Hydrology Report
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Giant Sequoia National Monument Specialist Report Signature: __________________________________________ Date: _______________________________________________ The U. S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, or marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964 (voice and TDD). USDA is an equal opportunity provider and employer. Contents HYDROLOGY REPORT INTRODUCTION 2 AFFECTED ENVIRONMENT 2 ENVIRONMENTAL EFFECTS 147 Legal and Regulatory Compliance 172 Cumulative Effects 173 LITERATURE CITED AND REFERENCES 190 APPENDIX A 192 APPENDIX B 209 APPENDIX C 237 APPENDIX D 241 APPENDIX E 245 Hydrology Report GSNM Specialist Report Hydrology Report Introduction Terry Kaplan-Henry – Forest Hydrologist Joshua Courter – District Hydrologist The hydrology report for the Giant Sequoia National Monument (Monument) is organized by Affected Environment, Environmental Effects, Management Strategy, and References. The Affected Environment provides information on Stream Condition Inventory (Frazer et al. 2005), Riparian Ecotypes (Kaplan-Henry 2000), existing uses, past fires, and macroinvertebrate data. The Affected Environment is organized in a hierarchal manner using 4th field watersheds as the largest unit. Smaller field watersheds are nested within the 4th field watersheds. Information on 5th and 7th-field watersheds is provided under the main 4th-field HUC (1) For example, the Upper Tule River basin (4th-field HUC watershed), contains three 5th-field HUC watersheds: North Fork, South Fork, and Middle Fork of the Tule River. These 5th-field HUC watersheds are further subdivided into 6th-field HUC watersheds, which are divided further into 7th-field HUC watersheds. The hydrology report provides an introduction to the location, general characteristics, special watershed basin conditions, and summary of information found in smaller HUCs within the 4th-field HUC watershed description. The 5th field HUC watershed description goes into more detail surrounding watershed characteristics and studies/surveys that have occurred in the 7th-field HUC. The 7th-field HUC provides site specific detailed information to individual streams and the results of inventories and studies. There is no information provided at the 6th-field HUC watershed scale in the Affected Environment. The 6th-field HUC watershed is used as a planning tool for the Cumulative Watershed Effects Analysis in the Effects of Alternatives. Affected Environment An analysis has been performed for the watersheds associated with the Monument. The analysis complies with management direction in the 2001 and 2004 Sierra Nevada Forest Plan Amendments (SNFPA) and provides direction to define existing conditions (USDA Forest Service 2001, 2004). Watershed analysis provides a beginning point for more refined landscape analysis, which will assist the forest in identification of new projects. Additionally, landscape analysis provides the basis for adjustment of the SNFPA Riparian Conservation Objectives (RCOs) and are commensurate with local conditions in Monument watersheds. The watershed/landscape nested analysis provides science-based information regarding the existing condition of watershed level ecosystems as well as the impacts of past, current, and reasonably foreseeable future management activities. The following descriptions provide characterization of the watersheds affected by the Giant Sequoia National Monument plan. The California State Water Resources Control Board, U.S. Department of Agriculture, U.S. Environmental Protection Agency, and the U.S. Department of Agriculture, Natural Resources Conservation Service conducted a Unified Watershed Assessment (UWA) in accordance with the Federal Clean Water Action Plan (CWAP) (US Environmental Protection Agency 1998). The purpose of the UWA was to identify those watersheds with the most critical water quality needs and to help guide resources toward correcting identified 1 Hydrologic Unit Codes (HUCs) were designated by the United States Geological Service (USGS) in conjunction with other agency input, HUCs are used as a standardized watershed classification system. GSNM Specialist Report Hydrology Report 2 Hydrology Report problems. The information from this analysis has been incorporated into the Watershed Analysis for the Monument’s watersheds. The Unified Watershed Assessment was performed at the Basin or 4th-field Hydrologic Unit Classification (HUC 4 watershed) level. Watershed Assessments for watersheds associated with the Monument have been done at the HUC 5 watershed scale. Information used to characterize watersheds includes data collected at all levels. The intent of including more detailed information is to facilitate landscape analysis. The Sierra Nevada Forest Plan Amendment Record of Decision (2001 and 2004 SNFPA ROD) provides the directive for the use of Regional Stream Condition Inventory (SCI) protocol to assess and document aquatic conditions. Additionally, SCI meets Forest requirements under the Clean Water Act to monitor the effectiveness of the Best Management Practices (BMPs) within a watershed to evaluate the effectiveness of project BMPs in protecting downstream water quality protection and meets in-channel monitoring requirements under the Region 5 Best Management Practices Effectiveness Evaluation Program (BMPEP). SCI attributes and protocols are designed to measure a suite of characteristics of inventorying stream conditions at a specific time and place. SCI consists of established and proven stream assessment techniques that are organized into a package that can be measured in the field in a complimentary and time-effective manner. Each attribute has a protocol for field measurement and these protocols are the keystones to the success of the SCI since accurate data collection over time is essential. SCI is designed so reliable and repeatable measurements can be made to detect change. SCI is primarily designed for use on perennial streams with gradients up to about 10 percent that can be successfully waded. The Sequoia National Forest uses SCI to document stream characteristics and determine a range of natural variability for the watersheds. A summary of all the SCI sites within the Giant Sequoia National Monument can be found in Appendix D. Evaluation of existing stream stability surveys and riparian ecotypes, within giant sequoia groves, have yielded a need to develop a rating system. Inventory priority ratings were developed to determine areas requiring surveys prior to project planning and/or implementation to ensure ecological processes, composition, and structure are adequately considered in land management planning. Further information can be found in Appendix E. Aquatic insects are considered Management Indicator Species (MIS) at the regional level and are a good indicator of Aquatic Habitat condition. Aquatic insects are collected as part of SCI monitoring. Insects are sent to the “Bug Lab” at University of Utah, Logan for identification and classification. Aquatic insect reports include numerous parameters which are available upon request. The forest has provided one of the indices used to describe the sample. The index provided in this report is the Hilsenhoff Biotic Index that divides organisms into groups based on the amount of organic pollution present (Zimmerman 1993). The Hilsenhoff Biotic Index has been used to detect nutrient enrichment, high sediment loads, low dissolved oxygen, and thermal impacts. The index is best at detecting organic pollution. Values are defined in Table 1 as follows: Table 1- Hilsenhoff Biotic Index Water Quality Degree of Organic Pollution 0.00–3.50 Excellent No apparent organic pollution 3.51–4.50 Very good Possible slight organic pollution 4.51–5.50 Good Some organic pollution 5.51–6.50 Fair Fairly significant organic pollution Hydrology Report GSNM Specialist Report 3 Hydrology Report Table 1- Hilsenhoff Biotic Index Water Quality Degree of Organic Pollution 6.51–7.50 Fairly poor Significant organic pollution 7.51–8.50 Poor Very significant organic pollution 8.51–10.0 Very poor Severe organic pollution Figure 1 provides a general view of water quality for Monument lands as indicated by aquatic insects. The majority of monument waters are indicative of excellent water quality with no apparent organic pollution. Comparison of the Monument lands in the north, Hume Lake area, Figure 2, versus Monument lands to the south, Western Divide area, Figure 3, indicates a slight increase in organic pollution to the south as a result of sampling in four streams where biotic indices suggest water quality of a fair rating. Individual watershed details are discussed further and in more detail at the HUC 6 and 7 watershed levels. GSNM Specialist Report Hydrology Report 4 Hydrology Report Hydrology Report GSNM Specialist Report 5 Hydrology Report Characterization of Monument Watersheds Waters from Monument lands flow into the Tulare lakebed. The Tulare lakebed is located in the southern San