Draft Habitat Conservation Plan for Managed Groundwater Withdrawals from the Barton Springs Segment of the Edwards Aquifer Applicant: Barton Springs/Edwards Aquifer Conservation District Prepared by: Barton Springs/Edwards Aquifer Conservation District For: U.S. Fish & Wildlife Service Austin, Texas Initially Submitted - November 20, 2014 Last revised – May 25, 2017 ii Prepared By: District Staff: John T Dupnik, P.G., General Manager Brian A Smith, Ph.D. P.G., Principal Hydrogeologist Brian B Hunt, P.G., Senior Hydrogeologist Justin Camp, Hydrogeologic Technician Robin H Gary, Senior Public Information Coordinator and GIS Specialist Kendall Bell-Enders, Regulatory Compliance Coordinator Vanessa Escobar, Regulatory Compliance Coordinator Dana C Wilson, Senior Administrative Specialist and Editor Consultants: W F (Kirk) Holland, P.G., Management Consultant (and Former GM) Mary Poteet, Ph.D., University of Texas, Integrative Biology Art Woods, Ph.D., (Formerly) University of Texas, Integrative Biology Bryan Brooks, Ph.D., Consultant in Biology and Ecology Kent S Butler, Ph.D. (Deceased), Project Management Consultant and Advisor Under Direction of the District’s 2016-2018 Board of Directors: Mary Stone, Director Precinct 1 Blayne Stansberry, President, and Director Precinct 2 Blake Dorsett, Secretary, and Director Precinct 3 Robert D Larsen, Ph.D., Director Precinct 4 Craig Smith, Vice President, and Director Precinct 5 iii iv Draft Habitat Conservation Plan for Managed Groundwater Withdrawals from the Barton Springs Segment of the Edwards Aquifer Table of Contents Table of Contents ....................................................................................................................................... v List of Figures ............................................................................................................................................ x List of Tables ............................................................................................................................................. xi List of Acronyms, Abbreviations, and Terms Used in This Document .............................................. xii Acknowledgments ................................................................................................................................... xiv Executive Summary .................................................................................................................................. 1 1.0 Introduction and Background ........................................................................................ 5 2.0 Purpose and Need for HCP/ITP ..................................................................................... 7 2.1 Purpose .............................................................................................................................. 7 2.2 Need .................................................................................................................................. 7 2.2.1 Programmatic Basis of Need ............................................................................................. 7 2.2.2 Statutory Basis of Need: Endangered Species Act ............................................................ 9 2.3 Correspondence between HCP Sections and Information Required by Service ............. 10 2.3.1 Information Requirements of an HCP in Support of an ITP ........................................... 11 2.3.2 Findings for Service to Issue an ITP ............................................................................... 11 2.3.3 Additional Guidance and Recommendations for Developing HCPs (“Five Point Policy”) ......................................................................................................................................... 11 3.0 Description of Areas Analyzed ..................................................................................... 13 3.1 Planning Area .................................................................................................................. 13 3.1.1 General Environmental Setting of Planning Area ........................................................... 13 3.1.1.1 Physical Environment ...................................................................................................... 13 3.1.1.2 Biological Environment................................................................................................... 15 3.1.1.3 Man-made Environment .................................................................................................. 17 3.1.2 Hydrogeologic Framework of Planning Area ................................................................. 18 3.1.2.1 Aquifers and Hydrozones ................................................................................................ 19 3.1.2.2 Groundwater Flow Conditions ........................................................................................ 21 3.1.3 Barton Springs/Edwards Aquifer Conservation District Jurisdictional Area .................. 24 3.2 Incidental Take Permit Area ............................................................................................ 25 v 3.2.1 Subsurface Part of District’s Exclusive Territory ........................................................... 25 3.2.2 Spring Outlets Area ......................................................................................................... 27 3.2.2.1 Physical Setting ............................................................................................................... 27 3.2.2.1.1 Physical Characteristics of Barton Springs .............................................................. 27 3.2.2.1.2 Sources and Implications of Variation in Springflow at Barton Springs ................. 27 3.2.2.2 Ecological Setting ............................................................................................................ 35 3.2.2.2.1 Overview of Habitat Characteristics and Supported Populations ............................ 35 3.2.2.2.2 Water Chemistry and Springflow Relationships ...................................................... 39 3.2.3 Antecedent Conditions in ITP Area ................................................................................ 45 3.2.4 Protected Species in ITP Area ......................................................................................... 47 4.0 Proposed Actions ........................................................................................................... 49 4.1 Proposed Covered Activities ........................................................................................... 49 4.1.1 Regulated Groundwater Community ............................................................................... 49 4.1.1.1 Exempt Wells and Users ................................................................................................. 51 4.1.1.2 Nonexempt Wells and Users ........................................................................................... 53 4.1.1.2.1 Nonexempt Domestic-Use Wells and Users ............................................................ 54 4.1.1.2.2 Other Nonexempt Wells and Users .......................................................................... 55 4.1.2 Historical Perspective of Covered Activities .................................................................. 56 4.1.2.1 Evolution of Regulatory Program ................................................................................... 56 4.1.2.2 Changes to Pre-HCP Baseline ......................................................................................... 61 4.1.3 Statutory and Regulatory Authorities for Covered Activities and Integrated Conservation Measures .......................................................................................................................... 65 4.1.4 Public Participation in Developing Covered Activities and Integral Conservation Measures .......................................................................................................................... 68 4.2 Requested Permit Duration ............................................................................................. 69 5.0 Analysis of Impacts Likely to Result from Taking ..................................................... 71 5.1 Covered Species .............................................................................................................. 71 5.1.1 Species Descriptions and Life Histories .......................................................................... 71 5.1.1.1 Barton Springs Salamander ............................................................................................. 71 5.1.1.2 Austin Blind Salamander ................................................................................................. 75 5.1.2 Species Distribution ........................................................................................................ 75 5.1.2.1 Barton Springs Salamander ............................................................................................. 75 5.1.2.2 Austin Blind Salamander ................................................................................................. 76 5.1.3 Reasons for Decline and Threats to Survival .................................................................. 78 5.1.3.1 Barton Springs Salamander ............................................................................................. 79 5.1.3.2 Austin Blind Salamander ................................................................................................