Comprehensive Recreational Use-Attainability Analysis Of the Arroyo Colorado Above Tidal Segment 2202 Report to TMDL Program Texas Commission on Environmental Quality Project Work Order Number 582-11-11308-1 Nueces River Authority September 16, 2011 Arroyo Colorado Above Tidal RUAA Report Table of Contents ...................................................................................................................................... 2 List of Acronyms ...................................................................................................................................... 4 Introduction ............................................................................................................................................... 5 Problem Statement ........................................................................................................................ 6 Objectives ..................................................................................................................................... 6 Study Area ................................................................................................................................................ 6 Description of Water Body and Designated Uses and Criteria..................................................... 6 Environmental Features and Population Characteristics .............................................................. 7 Watershed Characterization ........................................................................................................ 10 Public Recreation Areas .............................................................................................................. 10 Permitted Discharges (Municipal, Industrial, Stormwater) ........................................................ 13 Potential Nonpoint Sources......................................................................................................... 15 Summary of Historical Information ............................................................................................ 16 Site Reconnaissance Summary ................................................................................................... 17 Methodologies......................................................................................................................................... 18 RUAA Survey and Site Descriptions .......................................................................................... 18 Sampling Methods ...................................................................................................................... 32 Survey Descriptions .................................................................................................................... 33 Results and Discussions .......................................................................................................................... 34 Physical Evaluation and Flow ..................................................................................................... 34 Recreational Uses........................................................................................................................ 37 Interviews .................................................................................................................................... 47 Summary ................................................................................................................................................. 48 Literature Cited ....................................................................................................................................... 49 RUAA Summary Form ........................................................................................................................... 50 Tables: Table 1 2000 and 2010 Recreational Use Standards ............................................................................... 5 Table 2 IBWC Flow Data ...................................................................................................................... 33 Table 3 Stream miles and surveys Completed ....................................................................................... 34 Table 4 Riparian Zone Category Classifications for Left and Right Banks ........................................... 36 Table 5 Hydrologic Stream Characteristics ............................................................................................ 37 Table 6 RUAA Summary for Each Site .................................................................................................. 39 Table 7 Recreation Observed During Field Surveys at Each Site .......................................................... 42 Table 8 Indications of Human Use Recorded During Surveys at Each Site ........................................... 43 Table 9 Conditions Observed During Field Surveys at Each Site That Promote Recreation ................. 44 Table 10 Conditions Observed During Field Surveys at Each Site That Impede Recreation ................ 46 Table 11 Chanel Obstruction Observed During Field Surveys at Each Site .......................................... 47 Figures: Figure 1 Watershed Map ........................................................................................................................... 7 Figure 2 Hydrography Map ...................................................................................................................... 8 Figure 3 Urban Areas, Cities & Colonias ................................................................................................. 9 Figure 4 Land Use Map ......................................................................................................................... 10 Figure 5 Recreation Areas ..................................................................................................................... 11 Figure 6 Recreation Areas ..................................................................................................................... 11 - 2 - Arroyo Colorado Above Tidal RUAA Report Figure 7 Recreation Areas ..................................................................................................................... 12 Figure 8 Recreation Areas ..................................................................................................................... 12 Figure 9 Permitted Discharges ................................................................................................................ 13 Figure 10 Permitted Discharges .............................................................................................................. 14 Figure 11 Permitted Discharges .............................................................................................................. 14 Figure 12 Permitted Discharges .............................................................................................................. 15 Figure 13 Map of Assessment Unit_01 Station Locations .................................................................... 20 Figure 14 Map of Assessment Unit_02 Station Locations .................................................................... 23 Figure 15 Map of Assessment Unit_03 Station Locations .................................................................... 27 Figure 16 Map of Assessment Unit_04 Station Locations .................................................................... 32 Figure 17 Photo of Observed Primary Contact Recreation at Station 13074 AU_01 ........................... 40 Figure 18 Photo of Observed Primary Contact Recreation at Station 13084 AU_04 ........................... 40 Figure 19 Photo of Observed Secondary Contact Recreation at Station 16444 AU_03 ....................... 41 Appendix A Site IDs and Locations ....................................................................................................... 51 Appendix B Permitted Outfalls ............................................................................................................... 53 - 3 - Arroyo Colorado Above Tidal RUAA Report LIST OF ACRONYMS ACBIS Arroyo Colorado Bacteria Indicator Study ACWP Arroyo Colorado Watershed Partnership ADCP Acoustic Doppler Current Profiler AU Assessment Unit BMP Best Management Practice CFS Cubic Feet per Second BMP Best Management Practice CFS Cubic Feet per Second CWA Clean Water Act IBWC International Boundary and Water Commission NIST National Institute of Standards and Technology NRA Nueces River Authority OBS Observed REP Represented RUAA Recreational Use Attainability Analysis SWQM Surface Water Quality Monitoring TCEQ Texas Commission on Environmental Quality TPWD Texas Parks and Wildlife Department TSSWCB Texas State Soil and Water Conservation Board TSWQS Texas Surface Water Quality Standards TWRI Texas Water Resources Institute USGS United States Geological Survey WWP Watershed Protection Plan WWTF Wastewater Treatment Facility - 4 - Arroyo Colorado Above Tidal RUAA Report Introduction Under the federal Clean Water Act (CWA) the state of Texas is required to assess all water bodies to ensure they are meeting their designated uses. The state of Texas water quality standards are based on criteria related to the designated uses of specified water bodies. A water body is considered impaired if it does not meet the criteria for support of one or more of its designated uses. Some of the designated uses in the state of Texas include aquatic life use, contact recreation, public water supply, fish consumption,