River. The entire river flows through the culvert underneath the road. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

11 Figure 5. Anderson Canyon in Unit 10. Much of the stream in Unit 10 is low gradient and meanders through a floodplain, and there is active channel erosion occurring at a number of meander bends. Unit 10 is a commercial thinning unit adjacent to Anderson Canyon and stream AN1 (Figure 3). Figure 6. Anderson Canyon just downstream of Unit 10. The gradient of the stream has increased, the floodplain is narrow, there is little meandering of the stream, and the substrate is dominated by gravel, cobbles, and boulders. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

12 Figure 7. Middle Fork Cosumnes River just upstream of road 09N14. The floodplain is well-developed, and a meadow (09N95-1) has developed in a portion of the floodplain. Figure 8. Meadow near the end of road 09N95. Runoff from two roads has caused the stream channel to downcut; this has resulted in a drop in the water table in the portions of the meadow (note the lack of riparian vegetation on the left side of the stream channel). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

13 Figure 9. Large meadow adjacent to Anderson Canyon and Unit 10. Unit 10 is a commercial thinning unit adjacent to Anderson Canyon and stream AN1 (Figure 3). Figure 10. Camping area near Anderson Canyon and Unit 10. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

14 Figure 11. The north side of Anderson Canyon has areas of granitic rocks and shallow soils derived from granitic rocks. These areas, which tend to have little or no vegetation, have high runoff and erosion rates which in turn contributes runoff and sediment into the perennial stream of Anderson Canyon. This is also documented in the Middle Cosumnes River Watershed Landscape and Roads Analysis (USDA 2002). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

15 Figure 12. Much of road 09N14K (north side of Anderson Canyon) cuts through granitic rocks and shallow soils developed from granitic rocks. A large amount of runoff and sediment from this road is contributed to downslope areas. Figure 13. A small amount of runoff and sediment from road 09N14 (middle of photo where the water is ponded) reaches a tributary of Anderson Canyon (bottom of photo at culvert) during rainfall events. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

16 Cubic feet per second (cfs.) Figure 14. Estimates of the streamflow of Anderson Canyon and Middle Fork Cosumnes River (upstream of Anderson Canyon) for different flow events year peak flow 5-year peak flow 10-year peak flow 25-year peak flow year peak flow 100-year peak flow Anderson Canyon Upper Middle Fork Cosumnes River (upstream of Anderson Canyon) 5.10 square miles 3.00 square miles 1 Based on information from the U.S. Geological Survey at the internet site:

17 DIRECT AND INDIRECT EFFECTS Alternative 2 (No Action) There are several effects to aquatic resources that would occur from Alternative 2 (No Action) when compared to Alternatives 1, 3, and 4. Long-term improvement (greater than five years) to the water quality and aquatic habitat of the Middle Fork Cosumnes River and Anderson Canyon may not occur. There are several reasons for this conclusion. The decommissioning of road segments that are contributing sediment into streams would not occur. These road segments include: a) a segment of road 09N95, which is contributing sediment into the Middle Fork Cosumnes River, b) road 09N14L, which crosses four ephemeral streams that flow into the Middle Fork Cosumnes River, and c) road 09N14D, which is contributing sediment into three ephemeral streams that flow into Anderson Canyon. The reconstruction and/or maintenance of approximately 28 miles of roads in the project area would not occur. A number of these roads cross the Middle Fork Cosumnes River and Anderson Canyon and/or their tributaries. The restoration activities described in the Environmental Assessment (Table 2: Foster Firs Soils and Watershed Restoration Items) would not occur. This includes the restoration of skid roads, landings, dispersed recreation sites, eroding areas at a number of locations. A number of these sites are located near streams. Improvement to the condition of several other aquatic features would likely not occur. The meadow near the end of road 09N95 would likely continue to degrade. This is because the removal of two road segments (0.4 miles in total length) at the end of road 09N95, which are delivering runoff and sediment into the meadow, would not occur. The location of the two road segments and the meadow is shown in Figure 18. The condition of the meadow is described in Table 2 and shown in Figure 8. Meadow 09N95-1, located just upstream of where Foster Meadow road (09N14) crosses the Middle Fork Cosumnes River (Figure 7), would not meet Standard & Guideline #100 of the Sierra Nevada Forest Plan Amendment of This is because treatments to road 09N95, which would reduce the amount of runoff into an eroding channel that is delivering sediment to the meadow, would not occur. The wetland vegetation surrounding Podesta Camp Spring would likely continue to be removed as a result of livestock use. This is because a fence would not be constructed around the spring and associated wetland vegetation and, as a result, livestock would continue to use the aquatic feature without restriction. A photograph of the spring is in Appendix A. A segment of an intermittent stream on the south side of road 09N68 in the Podesta watershed would likely continue to show excessive channel erosion and lack of riparian vegetation. Part of the reason for this Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

18 conclusion is that trees would not be felled near the stream so as to discourage the use of the stream by livestock. A photograph of a segment of the stream is in Appendix A. There would be a greater risk of adverse effects to aquatic resources as a result of a high severity wildfire. The hydrologic response to a high severity wildfire is well documented in the literature. Runoff and erosion rates increase by two or more magnitudes for several years after a high severity fire, and frequently decline to near prewildfire levels within four or five years (Figure 15). Since the Foster Firs Project includes a portion of three watersheds (HUC 7 scale), there is the potential for a high-severity fire to affect all of the streams shown in Figure 3. The potential effects within and downstream of the project area include the following: An increase in the suspended sediment and turbidity levels of streams during and immediately after rainfall events and periods of rapid snowmelt (Figure 16). This can directly affect the health and survival of fish and other aquatic organisms. For example, the growth of rainbow trout (Onchorhychus mykiss) decreases when turbidity pulses of 23 NTU occur over a number of days (Shaw and Richardson 2001). Deposition of fine-grained sediment in stream channels, which can reduce the amount and quality of habitat for all life phases of fish (Figure 17). This effect can last for many years after runoff and erosion rates in the wildfire area have declined to pre-burn levels. A fire in the project area would likely not affect municipal drinking water supplies. There are no drinking water supplies downstream of the portion of the project area that includes Anderson Canyon and the Middle Fork Cosumnes River. The Bear River Reservoir is located more than three miles downstream of the small portion of the project area within the Podesta watershed. It should be noted, however, that the effects to aquatic features and beneficial uses of water both within and downstream of a high severity wildfire are difficult to predict and depend on many factors. The single most important factor is often the size of the rainfall event that occurs during the first several years after the wildfire - when the ground is most vulnerable to accelerated runoff and erosion (USDA 2010; Dissmeyer 2000). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

19 Erosion in kilograms/hectare Figure 15. Erosion following a wildfire in eastern Oregon (Robichaud and Brown 1999) percent slope percent slope Year 1 Year 2 Year 3 Year 4 1 Erosion rates represent hillslope erosion, not the amount of sediment delivered to streams. Note that the vertical scale is logarithmic - erosion decreased three orders of magnitude between year 1 and 4 after the fire. (1 hectare = acres; 1 kilogram = 2.2 pounds. Figure 16. Turbidity of water samples from streams after the Power Fire of 2004, Eldorado National Forest. 1 NTU Cole Creek 34 NTU Beaver Creek 77 NTU East Panther Creek 71 NTU Tiger Creek 230 NTU Tributary of Beaver Creek The Power Fire occurred in October The above water samples were taken on December 8, 2004, after approximately 2.76 inches of rain. Turbidity is measured in Nephelometric Turbidity Units (NTU). The Power Fire is located to the southeast of the Foster Firs Project. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

20 Figure 17. Fine-grained sediment (less than 2.0 millimeters in diameter) covers a segment of the stream channel of East Panther Creek within and downstream of areas of high and moderate burn severity from the Power Fire of (Nov. 2004). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

21 Alternative 1 (Proposed Action) In the short-term (less than five years), effects to aquatic resources (water quality and quantity, condition of streams and meadows, and aquatic habitat) in the project area are expected to be minor or negligible. In the long-term (greater than five years), there is expected to be: An improvement in the water quality and aquatic habitat of Anderson Canyon and the Middle Fork Cosumnes River in the project area. An improvement in the condition of Meadow 09N95-1 and the meadow near the end of road 09N95. An improvement in Podesta Camp Spring. As a result of the above, Alternative 1 (Proposed Action) would meet all of the Riparian Conservation Objectives (RCOs) and associated Standards and Guidelines (S&Gs) in the Sierra Nevada Forest Plan Amendment, Record of Decision (SNFPAROD) of January The analysis of the RCOs and associated S&Gs is contained in a separate document: Riparian Conservation Objectives Consistency Report. The reasons for the above conclusions are described in detail below. 1. A minor, short-term (less than five years) increase in the suspended sediment concentrations and turbidity levels of the streams that flow through or adjacent to Units of the Foster Firs Project may occur during and immediately after large rainfall events. This increase - should it occur - should not exceed state water quality standards for turbidity or sediment. The reasons for this conclusion are listed below. A.) A number of protection measures would minimize the amount of sediment delivered to the streams as a result of the Foster Firs Project (Tables 5 and 6). The single most important protection measure in this regard is the zone of no ground disturbing activities (or buffer zones ) adjacent to streams and other aquatic features. All aquatic features in the project area have such buffer zones, ranging from feet next to perennial and intermittent streams and feet for ephemeral streams. There are a number of research studies that have shown that the effects of timber harvest activities on aquatic habitat and aquatic species are minimized if there are no timber harvest activities within 100 feet of the stream (Sierra Nevada Ecosystem Project 1996; Parkyn 2004). It should be noted, however, that the effectiveness of buffer zones in removing sediment before reaching a stream depends on a number of site-specific factors such as slope, soil type, degree of ground disturbance outside of the buffer zone, size of ground disturbance outside of the buffer zone, and type of vegetation in the buffer zone. The design features in Tables 5 and 6 for aquatic features and Riparian Conservation Areas (RCAs) reflect these factors as a result of site specific field visits by resource specialists (Hydrologist, Soil Scientist, and Fisheries Biologist). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

22 B.) Ground-disturbing activities would occur in a relatively small percentage of the Riparian Conservation Areas (RCAs) next to streams. (The RCA is 300 feet on each side of perennial streams and 150 feet on each side of intermittent and ephemeral streams). Ground disturbing activities would occur in zero percent of the RCA of the Middle Fork Cosumnes River. This is because timber harvest units are more than 300 feet from this stream. Ground disturbing activities would occur in approximately 1.5 percent of the RCA of Anderson Canyon. Ground disturbing activities would occur in approximately 4.1 to 10.3 percent of the RCA of four intermittent streams than flow into Anderson Canyon. These streams are labeled in Figure 3 as AN1, AN2, AN3, and AN4. Ground disturbing activities would occur in zero percent of the RCA of the meadow near the end of road 09N95. This is the result of the design criteria in Table 6. Ground disturbing activities would occur in zero percent of the RCA of Meadow 09N95-1. This is because there are no commercial or pre-commercial thinning Units in the RCA of Meadow 09N95-1. The calculations of ground-disturbing activities in the RCAs of streams consider: a.) the number of acres of RCA both within and outside of harvest units, b.) the width of the equipment exclusion zone adjacent to the streams within the commercial harvest units, and c) estimates of the amount of ground-disturbing activities within the zone of groundbased equipment, and d) the definition of ground-disturbing activities as defined in the SNFPA of 2004, which says: Activities that result in detrimental soil compaction or loss of organic matter beyond the thresholds identified by soil quality standards. Additional information with regard to ground-disturbing activities in the RCAs, including calculations for specific streams, is in Appendix A. Ground-disturbing activities and soil quality standards are discussed detail in the Soils Report (Nicita 2015). C.) Best management practices (BMPs) would be implemented during project operations that are designed to protect water quality, soils, and vegetation. The implementation and effectiveness of the BMP s from 2008 through 2012 in the Pacific Southwest Region of the U.S. Forest Service is summarized below. Approximately 91 percent of the prescribed BMPs were implemented on-the-ground. This includes all major activities timber, roads, recreation, grazing, fuels, mining, and vegetation management. Approximately 80 percent of the implemented BMPs were rated as effective, 14 percent were rated as at risk, and 6 percent were rated as not effective. This includes all major activities. For timber related activities alone, approximately 88 percent of the implemented BMP s Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

23 were rated as effective. For fuels related activities alone, approximately 92 percent of the implemented BMP s were rated as effective. For road related activities alone, approximately 68 percent of the implemented BMP s were rated as effective. Approximately 98 percent of the 2,237 on-site evaluations found that there were no significant adverse impacts on water quality (USDA 2012). The BMP monitoring fulfills commitments by the U.S. Forest Service to the State Water Quality Resources Control Board. The BMPs are described in: Water Quality Management Handbook for Forest System Lands in California, Best Management Practices (December 2011). D.) There would be no construction of new, permanent roads. In forested watersheds that contain roads, the roads are frequently a major source of sediment that reaches streams and other aquatic features (Dissmeyer 2000). 2. The effects to the water quality of streams - outside of suspended sediment and turbidity (discussed in item #1) - should be negligible or minor. Specific water quality parameters are discussed below. A.) Temperature. The reduction in the amount of shade on the surface of perennial streams from trees would be minor because the design criteria in Tables 5 and 6 greatly limit the number of trees and other vegetation that can be removed within 75 to 150 feet of perennial streams. According to a stream temperature model, the maximum potential stream temperature increase would be zero for the Middle Fork Cosumnes River and 2.1 degrees Fahrenheit for Anderson Canyon. The calculations and assumptions are in Appendix A. It should be noted that for small streams in a forested setting, the research indicates that elevated water temperatures usually decrease to pre-disturbance levels within 500 feet downstream of the zone of vegetation removal (USDA 2010). Intermittent and ephemeral streams have no surface flow during the time of year (early summer to early fall) when an increase in stream temperature is the most likely to occur. B.) Nutrients. The bulk of the published research has shown that increases in the nutrient levels of streams as a result of prescribed fire and the burning of slash piles are minor or negligible and short-term. The published research is summarized in Appendix A. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

24 3. In the short-term (less than five years), impacts to the water quality of Anderson Canyon and the Middle Fork Cosumnes River should be minor or negligible. The suspended sediment and turbidity levels of streams flowing through or adjacent to Units of the Foster Firs Project should not exceed state standards for turbidity and suspended sediment. The reasons for this conclusion are described under #1. The flow of the Middle Fork Cosumnes River downstream of the project area is much larger than the combined inflow of its tributaries in the project area. As a result, inputs of sediment from the streams that flow through or adjacent to Units of the Foster Firs Project would be quickly diluted by the much larger Middle Fork Cosumnes River. The increase to the temperature of the Middle Fork Cosumnes River and Anderson Canyon should be none or minor. The reasons for this conclusion have been previously described in #2. 4. In the long-term (greater than five years), there would be less runoff and sediment delivered from roads into the perennial streams of Anderson Canyon and the Middle Fork Cosumnes River as a result of Alternative 1 (Proposed Action) when compared to Alternative 2 (No Action). This is expected to result in a slight long-term benefit in the aquatic habitat of Anderson Canyon and the Middle Fork Cosumnes River in the project area. The benefits to aquatic habitat may include one or more of the following: a.) a decrease in the amount in fine-grained sediment in the stream channel, b.) an increase in the depth of pools, and c.) an increase in the number of pools. The reasons for these conclusions are described below. Approximately 1.3 miles (5.0 percent) of the roads in the project area would be decommissioned under Alternative 1. This would slightly reduce the density of roads and the number road crossings of streams in the project area when compared to Alternative 2 (No Action) as shown in Table 4. The road segments that would be decommissioned are: a) a 0.4 mile segment of road 09N95, which is eroding sediment into the Middle Fork Cosumnes River and an adjacent meadow, b) road 09N14L, which crosses four ephemeral streams that flow into the Middle Fork Cosumnes River, and c) road 09N14D, which erodes sediment into an ephemeral stream that flows into Anderson Canyon. Maps showing the roads and the road crossings of streams for each alternative are in Appendix A. A 0.5 mile long segment of road 9N95 would be improved so as to reduce the amount of runoff and sediment reaching meadow 09N95-1 and the Middle Fork Cosumnes River. The improvements include: a) installation of one additional cross drain with an inlet riser, b) ditch reconstruction along the road and installation of a riser on the existing cross drain, and c) placement of rip-rap on the outlet of the culvert. Approximately 28 miles of roads in the project area would receive reconstruction and/or maintenance. This is expected to reduce the amount of road-related sediment that is delivered to nearby streams in the long-term. The Environmental Assessment contains the Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

25 list of roads that would receive reconstruction and/or maintenance, as well as a detailed description of activities that are included in road reconstruction and maintenance. The research has shown that: a) the effects of roads on aquatic habitat and species are overwhelmingly negative, b) roads contribute more sediment to streams than any other land management activity, c) the closure or removal of roads can result in a significant drop in surface erosion rates, but the amount of decrease in erosion is highly variable, d) the correlation between road density and fish habitat and fish population is not strong part of the reason for this is that roads are only one of many factors that affect aquatic habitat and species (Dissmeyer 2000; USDA 2001). 5. Changes to the water yield, peak flow, and timing of flow of all streams in the project area and downstream as a result of fuels reduction activities are likely to be negligible and not measurable. The research indicates that fuels reduction treatments in forested watersheds have little detectable impact on water yields either on-site or downstream. Most prescriptions are not likely to remove the 20 percent of the basal area that is needed in most areas to generate a detectable change in flow. (USDA 2010). 6. The decrease in the recruitment of large woody debris (LWD) to perennial and intermittent streams in the Foster Firs Project as a result of the removal of trees should be minor. This is largely because few trees within one site-potential tree height would be removed as result of the design criteria in Tables 5 and 6. The research has shown that approximately 96 percent of the LWD that reaches streams is from within a ground distance of one site potential tree height of the stream channel (Reid and Hilton 1998). 7. In the long-term, the condition of several other aquatic features should improve. The meadow near the end of road 09N95 (at the beginning of the Middle Fork Cosumnes River) would likely improve. This is because of the removal of two road segments (0.4 miles in total length) at the end of road 09N95, which are delivering runoff and sediment into the meadow. The location of the two road segments and the meadow are shown in Figure 18. The meadow is also described in Table 2 and shown in Figure 8. The condition of Meadow 09N95-1, located just upstream of where Foster Meadow road (09N14) crosses the Middle Fork Cosumnes River, should improve. This is because improvements to a 0.5 long segment of road 09N95 would reduce the amount of runoff into an eroding channel that is delivering sediment to the meadow. The improvements to the segment of road 09N95 include: a) installation of one additional cross drain with an inlet riser, b) ditch reconstruction along the road and installation of a riser on the existing cross drain, and c) placement of rip-rap on the outlet of the culvert. These improvements to the segment of road 09N95 will also allow Meadow 09N95-1 to meet Standard and Guideline #100 of the 2004 Sierra Nevada Forest Plan Amendment. (Meadow 09N95-1 was rated as not meeting S&G #100 on November 1, The primary reason was the delivery of runoff from road 09N95 that created an actively eroding Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

26 channel which in turn has contributed large amounts of sediment into the meadow). The amount of wetland vegetation surrounding Podesta Camp Spring would likely increase. This is because a fence would be constructed around the spring to exclude livestock. A segment of an intermittent stream on the south side of road 09N68 in the Podesta watershed may improve. Specifically, erosion of the stream channel may decrease and the amount of riparian vegetation may increase. This is because trees would be felled near the stream so as to discourage the use of the stream by livestock. 8. There would be less risk of adverse effects to aquatic resources as a result of a high severity wildfire. The adverse effects to aquatic resources that may occur from a high severity wildfire have been previously discussed in detail under Alternative 2 (No Action). Alternative 3 The direct and indirect effects from Alternative 3 are mostly the same as for Alternative 1 (Proposed Action). The primary reason for this is that the design features to protect aquatic features are the same for Alternatives 1 and 3. However, there is one difference in the effects between Alternative 3 and all of the other alternatives. In the longterm, there would be substantially less runoff and sediment delivered from roads into the perennial streams of Anderson Canyon and the Middle Fork Cosumnes River as a result of Alternative 3 when compared to all of the other alternatives. This should benefit the water quality and aquatic habitat of Anderson Canyon and the Middle Fork Cosumnes River in the project area to a greater degree than Alternatives 1 and 4. 1,2 The long-term benefits to aquatic habitat may include one or more of the following: a.) a decrease in the amount in fine-grained sediment in the stream channel, b.) an increase in the depth and/or number of pools, and c.) a decrease in stream channel erosion. The reasons for these conclusions are described below. Approximately 8.6 miles (32.8 percent) of the roads in the project area would be decommissioned under Alternative 3. This would substantially reduce the density of roads and the number road crossings of streams in the project area when compared to all of the other alternatives (Table 4). Specifically, the number of road crossings of streams would be reduced by 48 percent when compared to Alternative 2 (No Action) and 33 percent when compared to Alternatives 1 and 4. Most of this reduction involves ephemeral streams; the number of intermittent and perennial streams crossed by roads is similar for all alternatives. Maps showing the roads and the road crossings of streams for each alternative are in Appendix A. 3,4 1 The length of Anderson Canyon and the Middle Fork Cosumnes River in the project area is approximately 2.4 and 1.1 miles, respectively. 2 The effects to individual aquatic species are discussed in the Biological Assessment/Evaluation for the Foster Firs Project. 3 The decommissioning of a road means that all structures would be removed, the surface of the road would be ripped, the ground surface may be reshaped at certain locations, and the entrance to the road would be blocked. 4 The 8.6 miles of road decommissioning includes approximately 8.3 miles of system roads and 0.3 miles of non-system roads.. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

27 Eleven of the 14 roads that would be decommissioned under Alternative 3 cross the perennial streams of Anderson Canyon and the Middle Fork Cosumnes River and/or tributaries of those streams. The research has shown that: a) the effects of roads on aquatic habitat and aquatic species are overwhelmingly negative, b) roads contribute more sediment to streams than any other land management activity, c) the closure or removal of roads can result in a significant drop in surface erosion rates, but the amount of decrease in erosion is highly variable, d) the correlation between road density and fish habitat and fish population is not strong part of the reason for this is that roads are only one of many factors that affect aquatic habitat and aquatic species (Dissmeyer 2000; USDA 2001). The last two items (c and d) mean that it is not currently possible to give numerical predictions of aquatic habitat and aquatic species as a result of the removal of roads. Table 4. Metrics with regard to roads in the Foster Firs Project area for each alternative. 1,2,3 Roads Streams Number of road crossings of streams Length (miles) Density (miles / square mile) Length (miles) No. of road crossings per mile of stream Perennial streams Intermittent streams Ephemeral streams All streams Alternative 2 (no action) Alternatives 1 and Alternative The Foster Firs project area is approximately 3,507 acres (5.48 square miles) in size. The information this table only represents the Foster Firs project area road segments outside of the project area are not included. 2 The information in this table is from GIS and not from an on-the-ground survey. As a result, the information in this table may be slightly different on-the-ground. 3 Metrics with regard to roads are in the Middle Cosumnes River Watershed Landscape and Roads Analysis (USDA 2002). However, the road metrics in that document are at a larger scale than the Foster Firs project area. Alternative 4 The direct and indirect effects from Alternative 4 are the same as for Alternative 1 (Proposed Action). There are two reasons for this conclusion. The design features to protect aquatic features in Tables 5 and 6 are the same for Alternatives 1 and 4. The road segments that would be decommissioned are the same for Alternatives 1 and 4. Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

28 Table 5. Equipment exclusion zones for aquatic features for the Foster Firs Project. Ground-based equipment exclusion zone (feet) 1,8 0 5 % slope 5-25 % slope % slope > 35 % slope Perennial stream 5, Intermittent stream 5, Ephemeral stream Draw , 6, 7 Large Meadows (> 1.0 acres) Small Meadows 3 (0.1 to 1.0 acres) Requires approval from a resource specialist after an onsite visit. Special aquatic feature (other than meadows) 1 For streams, as measured from the edge of the channel or riparian vegetation, whichever is greater. Reach-in (approximately 20 feet) is allowed to remove vegetation, unless specifically stated otherwise. 2 For draws, as measured from the bottom of the draw. Draws have a poorly defined channel, and generally do not show evidence of recent flow; 3 Developed to 1) meet desired conditions in the SNFPA-ROD (pg. 43) in order to ensure meadows are hydrologically functional, and species composition and structural diversity of plant and animal communities in meadows provide desired habitat conditions and ecological functions and on 2) Standards and Guidelines in the 1989 ENF Forest Plan (page 4-279) with regard to maintaining the integrity of meadow ecosystems. Within this meadow buffer, hand treatments are allowed but must provide a canopy closure of 60-80%; 4 For special aquatic features other than meadows (springs, seeps, ponds, as measured from the edge of wet area or riparian vegetation, whichever is greater; 5 No entry of mechanical equipment and no reach-in by equipment to remove vegetation. 6 There are two exceptions for the ground-based equipment zones surrounding large meadows: a) aspen treatments near Anderson Canyon, where equipment will be entering the meadow from the direction farthest from Anderson Canyon, and b) Podesta Meadow in Unit 1, where the ground-based equipment exclusion zone surrounding the meadow ranges between 50 and 100 feet; 7 For Podesta Meadow in Unit 1, the canopy closure within 100 feet of the meadow would be in the range of 60-80%; 8 Equipment exclusion zones can be altered on-the-ground for a specific site by a Resource Specialist (Soil Scientist, Fisheries Biologist, Botanist, Hydrologist). 8 Equipment exclusion zones can be altered on-the-ground for a specific site by a Resource Specialist (Soil Scientist, Fisheries Biologist, Botanist, Hydrologist). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

29 Table 6. Additional design features for Aquatic Features and Riparian Conservation Areas (RCAs) of the Foster Firs Project. 1,2,3,4,5,6 Watershed or Unit(s) or Aquatic Feature(s) Riparian Conservation Areas (RCAs) in all Units Design Features Entire RCA Ground cover will be maintained at 70 percent or greater where the ground cover is currently 70 percent or greater. Approval by a Hydrologist, Fisheries Biologist, or Soil Scientist is needed for: a) construction of new landings and/or modification and use of existing landings, b) construction of permanent and/or temporary roads, c) use of ground-based equipment and/or removal of vegetation in inner gorges. Approval by a Hydrologist or Fisheries Biologist is needed for equipment crossings of perennial and intermittent streams or the placement of temporary stream crossing structures. Felling and removal of hazard trees next to haul routes is allowed, with the following restrictions: a) hazard trees with commercial value that can be reached with skidding equipment would be targeted for removal - there will be no endlining to remove trees, b) should a felled hazard tree enter a stream course, the Sale Administrator and Resource Specialist would determine the fate of the tree (e.g. repositioning of the tree, leaving a portion of the tree as felled, etc.), c.) hazard trees with no commercial value and those outside the reach of skidding equipment would be retained in place provided the felled trees would not interfere with the safe use of the road or block culverts in the future. No fire ignition within or immediately adjacent to riparian vegetation, unless otherwise specified for a certain type of aquatic feature. Equipment Exclusion Zones. Reach-in to remove non-riparian vegetation (typically 25 feet) is allowed (but not required) from the edge of the equipment exclusion zone. No end-lining of trees out of equipment exclusion zones. Construction of handlines for fire is allowed. Rehabilitation of the handlines would include waterbars and maintain at least 70 percent ground cover. Stream channels Removal of non-riparian vegetation (living or dead) by hand is allowed up to the edge of the channel so long as the vegetation is not embedded into or growing out of the ground or channel. No removal of woody debris within stream channels or embedded in streambanks. No removal of vegetation (living or dead) within the stream channel or on streambanks. No hand treatments within 25 feet of the edge of perennial stream channels or within riparian vegetation, whichever is greater. No hand treatments within 10 feet of the edge of intermittent stream channels or within riparian vegetation, whichever is greater. Ignition of fire would not occur within 25 feet of the edge of the channel of perennial and intermittent streams and special aquatic features or 25 feet from the edge of riparian vegetation, whichever is greater. Ignition would be limited to non-riparian vegetation. Ignition of fire would not occur within 10 feet of the edge of the channel of ephemeral streams or within 10 feet of riparian vegetation, whichever is greater. Rationale for Design Features Allows for fuel reduction activities near the majority of the aquatic features in the project area, which in turn reduces the risk of a highseverity wildfire in and near these features. Limits the amount of ground disturbance immediately adjacent to these aquatic features, which in turn minimizes the amount of sediment delivered to these features as a result of the Foster Firs Project. Protects inner gorges, where the risk of slope failures is often high and the removal of vegetation and/or ground disturbance greatly increases this risk. Maintains the diversity and cover of riparian vegetation adjacent to aquatic features, while maintaining coarse woody debris in riparian zones and large woody debris in stream channels.

30 Watershed or Unit(s) or Aquatic Feature(s) Design Features No burn piles would be placed within ignition exclusion zones or within 25 feet of any stream channel, whichever is greater. Existing down logs which lie in or across all stream channel types would not be intentionally ignited. Rationale for Design Features Meadow near the end of road 09N95 No ground-based equipment within the RCA of the meadow. This exlcusion does not apply to road work and the decommissioning of roads. The RCA surrounding the meadow is shown in Figure 18. The meadow is degraded and the intent is to greatly reduce the input of runoff and sediment into the meadow from activities associated with the Foster Firs Project. Last 0.4 miles of road 09N95 Removal of two road segments (0.4 miles in total length) at the end of road 09N95 after the completion of the Foster Firs Project. This would involve a) removal of one culvert underneath the road, b) recontouring of the ground surface around the removed culvert, c) hydrologically stabilize the crossing by hardening with cobble or rock, d) ripping of the road surface, e) planting of vegetation, and f) blocking vehicle access to these road segments with large boulders. The location of the two road segments is shown in Figure 18. These two road segments are causing a meadow to not meet Standard &Guideline #100 of the Sierra Nevada Forest Plan Amendment (January 2004). There are two reasons for this: Runoff from the road segments has eroded sediment into the meadow such that the size and/or wetness of the meadow has been reduced. Runoff from the two road segments, as well as the acceleration of streamflow through a culvert underneath one road segment, has caused portions of the stream channel to downcut such that the water table next to the stream has dropped and the size and/or the wetness of the meadow has decreased. 1 The design features in Tables 5 and 6 apply to thinning units and plantations. 2 Riparian Conservation Areas (RCAs) are 300 feet on each side of perennial streams and 150 feet on each side of intermittent and ephemeral streams (SNFPAROD 2004). 3 Protection measures can be altered on-the-ground for a specific site by a Resource Specialist (Soil Scientist, Fisheries Biologist, Botanist, Hydrologist). 4 Draws have poorly defined channels or no visible channel. 5 Inner gorges are defined as areas with slopes greater than 70 percent adjacent to aquatic features. 6 Riparian vegetation is defined as any native plant community composed of species which primarily occur where surface water or a shallow water table are accessible during the summer months and fall. Common, easily recognized riparian species include creek dogwood (Cornus sericea), white alder (Alnus rhombifolia), indian rhubarb (Darmera peltata), chain fern (Woodwardia fimbriata), wild ginger (Asarum lemmonii), columbine (Aquilegia formosa), and common monkey flower (Mimulus guttatus). Non-desirable vegetation targeted for herbicide use generally consists of upland woody brush species such as deer brush (Ceanothus integerrimus), whitethorn (Ceanothus cuneatus), manzanita (Arctostaphylos sp), bearclover (Chamaebatia foliosa), and bitter cherry (Prunus emarginata). A complete list of common riparian plants in California can be found in: Common Riparian Plants of California, a field guide for the Layman (Faber and Holland). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

31 Figure 18. Meadow and Riparian Conservation Area (RCA) near the end of road 09N95. Watershed boundary Skid Trail (30% slope) X Commercial thinning unit RCA Landing " 09N96C Meadow (3.5 acres) 300 ft. 09N96 RCA Road segment proposed for removal (0.4 miles) 09N95B 09N95 Middle Fork Cosumnes River ,000 Feet Miles RCA = Riparian Conservation Area (300 feet surrounding meadows) ² Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

32 CUMULATIVE WATERSHED EFFECTS Method The analysis of cumulative watershed effects (CWE) considers all past, present, and likely future land disturbances in a given drainage area. In the Eldorado National Forest (ENF), the major potential cumulative watershed effect is the degradation of habitat for aquatic and riparian species. This can result when land disturbances - roads, timber harvest, wildfire, etc. - increase the amount of sediment delivered to aquatic features. In the ENF, the risk of the occurrence of CWE for each watershed (HUC 7 scale) is assigned to one of the following four categories: low, moderate, high, or very high. The assignment of the risk of CWE is based on a quantitative evaluation of the land disturbances in the watershed using the method of equivalent roaded acres (ERA). The ERA method is described in more detail in Table 7, and additional background information on CWE is in Appendix A. Land Disturbances A number of land disturbances have occurred or are expected to occur in the three watersheds that contain the Foster Firs Project. Past timber harvest has occurred throughout the project area, which includes a portion of three watersheds at the HUC 7 scale: Anderson Canyon, Upper Middle Fork Cosumnes River, and Podesta. 1 Evidence of past timber harvest includes cut tree stumps and skid trails (Figures 19 and 20). The watersheds are shown in Figure 3. There are approximately 25.6 miles of roads in project area as shown in Figure 3. Metrics with regard to roads are in Table 4. The Foster Firs Project would include a number of activities: a.) commercial and pre-commercial thinning of conifers, b.) prescribed burning, c) restoration activities at selected sites, d) reconstruction and repair of roads, and e.) decommissioning of roads. Two other Forest Service projects are expected to occur in the next few years. The projects are the View 88 Fuels Reduction Project and the Callecat Ecological Restoration Project. Past fire is evident in a small portion of the project area. The Cat Anderson prescribed fire of 2008 burned a total of approximately 1,900 acres on the north side of the Middle Fork Cosumnes River (Markman 2008). This prescribed fire burned approximately 13 percent and 16 percent of the Anderson Canyon and Upper Middle Fork Cosumnes River watersheds, respectively. Camping occurs throughout the project area from June through October, particularly in a large camping area next to Anderson Canyon (Figure 10). 1 Approximately 6.0 acres of the Foster Firs Project may occur in the Upper North Fork Cosumnes River watershed. This is less than 0.8 percent of the watershed, and as a result, has no bearing on the risk of CWE for that watershed..

33 Table 7. Description of the Method of Equivalent Roaded Acres (ERA) for assessing the risk of Cumulative Watershed Effects (CWE). Summary The risk of cumulative watershed effects (CWE) is assessed using the Equivalent Roaded Acre (ERA) method developed by R5 USFS. The process was further refined and adapted for the Eldorado National Forest (1993). In this method, an index is calculated for an entire watershed that expresses most land use in terms of the percent of the watershed covered by roads. Based on the ERA and a threshold of concern (TOC), a given watershed is assigned a relative risk low, moderate, high, or very high - of CWE. The primary cumulative impact of concern is an increase in sediment delivery to streams and degradation of aquatic habitat. Important aspects of the ERA method Roads, which are considered to have the greatest potential to increase runoff and sediment to streams, are given a value of 1.0. The number of acres of roads in a watershed is divided by the size of the entire watershed (in acres). This gives the percent of the watershed covered by roads. For each land disturbance activity other than roads, the number of acres is multiplied by a number less than 1.0. The result (for each land disturbance activity) is then divided by the number of acres of the entire watershed. This gives the percent of the equivalent roaded acres in the watershed for each type of land disturbance. The values for equivalent roaded acres for all of the land disturbance activities are added together. The final number represents the percent of the watershed that is covered by the equivalent of roads. The threshold of concern (TOC) is usually between 10 and 18 percent. That is, when 10 to 18 percent of a watershed is covered by the equivalent of roads, there is a very high risk that increased peak flows of streams and sediment delivery to streams will occur. This does not mean these effects will occur precisely when the ERA reaches the TOC, or that an increase in peak flows and sediment delivery to streams will automatically result in a degradation of fish habitat or diminish the experience of recreationists. It is merely a warning that cumulative effects might occur. Assumptions and limitations of the ERA method The method is intended for watersheds between 3,000 and 10,000 acres in size, although the method is commonly used for watersheds slightly outside of this range. ERA values, as well as the TOC, are only indicators of the risk of cumulative impacts occurring. They cannot be used to determine the percent or numerical amount of increase of sediment delivery to streams, stream channel eroded, fish habitat degraded or lost, or any other change in watershed condition. Such quantitative assessments require additional analysis. The location of land disturbance activities within a watershed is not considered. For example, roads near streams are treated exactly the same as roads that are far from streams. In reality, roads located within or next to riparian areas tend to contribute more sediment to streams than roads in upland areas. Recovery of the watershed from land disturbing activities occurs with time. For timber harvest activities, hydrologic recovery is assumed to be thirty years (i.e. ERA contribution is zero thirty years after timber harvest.) The ERA calculations do not take into account site specific BMPs that will be applied. ERA values start one year after a land use is implemented. Risk categories 1 Low risk of CWE - ERA is less than 50% of TOC Moderate risk of CWE - ERA is between 50% and 80% of TOC High risk of CWE - ERA is between 80% and 100% of TOC Very high risk of CWE - ERA is greater than TOC 1 Guidance for reducing the risk of CWE can be found in Section , Chapter 20 of the Soil and Water Conservation Handbook (USDA 1990). Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

34 Figure 19 (left photo). Skid trail from past logging on the north side of road 09N95. Figure 20 (right photo). Cut tree stump next to a tributary of Anderson Canyon. Results from the ERA method The land disturbances previously described have resulted in the following risk of CWE in the three watersheds that contain the Foster Firs Project. The three watersheds are currently at a low or moderate risk of CWE. If the Foster Firs Project does not occur (Alternative 2 - No Action), the risk of CWE would be low or moderate in the three watersheds until at least If the Foster Firs Project does occur (Alternatives 1, 3, and 4), the risk of CWE would increase to high in the watersheds of Anderson Canyon and Upper Middle Fork Cosumnes River watersheds for two to four years. The risk of CWE would remain low in the Podesta watershed. None of the watersheds would be at a very high risk of CWE. The risk of CWE for the watersheds containing the Foster Firs Project is described in Tables 8 and 9. Equivalent Roaded Acres and the risk of CWE are illustrated in Figures 21 and 22. Equivalent Roaded Acres for individual Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

35 land disturbances in the three watersheds that contain the Foster Firs Project are illustrated in Figure 23. Additional information on CWE is in Appendix A. Conclusions The risk of Cumulative Watershed Effects (CWE) as a result of Alternatives 1, 3, and 4 of the Foster Firs Project is not significant in any of the three watersheds that contain the Foster Firs Project. This conclusion is supported by the results from the model used to assess the risk of CWE. This model indicates that the Foster Firs Project would not cause any of those three watersheds to exceed the Threshold of Concern and would not result in any watershed being at a very high risk of CWE. Table 8. Risk of Cumulative Effects (CWE) of the Foster Firs Forest Heath and Fuels Reduction Project for each watershed and alternative for 2017 through Upper Middle Fork Cosumnes River Anderson Canyon Podesta (#2481) (#2491) (#1311) Alternative 1 (Proposed Action) High High 2017 Alternative 2 (No Action) Alternative 3 Moderate High Low High Low Alternative 4 High High Alternative 1 (Proposed Action) High High 2019 Alternative 2 (No Action) Alternative 3 Moderate High Low High Low Alternative 4 High High Alternative 1 (Proposed Action) High 2021 Alternative 2 (No Action) Alternative 3 Moderate Low Moderate Low Alternative 4 Moderate Alternative 1 (Proposed Action) Moderate 2023 Alternative 2 (No Action) Alternative 3 Moderate Low Moderate Low Alternative 4 Moderate Alternative 1 (Proposed Action) Moderate 2025 Alternative 2 (No Action) Alternative 3 Moderate Low Moderate Low Alternative 4 Moderate Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

36 Table 9. Risk of Cumulative Watershed Effects (CWE) for the Foster Firs Project. Alternative 2 (No Action) means that the Foster Firs Project would not occur. It is assumed that all thinning activities associated with Alternatives 1, 3 and 4 would occur in Equivalent Roaded Acres - percent of the watershed Percent of the Threshold of Concern Risk of Cumulative Watershed Effects Upper Middle Fork Cosumnes River (#2481) Alternatives 1 and 4 Alternative 2 Alternative High Moderate High High Moderate High Moderate Moderate Moderate Moderate Moderate Moderate Moderate Moderate Moderate Alternative High High High Moderate Moderate Anderson Canyon (#2491) Alternative 2 Alternative Low High Low High Low Moderate Low Moderate Low Moderate Alternative High High Moderate Moderate Moderate Alternatives 1 and Low Low Low Low Low Podesta (#1311) Alternative Low Alternative Low Low Low Low Low Foster Firs Forest Health and Fuels Reduction Project draft Hydrology Report

37 Equivalent Roaded Acres - percent of the Threshold of Concern (TOC) Figure 21. Equivalent Roaded Acres (ERA) - expressed as a percent of the Threshold of Concern (TOC) - for the Foster Firs Project in Very high risk of CWE % TOC in Alternative 2 (No Action) %TOC in Alternative 1 (Proposed Action) %TOC in Alternative 3 %TOC in Alternative High risk of CWE ` Moderate risk of CWE Low risk of CWE Upper Middle Fork Cosumnes River Anderson Canyon Podesta 1 The year 2017 represents the highest level of ERA as a result of the Foster Firs Project.

38 Equivalent Roaded Acres - percent of the Threshold of Concern (TOC) Figure 22. Equivalent Roaded Acres (ERA) - expressed as a percent of the Threshold of Concern (TOC) - for the Foster Firs Project in Very high risk of CWE % TOC in Alternative 2 (No Action) % TOC in Alternative 1 (Proposed Action) % TOC in Alternative 3 % TOC in Alternative High risk of CWE Moderate risk of CWE Low risk of CWE Upper Middle Fork Cosumnes River Anderson Canyon Podesta 1 The year 2017 represents the highest level of ERA as a result of the Foster Firs Project, and the year 2021 is four years after the highest level of ERA.

39 Upper Middle Fork Cosumnes River Anderson Canyon Podesta Figure 23. Percent Equivalent Roaded Acres (% ERA) in 2017 for individual land disturbances as a result of Alternative 1 (Proposed Action) in the three watersheds that contain the Foster Firs project. 1,2 % ERA in 2017 from other future timber harvest % ERA in 2017 from grazing % ERA in 2017 from past fire % ERA from misc. impervious areas % ERA from roads % ERA in 2017 from past timber harvest % ERA in 2017 from Foster Firs Percent Equivalent Roaded Acres (ERA) 1 The year 2017 represents the highest level of ERA as a result of the Foster Firs Project. 2 The ERA for Alternatives 3 and 4 are similar to Alternative 1 for the three watersheds that contain the Foster Firs Project.

40 REFERENCES CITED Beche, Leah A., Scott L. Stephens, and Vincent H Resh Effects of prescribed fire on a Sierra Nevada stream and its riparian zone. Forest Ecology and Management, Volume 218, Issues 1-2, October 24, 2005, pages Busse, et. al Effects of pile burning in the Lake Tahoe Basin on soil and water quality. Lake Tahoe Basin Management Unit, Lake Tahoe, California. Unpublished. Cafferata, Peter Temperature regimes of small streams along the Mendocino coast. Jackson Demonstration State Forest, State Department of Forestry, P. O. Box 1185, Fort Bragg, California Newsletter No. 39, October. CVRWQCB (Central Valley Regional Water Quality Control Board) Internet Site containing the proposed 303(d) list for the central valley region of California CVRWQCB (Central Valley Regional Water Quality Control Board) Internet site containing Basin Plan for the Central Valley Region. Dissmeyer, George, E, editor Drinking Water from Forest and Grasslands: A Synthesis of the Scientific Literaure. United States Department of Agriculture, Forest Service. General Technical Report SRS-39. Eldorado National Forest Cumulative Off-site Watershed Effects (CWE) Analysis Process. Version 1.1 Faber, Phyllis M. and Robert F. Holland Common Riparian Plants of California, a Field Guide for the Layman. Pickleweed Press. 212 Del Casa, Mill Valley, California ISBN LABAT (Labat-Anderson Incorporated) Residues of Fire Accelerant Chemicals Westpark Drive, Suite 400, McLean, Virginia, Prepared for: USDA Forest Service, Intermountain Region, Ogden, Utah. MacDonald, Lee H Evaluating and Managing Cumulative Effects: Process and Constraints. Environmental Management, Volume 26, No. 3, pp MacDonald, Lee H, and John D. Stednick Forests and water: a state-of-the-art review for Colorado. Colorado State University, Colorado Water Resources Research Institue Completion Report No pages. Can be downloaded from the internet at Markman, Steve, G Cat Anderson Prescribed Fire, Hydrology Report. Amador District Office, Eldorado National Forest. Nicita, Eric Soils Report for the Foster Firs Forest Health and Fuels Reduction Project. Eldorado National Forest, Supervisors Office. 100 Forni Road, Placerville, CA Parkyn, Stepanie Review of riparian buffer zone effectiveness. Ministry of Agriculture and Forestry Technical Paper No. 2004/05. ISBN No ISSN No Reid, Leslie M Research and cumulative watershed effects. General Technical Report PSW-GTR-141. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; 118 p. Reid, Leslie M. and Sue Hilton Buffering the buffer. USDA Forest Service General Technical Report, PSW-GTR-168. Robichaud, P.R. and R.E. Brown What happened after the smoke clear: onsite erosion rate after a wildfire in Eastern Oregon. Revised (November 2000) In: Olsen, D.S., and J. P. Potyondy (editors). Proceedings AWRA Specialty Conference: Wildland Hydrology, Bozeman, MT

41 Shaw, E.A. and J.S. Richardson Direct and indirect effects of sediment pulse duration steam invertebrate assemblages and rainbow trout (Oncorhynchus mykiss) growth and survival. Canadian Journal of Fish and Aquatic Science. 58: 2213:2221. Sierra Nevada Ecosystem Project, Final Report to Congress, vol. III Davis: University of California, Centers for Water and Wildland Resources. ISBN USDA Forest Service Soil and Water Conservation Handbook, Region 5. Section , Chapter 20. Cumulative off-site watershed effects analysis. USDA Forest Service. May Forest Roads: A Synthesis of Scientific Information. General Technical Report PNW-GTR-509. USDA Forest Service Middle Fork Cosumnes River watershed, landscape, and roads analysis. Eldorado National Forest, Supervisors Office. 100 Forni Road, Placerville, California USDA Forest Service. January Sierra Nevada Forest Plan Amendment, Final Environmental Impact Statement, Record of Decision. USDA Forest Service Cumulative Watershed Effects of Fuel Management in the Western United States. General Technical Report RMRS-GTR-231. USDA Forest Service. December Water Quality Management for Forest System Lands in California, Best Management Practices. Pacific Southwest Region USDA Forest Service. March Water Quality Protection on National Forest in the Pacific Southwest Region: Best Management Practices Evaluation Program, United States Geological Survey (USGS) Program that calculates basin and streamflow characteristics, found on the internet at: Wilkinson, Kathryn. Biological Assessment/Evaluation for the Foster Firs Forest Health and Fuels Reduction Project. Eldorado National Forest, Supervisors Office. 100 Forni Road, Placerville, CA Wright, et. al and Others Effect of Prescribed Burning on Sediment, Water Yield, and Water Quality from Juniper Lands in Central Texas. Journal of Range Management, Volume 29, No. 4. July 1976, pages

42 GLOSSARY best management practice (BMP) A practice or practices that is the most effective and practical means of preventing or reducing the amount of pollution generated by nonpoint sources. BMPs are contained in Water Quality Management for Forest System Land in California, USDA Forest Service, September 2000 the BMPs have been approved by the California Water Quality Control Board under the jurisdiction of Section 208 of the Clean Water Act (PL ). beneficial uses of water State law defines the beneficial use(s) of bodies of water. In California, the beneficial uses of a particular body of water may include one or more of the following: domestic; municipal; agricultural and industrial supply; power generation; recreation; aesthetic enjoyment; navigation; preservation and enhancement of fish, wildlife, and other aquatic resources or preserves. cumulative watershed effects (CWE) All effects on the beneficial uses of water that occur away from the location of actual land use which are transmitted through the fluvial system. cumulative impact the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-federal) or person undertakes other such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. (NEPA, ) draw A land feature that resembles a stream in some respects, but has a poorly defined channel and shows little or no evidence features that are characteristic of flowing water. Surface flow can occur during rainfall events of high intensity. Draws can develop into streams over geologic time if the climate becomes wetter. ephemeral streams have a defined channel throughout much, but not necessarily all of their length. Surface flow exists only during and for a short time following precipitation events. There is little or no riparian vegetation. Nonriparian vegetation, including conifers, may be found on the streambanks and even in the streambeds. Rocks in the channel are generally not covered with green moss. The ephemeral stream layer in GIS of the Eldorado Natioanal Forest typically shows more ephemeral streams than actually exist on-the-ground - some ephemeral streams in GIS are actually draws or swales. equivalent roaded acre (ERA) A method of categorizing the amount of soil compaction from land management activities into the common base of a compacted road surface. Roads are assigned an ERA value of 1.0; all other disturbed areas are assigned ERA values less than or equal to one. intermittent or seasonal stream have a well-defined channel throughout the entire length of the stream. Surface flow exists part of the year and may exist most of the year, but not year-round. There is usually some riparian vegetation adjacent to the channel. Green moss on rocks in the channel and adjacent to the channel is often an indicator that a stream is seasonal, not ephemeral. perennial streams have a well-defined channel throughout the entire length of the stream. Surface flow exists year-round. Riparian vegetation is usually dominant adjacent to the channel, although non-riparian vegetation may also exist. threshold of concern (TOC) The point where there a concern that cumulative watershed effects are at a high risk of occurring.

43 APPENDIX A. HYDROLOGIC INFORMATION for the FOSTER FIRS FOREST HEALTH AND FUELS REDUCTION PROJECT. 1. Water Quality. a. California water quality standards and objectives. b. Beneficial uses of water. c. Water bodies on the 303(d) list. d. Temperature of several perennial streams. e. Nutrients and prescribed fire. 2. Ground disturbance in Riparian Conservation Areas (RCAs). 3. Maps of roads and stream crossings of roads by alternative. 4. Cumulative Watershed Effects. a. Background. b. Land disturbances by watershed. 5. Geologic map of the Foster Firs Project area. 6. Additional photographs in the Foster Firs Project area.

44 1. Water Quality Foster Firs Project. a. California water quality standards and objectives. Assessment of water quality standards and objectives designated by the Central Valley Regional Water Quality Control Board. 1,2 Parameter Narrative standard Numerical Standard Assessment as a result of the Foster Firs Project Sediment Turbidity The suspended sediment load and suspended sediment discharge rate of surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. No numerical standards. Increases in turbidity attributable to controllable water quality factors shall not exceed 20 percent where the natural turbidity is between 0 and 50 Nephelometric Turbidity Units (NTU). Increases in turbidity and suspended sediment levels of streams in the project area are expected to be minor or negligible. The reasons for this conclusion are described in the section Direct and Indirect Effects. Temperature The natural receiving water temperature shall not be altered unless it can be demonstrated to the satisfaction of the water board that such alteration does not adversely affect beneficial uses. At no time or place shall the temperature of COLD waters be increased more than 5 o F above natural receiving water temperature. Increases in temperature to the perennial streams in the project area are expected to be negligible or minor. The reasons for this conclusion are described in the section Direct and Indirect Effects. 1 The Clean Water Act gives the states the authority to set water quality standards. The standards set by the states apply to the National Forest, and the Eldorado National Forest is under the jurisdiction of the Central Valley Regional Quality Control Board (CVRWQCB). 2 The water quality standards in this table are from the following document: The Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control board, Central Valley Region, Fourth Edition, September 15, This document can be found on the internet at

45 b. Beneficial Uses of Water. The Clean Water Act (1972) gives each state the authority to set water quality standards and designate beneficial uses of water on all lands within that state. The Eldorado National Forest is under the jurisdiction of the Central Valley Regional Quality Control Board (CVRWQCB) of California. The Foster Firs Project includes a small portion of the headwaters of the drainage basin of the Cosumnes River and the Mokelumne River. The beneficial uses of the drainage basin are listed in Table A2b-1. The Foster Firs Project will protect all of the designated beneficial uses of water in this drainage basin. The major reasons for this conclusion are summarized below. The Foster Firs Project is not located near a reservoir, and therefore, not near a municipal source of drinking water. Increases in the delivery of sediment to aquatic features within and downstream of the project area as a result of the Foster Firs Project are expected to be minor or negligible. As a result, a) state water quality and standards for turbidity and suspended sediment of streams will not be exceeded, and b) aquatic habitat will not be adversely affected. Changes to the water yield, peak flow, and timing of flow of all streams in the project area and downstream are likely to be negligible and not measurable. Increases to stream temperatures will be minor or negligible.

46 Hydro Unit Number Municipal and domestic supply Irrigation Stock Watering Process Service Supply Power Contact Canoeing and rafting (1) Other Non-contact Warm Cold Warm (3) Cold (4) Warm (3) Cold (4) Wildlife habitat Navigation Table A2b-1. Beneficial uses of water in the drainage basin that contains the Foster Firs Project (CRWQCB 1998). MUN AGRIGULTURE INDUSTRY RECREATION FRESHWATER HABITAT (2) MIGRATION SPAWNING WILD NAV AGR PROC IND POW REC-1 REC-2 Warm Cold MIGR SPWN Cosumnes River - sources to Nashville Reservoir Mokelumne River sources to Pardee Reservoir 532. E E E E E E E E E E E E E E E E E E E = existing P = Potential Footnotes 1 Shown for streams and rivers only with the implication that certain flows are required for this beneficial use. 2 Resident does not include anadromous. Any segments with both COLD and WARM beneficial use designations will be considered COLD water bodies for the application of water quality objectives. 3 Stiped bass, sturgeon, and shad. 4 Salmon and steelhead.

47 Table A2b-2. Effects to Beneficial Uses of Water as a result of the Foster Firs Project. Beneficial use(s) Protected Likely effects as a result of the Foster Firs Project Municipal and domestic water supply Hydropower generation (POW) Contact recreation; Canoeing and rafting; Non-contact recreation; (REC-1 and REC-2) Yes Yes Yes A minor increase in the suspended sediment concentrations and turbidity levels of streams that occur in the Foster Firs Project is possible during and immediately after large rainfall events and periods of rapid snowmelt. This increase should it occur should not exceed state water quality standards for turbidity or sediment. The reasons for this conclusion are described in detail in the section Direct and Indirect Effects. Changes to the water yield, peak flow, and timing of flow of all streams in the project area and downstream are likely to be negligible and not measurable. The research indicates that fuels reduction treatments in forested watersheds have little detectable impact on water yields either on-site or downstream. Most prescriptions are not likely to remove the 20 percent of the basal area that is needed in most areas to generate a detectable change in flow. (USDA 2010). The Foster Firs Project would have a negligible effect on the amount of water in streams and the water quality of streams. The reasons for this conclusion are described in detail in the section Direct and Indirect Effects. Freshwater habitat, warm and cold; Spawning habitat, warm and cold; Wildlife habitat Yes The Foster Firs Project would have a minor or negligible effect on the habitat for fish and amphibians both within and downstream of the project area. The reasons for this conclusion are described in detail in the Biological Assessment/Evaluation for the Foster Firs Project. c. Water bodies on the 303(d) list. The Foster Firs Project is located in a portion of the headwaters of the Cosumnes River drainage basin. The entire Cosumnes River (35 miles) is on the 303(d) list for exotic species. The Foster Firs Project has no influence on the presence or spread of any aquatic species in the Cosumnes River. The primary reason is that the Foster Firs Project does not involve the introduction, redistribution, or feeding of any aquatic species. Section 303(d) of the Clean Water Act of 1972 requires each state to identify water bodies that fail to meet applicable water quality standards (CVRWQCB 2015). The U.S. Environmental Protection Agency (EPA) approves the final 303(d) list from each state.

48 d. Temperature of several perennial streams in the Foster Firs Project. The equation below is from Cafferata (1990) 1 Description of the variables used to predict the maximum stream temperature increase Temperature Increase Length Width Percent Heat Conversion Discharge Maximum increase in temperature as a result of the loss of shade on the stream surface. Length of flowing stream impacted by removal of vegetation. Average stream width. Percent shade lost (shade before removal of vegetation minus shade after removal of vegetation). Heat input, based on latitude, time of the year, and travel time of water to pass through the length of the stream impacted by the removal of vegetation. Conversion factor of for units of feet, cubic feet per second, degrees Fahrenheit. Discharge of the stream, cubic feet per second. Temperature Increase = Length x Width x Percent x Heat x Conversion Discharge Assumptions used: A reduction of canopy cover (from the Foster Firs Project) of 13 percent (average value in the RCA) translates to a reduction in shade to the surface of the stream of approximately 5 percent. This is an estimate, based on observations that much of the shade on the surface streams in the project area is from riparian vegetation next to the stream (the narrow width of the stream channels allow riparian vegetation to shade a portion of the stream), and that this riparian vegetation will not be removed. No correction factor for shade from topography (e.g. north-facing slopes vs. south-facing slopes, shade from incised canyon, etc.). Time of the year is mid-to-late summer. The flows of the tributaries are based on visual estimates.

49 Maximum potential stream temperature increases Length (ft.) Width (ft.) Percent Heat (BTU/ft. 2 - min.) Conversion Discharge (cfs.) Temperature change ( 0 F) Anderson Canyon 3, Middle Fork Cosumnes River Cafferata, Peter Temperature regimes of small streams along the Mendocino coast. Jackson Demonstration State Forest, State Department of Forestry, P. O. Box 1185, Fort Bragg, California Newsletter No. 39, October.

50 e. Nutrients and prescribed fire. 1.) There is a considerable amount of published research concerning the effects of large wildfires on water quality. There is less published research concerning the effects of prescribed fire on water quality. For both wildfires and prescribed fire, there is far less research concerning the effects on aquatic habitat and aquatic species than water quality (MacDonald and Stednick 2003). Few studies have been conducted on the effects of prescribed fire on water quality, aquatic species, and riparian areas in the western United States (Beche and others 2005). 2.) The available research indicates that prescribed fires have relatively minor effects to water quality when compared to large wildfires. The two primary reasons for this are: Prescribed fires are usually conducted on areas that are much smaller in size than large wildfires. It is not uncommon for a large wildfire to burn thousands of acres and a large portion of an entire watershed or large portions of a number of watersheds. Prescribed fires are designed to burn at lower intensities than large wildfires. As a result, a prescribed fire typically consumes far less vegetation and ground cover than a large wildfire and is less likely to result in large areas of hydrophobic soils.. This usually translates to far less runoff, erosion, and sediment delivery to aquatic features than from a large wildfire (MacDonald and Stednick 2003; Dissmeyer 2000; Beche and others 2005). 1 3.) The published research indicates that the effects to water quality from prescribed fire are usually quite small when vegetated buffer strips are left next to streams (MacDonald and Stednick 2003). 4.) The published research indicates that effects to water quality and aquatic species from prescribed fire - when such effects do occur - are relatively short-lived and last only a few years (MacDonald and Stednick 2003; Dissmeyer 2000; Beche and others 2005). 5.) The slopes next to a stream can be an important factor that influences the increase in sediment delivery to a stream and the resulting suspended sediment/turbidity levels of a stream after a prescribed fire. In one welldocumented and frequently cited research study in central Texas, there was no increase in the turbidity of streams on slopes less than 5 percent and a one order-of-magnitude increase in the turbidity of streams for slopes between 37 and 61 percent for one year after a prescribed fire (Wright and others, 1976). 2,3 6.) There is little published research concerning the effects to water quality and aquatic species from the materials and chemical residues that are produced from prescribed fire ignition; on-the-ground monitoring of effects is generally lacking. 4,5 However, one detailed risk assessment concluded that: a.) there is no risk to general aquatic species and, b.) there may be a slight risk to sensitive aquatic species under certain conditions (LABAT 2002). 6 7.) There is little published research concerning the effects to water quality from the burning of piles of slash. However, one unpublished study in the Lake Tahoe Basin found that concentrations of nitrate, orthophosphate, and sulfate approximately seven meters downslope of bun piles were generally less than 8.0 milligrams per liter ( Busse, et. al. 2011). The Federal recommended maximum contaminant level (MCL) for nitrate is 10.0 milligrams per liter. 1 Erosion, sediment delivery to streams, and effects to water quality and aquatic habitat following wildfires is highly variable from site to site and depends on a number of factors. Detailed studies on the Bobcat Fire near Fort Collins, Colorado showed that sites burned at high severity produced 10 to 30 times more sediment than unburned or lightly burned sites (MacDonald and Stednick 2003). 2 The study was conducted in an oak-juniper woodland on soils derived from limestone. In addition, the drainage areas were very small (0.066 to acres) and buffer strips of unburned vegetation were not left next to streams. The results of this study may not apply to areas with different characteristics. 3 Turbidity is a numerical measure of the clarity of water and a general indicator of the amount of suspended sediment in water. 4 This statement is based on a diligent search of published research articles on the internet. 5 The commonly-used methods of prescribed fire ignition are: fusee, drip torch, tera-torch, propane wand, flares, heli-torch, and synthetic combustible spheres. 6 A slight risk to aquatic species might occur under one or more of the following conditions: a.) small streams (flow of less than 12 cubic feet per second), b.) steep slopes next to the stream, c.) un-vegetated areas next to the stream, d.) high rates of precipitation, and e.) impermeable soils (LABAT 2002).

51 Stream Total length (feet) Stream length bordering Units within RCA (feet) Percent of stream length bordering Units (within RCA) Total width of RCA (feet) Size of entire RCA (acres) Size of RCA in Units (acres) Percent of RCA with ground-based equipment (in Units) Size of RCA in Units with groundbased equip-ment (acres) Skid trail spacing (feet) Skid trail width (feet) Number of skid trails in RCA Area of skid trails in RCA (sq. ft.) Area of skid trails in RCA (acres) Num-ber of land-ings in RCA Total area of landings in RCA (acres) Area of skid trails + landings in RCA (acres) Percent of ground disturbance in entire RCA 2. Ground disturbance in Riparian Conservation Areas (RCAs). Ground-disturbing activities would occur in a relatively small percentage of the Riparian Conservation Areas (RCAs) next to streams. (The RCA is 300 feet on each side of perennial streams and 150 feet on each side of intermittent and ephemeral streams). The calculations of ground-disturbing activities in the RCAs of these streams consider: The number of acres of RCA both within and outside of commercial harvest units. The width of the equipment exclusion zone adjacent to the streams within the commercial harvest units. Estimates of the amount of ground-disturbing activities within the zone of ground-based equipment. The definition of ground-disturbing activities as contained in the SNFPA of 2004: Activities that result in detrimental soil compaction or loss of organic matter beyond the thresholds identified by soil quality standards. This incudes, but may not be limited to: landings, skid trails, and temporary roads. Grounddisturbing activities and soil quality standards are discussed detail in the Soils Report. The calculations of ground-disturbing activities for individual streams are shown below. Anderson Canyon Middle Fork Cosumnes River AN AN AN AN

52 3. Maps of roads and stream crossings of roads by alternative. (Note: These maps do not indicate which roads are open or closed to public use. Please consult the description of the Alternatives in the Environmental Assessment for proposed changes to the Motor Vehicle Use Map.) Alternative 2 (No Action) 10N50 09N67 09N02B 09N02A 09N02 09NY11 09NY11A 09N14 09N14B 09N14C 09N14D 09N68A 09N68 Perennial stream Intermittent stream 09N14K AN4 AN3 AN2 09N14M AN1 Ephemeral stream Anderson Canyon 09N14 NSR 09N68 09N95 09N96C Location where a road crosses a stream NSR 09N95B 09N95 09N14L Middle Fork Cosumnes River Road Miles ² 09N14 09N14 09N96A 09N96 0 1,000 2,000 4,000 Feet

53 Alternative 1 (Proposed Action) and Alternative 4. 10N50 09N67 09N02B 09N02A 09N02 09NY11 09NY11A 09N14K 09N14 09N14B 09N14C 09N68A 09N68 Perennial stream Intermittent stream AN4 AN3 AN2 09N14M AN1 Ephemeral stream Anderson Canyon 09N68 09N96C 09N14 Location where a road crosses a stream Middle Fork Cosumnes River 09N95B 09N95 Road Miles ² 09N14 09N14 09N96A 09N96 0 1,000 2,000 4,000 Feet

54 Alternative 3 10N50 09N67 09N02A 09N02 09N14 09N68 Perennial stream AN4 AN3 09N14K AN2 09N14M AN1 Intermittent stream Ephemeral stream Anderson Canyon 09N68 09N96C 09N14 Location where a road crosses a stream Middle Fork Cosumnes River Road Miles ² 09N14 09N14 09N96 0 1,000 2,000 4,000 Feet

55 4. Cumulative Watershed Effects Foster Firs Project. a. Background. Definition of CWE Geographic scope of CWE Methods and limitations of assessing CWE The analysis of cumulative watershed effects (CWE) considers the impacts of all past, present, and foreseeable land disturbances. The land disturbances selected for the analysis of CWE include those that have the potential to result in erosion and an increase in sediment delivery to aquatic features. These land disturbances include, but are not limited to: past timber harvest (both in the National Forest and on private land), roads, fires, man-made impervious areas associated with buildings and other facilities, powerline corridors, and campgrounds. An increase in the amount of sediment delivered to aquatic features can result in a number of negative effects. 1 The HUC 7 watersheds, which are generally 3,000 to 10,000 in size, which include the proposed land disturbance or changes in land disturbance. Sub-watersheds less than 3,000 acres in size may be delineated for analysis if land disturbances are concentrated in those areas. There are a number of methods currently used to assess CWE where the primary direct impact of concern is an increase in sediment delivery to streams and other aquatic features. None of these methods can quantitatively predict the amount of sediment delivered to streams, the distance downstream that the sediment load will travel, or point in time and the duration when an increase in sediment delivery to aquatic features will occur. The reasons for this include the large variability in the magnitude of direct effects from a given land disturbance, inability to predict secondary or indirect effects, lack of data on recovery rates for land disturbances, difficulty of validating predictive models on-the-ground, and the uncertainty of future events such as the size and timing of large storms. As a result, an assessment of CWE is frequently reported as an indicator of the overall risk of cumulative effects occurring in a watershed (Reid 1993; MacDonald 2000). Magnitude or severity of CWE The magnitude or severity of CWE following land disturbance depends largely on an event that cannot be prevented and the exact timing of which cannot be accurately predicted. It is whether a large storm event occurs within several years after land disturbances when the ground surface is vulnerable to erosion. If a large storm event does not occur within several after the land disturbance, the CWE to aquatic features will be minor, negligible, or absent. As a result of the importance of large storm events in determining actual erosion, sediment delivery to streams, turbidity and suspended sediment levels of streams, the land disturbances themselves in the watersheds play only a partial role in the severity of impacts to aquatic resources. Method of CWE used in the Eldorado National Forest The method selected for this CWE analysis is the method of Equivalent Roaded Acres (ERA). This method was developed by Region 5 of the U.S. Forest Service and adapted by the Eldorado National Forest (ENF). The method was specifically developed to assess the risk of CWE in forested watersheds where timber harvest and roads are major land disturbances. The ERA method has been used in the ENF for over 15 years, and nearly all of the 155 watersheds in the ENF have been evaluated with this method. This allows all of the watersheds in the ENF to be compared relative to each other in terms of the risk of CWE. Description of the method of Equivalent Roaded Acres (ERA) An index is calculated for an entire watershed that expresses most land uses in terms of the percent of the watershed covered by roads. Based on the percent ERA and a threshold of concern (TOC), a given watershed is assigned a relative risk low, moderate, high, or very high - of cumulative impacts. A very high risk is merely a warning that cumulative impacts such as an increase in sediment delivery to streams might occur. The ERA method has the same limitations as previously described for all commonly used CWE methods where an increase in sediment delivery to streams is the primary concern. 1 One well-documented cumulative effect is the reduction in the amount and quality of spawning habitat for resident fish as a result of fine-grained sediment deposited in the stream channel.

56 Potential cumulative effects to aquatic resources Primary Effects 1. Increase in the peak flows of streams. 2. Increase in the amount of sediment delivered to streams. Mostly likely time period of occurrence During and immediately after large precipitation events and periods of rapid snowmelt. Secondary effects 1. Erosion of stream channels. Amount of erosion depends on: a) size and duration of peak flow, b) inherent stability of channel. (Alluvial channels erode more than those controlled by bedrock.) 2. Increase in the turbidity of streams. This can affect the health of fish, affecting movement and feeding. 3. Alteration of fish habitat. Removal of cover (large woody debris, overhanging banks, rocks). Covering of spawning areas with fine-grained material. Reduction in stream channel diversity. Examples: pools filled in with alluvial material, removal of large woody debris. 1. Increase in the turbidity of streams. This can affect the health of fish, possibly resulting in death. 2. Alteration of fish habitat. Pools fill in with alluvial material. Spawning areas are covered with fine-grained sediment. Beneficial stream uses that are affected 1. Fisheries. Impacts to fish are described under secondary impacts. 2. Recreation. Adverse impacts to fish diminish fishing opportunities. Eroded stream channels are less aesthetically pleasing to people that come to streams to recreate. 1. Fisheries. Impacts to fish are described under secondary impacts. 2. Recreation. Streams with turbid water are less aesthetically pleasing to most people than streams with clear water.

57 b. Land disturbances by watershed. The equivalent roaded acres (ERA) and the on-the-ground effects of each past and present individual activity (i.e. each individual past timber sale, each existing and past road, each present and past impervious area, each fire, each flood event, etc.) is not presented here. The primary reason for this is that the science simply does not exist to accurately and precisely determine the effect of each individual prior human action and each past natural event in the watershed on the current condition of a single aquatic feature or a group of aquatic features. The existing condition of each aquatic feature is the result of the aggregate impact of many prior human actions and natural events in the entire watershed over a long period of time. The existing condition of individual aquatic features in the project area is described in detail in the section Affected Environment and Existing Conditions. The overall risk of cumulative watershed effects (CWE) for each watershed that contains the Foster Firs Project, as well as the method of assessing that risk, is described in the section Cumulative Watershed Effects. The next page list the equivalent roaded acres (ERA) and the percent ERA for each type of known past and reasonably foreseeable land distances in 2017 for each HUC 7 watershed that contains the Foster Firs Project. The major land disturbances have been previously described in the section Cumulative Watershed Effects.

58 Table A4-a. Eqivalent Roaded Acres (ERA) in 2017 for individual land disturbances in each watershed (HUC 7 scale) that contains the Foster Firs Project for Alternative 1 (Proposed Action). 1,2,3,4 Upper Middle Fork Cosumnes River # acres Anderson Canyon # acres Podesta # acres Foster Firs Project Past timber harvest Roads Equivalent Roaded Acres (ERA) in 2017 Misc. impervious areas Fire Grazing Other future timber harvest Foster Firs Project Past timber harvest Equivalent Roaded Acres (ERA) in 2017 expressed as a percent of the watershed Roads Misc. impervious areas Fire Grazing Other future timber harvest Values for Alternatives 3 and 4 are either the same or similar to Alternative 1. 2 Values for the Foster Firs Project includes all activities that would occur as a result of the project. The peak ERA from the Foster Firs Project would occur in 2017, assuming that all thinning activities occur in Values for timber harvest include the Eldorado National Forest and private land. 4 ERA from past fire does not include prescribed fire from the Foster Firs Project.

59 5. Geologic map of the Foster Firs project area. 1 09N14 09N14A 10N50 09N02 09N67 09N02B 09N02A 09N02 09NY11A 09N14 09N14B Tm 09N14C 09N14D 09N68A 09N68 09NY11 AN4 09N14K AN3 AN2 09N14M Qal AN1 09N96 ² Anderson Canyon 09N14 09N95 09N96C KJgr 09N68 09N95B 09N95 09N14L Tm Middle Fork Cosumnes 09N14 09N96A 09N14H River 09N14 09N96 Qal Alluvium Perennial stream Intermittent stream Tm Volcanics of the Mehrten Formation Thinng areas of the Foster Firs Project Miles KJgr Granitic rocks 0 1,250 2,500 5,000 Feet 1 The Environmental Assessment contains detailed maps of the thinning areas of the Foster Firs Project. The roads in this map depict the roads as shown in GIS and may not exactly correspond to the location and lengths of roads on-the-ground. Consult the current Motor Vehicle Use Map (MVUM) for roads open to the Public.

60 6. Additional photographs in the Foster Firs project area. A segment of the lower portion of Anderson Canyon flows over granitic bedrock. Sand and gravel deposits in the segment of lower Anderson Canyon that flows over bedrock.

61 Ephemeral stream that flows into Anderson Canyon near Unit 10. Intermittent stream in Unit 10 of the Foster Firs Project. The stream flows into Anderson Canyon.

62 Middle Fork Cosumnes River, approximately 0.5 miles upstream of where road 09N14 crosses the stream. A portion of the meadow at Podesta Camp, Podesta watershed, just south of road 09N68.

63 A segment of the intermittent stream just to the north of the meadow at Podesta Camp, Podesta watershed, just south of road 09N68. Podesta Camp Spring in the Podesta watershed, south of road 09N68.

64 Granitic rocks and shallow soils derived from granitic rocks on the north side of Anderson Canyon. Forest and fuels on the floor of the forest on the north side of road 09N95.