7 Adara Street Midstream Ridge 082 921 5445 [email protected] Aquatic fauna assessment for the upgrade of the Bushkoppies Waste Water Treatment Works July 2019 Compiled by: Mr Bertus Fourie (M.Sc. Aquatic Health, Pr. Sci. Nat) 1 of 54 pages TABLE OF CONTENTS 1. INTRODUCTION............................................................................................................................. 6 1.1. BACKGROUND ................................................................................................................................................ 6 1.2. SCOPE OF WORK ............................................................................................................................................. 7 2. ASSUMPTIONS AND LIMITATIONS .................................................................................................. 7 3. SITE LOCATION AND DESCRIPTION ................................................................................................. 8 3.1. ACTIVITIES ON SITE .......................................................................................................................................... 8 3.2. REGIONAL DESCRIPTION AND VEGETATION.......................................................................................................... 8 3.2.1. Gm 9 Tsakane Clay Grassland ......................................................................................................... 8 3.3. ECOREGION DESCRIPTION............................................................................................................................... 10 3.4. CATCHMENT DESCRIPTION ............................................................................................................................. 11 4. METHODS ....................................................................................................................................12 4.1. FISH POPULATION RESPONSE ASSESSMENT........................................................................................................ 12 4.1.1. Step 1: Selection of river for assessment ...................................................................................... 13 4.1.2. Step 2: Determination of the reference fish assemblage ............................................................ 13 4.1.3. Reference FROC list (0 = absent and 5 = very abundant)............................................................. 13 4.1.4. Step 3: Determination of the present state of drivers ................................................................. 14 4.1.5. Step 4: Selection of representative sampling sites ....................................................................... 14 4.1.6. Step 5: Determination of fish habitat condition ........................................................................... 14 4.1.7. Step 6: Fish sampling...................................................................................................................... 15 4.1.8. Step 7: Collate and analyse fish sampling data............................................................................ 15 4.1.9. Step 8: Execution of FRAI model .................................................................................................... 15 4.2. SASS 5 METHOD .......................................................................................................................................... 16 4.2.1. Invertebrate Habitat Assessment System (IHAS) ......................................................................... 18 4.3. WATER SAMPLING PROCEDURE: IN SITU WATER QUALITY.................................................................................... 19 4.4. WATER SAMPLING PROCEDURE: LABORATORY SAMPLING (FIGURE 5) .................................................................. 19 4.4.1. Physical properties of water .......................................................................................................... 20 4.4.2. Chemical properties of water ........................................................................................................ 21 5. RESULTS ......................................................................................................................................30 5.1. IMPACTS ...................................................................................................................................................... 32 5.2.1. In situ ............................................................................................................................................... 32 5.2.2. Laboratory assessment .................................................................................................................. 33 6.1. MITIGATION OF PROPOSED IMPACT ................................................................................................................. 47 2 of 54 pages 6.1.1. Site specific mitigation measures .................................................................................................. 47 7. CONCLUSION AND RECOMMENDATIONS .......................................................................................48 8. REFERENCES ................................................................................................................................48 9. APPENDIX A: GLOSSARY OF TERMS: ..............................................................................................50 10. APPENDIX B: ACRONYMS ..........................................................................................................52 FIGURES: FIGURE 1: STUDY SITE LOCATION ....................................................................................................... 8 FIGURE 2: THE CATCHMENT AND HYDROLOGICAL DATA FOR THE STUDY SITE, AS AVAILABLE FROM DWA RQS SERVICES. .................................................................................................... 11 FIGURE 3: LIST OF FROC SITES NEAR THE STUDY SITE AS PART OF QUATERNARY CATCHMENT ...... 13 FIGURE 4: IMAGE OF THE FRABIL MINNOW TRAPS ............................................................................ 15 FIGURE 5: WATER SAMPLING PROCEDURE ........................................................................................ 19 FIGURE 6: AQUATIC BIOMONITORING SAMPLE SITE LOCATION. .................................................. 30 FIGURE 7: UPPER SAMPLE SITE- NOTE DARK COLOUR OF THE WATER WITH FLOCCULANTS ASSUMED TO BE TOILET PAPER ................................................................................................................... 31 FIGURE 8: OUTLET FROM THE OXIDATION PONDS INTO THE MAIN CHANNEL .................................... 31 FIGURE 9: MIXING OF WATER FROM THE OXIDATION PONDS INTO THE MAIN CHANNEL ................... 32 FIGURE 10: WATER QUALITY SAMPLE POINTS .................................................................................. 33 FIGURE 11: WATER QUALITY ANALYSIS RESULTS............................................................................. 34 FIGURE 12: UPPER SAMPLE POINT .................................................................................................. 37 FIGURE 13: NORTH SAMPLE POINT................................................................................................. 38 FIGURE 14: BIOMONITORING A SASS RESULTS ............................................................................ 39 FIGURE 15: BIOMONITORING B SASS RESULTS ............................................................................ 40 TABLES: TABLE 1: THE EIGHT STEPS OF FRAI AS DESCRIBED BY KLEYNHANS, 2007 ..................................... 12 TABLE 2: FROC SPECIES LIST FOR THE STUDY SITE (*INDICATES ALIEN EXOTIC SPECIES) ............... 14 TABLE 3: THE PRESENT ECOLOGICAL STATE CATEGORY INTERPRETATION GUIDE ........................... 16 TABLE 4: ECOLOGICAL CATEGORIES FOR INTERPRETING SASS DATA ............................................. 18 TABLE 5: TABLE FOR COMPARATIVE RESULTS OF PHYSICAL PROPERTIES OF WATER................ 20 TABLE 6: SOME OF THE CHEMICAL ASPECTS TESTED FOR ............................................................ 22 TABLE 7: FAECAL COLIFORM RESULT INTERPRETATION GUIDE .................................................. 29 TABLE 8: WATER QUALITY PARAMETERS ASSESSMENT................................................................ 33 3 of 54 pages TABLE 9: WATER QUALITY ANALYSIS RESULTS WITH WATER QUALITY TARGET ............................. 35 TABLE 10: SASS RESULTS SUMMARY ............................................................................................. 38 TABLE 11: IHAS RESULTS FOR BIOMONITORING A SITE .............................................................. 41 TABLE 12: IHAS OF BIOMONITORING B ........................................................................................ 42 TABLE 13: MIRAI CALCULATION RESULTS. .................................................................................. 43 TABLE 14: FRAI ASSESSMENT RESULTS......................................................................................... 44 4 of 54 pages DECLARATION OF INDEPENDENCE I, Bertus Fourie, declare that - I am subcontracted as specialist consultant by Limnology for the project. I will perform the work relating to the application in an objective manner, even if this results in views and findings that are not favourable to the applicant; I declare that there are no circumstances that may compromise my objectivity in performing such work; I have expertise in conducting the specialist report