Reserve Determination Studies for Selected Surface Water, Groundwater, Estuaries and Wetlands in the Usutu/Mhlatuze Water Management Area Wp 10544
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! RESERVE DETERMINATION STUDIES FOR SELECTED SURFACE WATER, GROUNDWATER, ESTUARIES AND WETLANDS IN THE USUTU/MHLATUZE WATER MANAGEMENT AREA WP 10544 GROUNDWATER-WETLAND INTEGRATION REPORT: VOLUME 1 – WETLAND PRIORITISATION DRAFT REPORT DECEMBER 2014 Report No. RDM/WMA6/CON/COMP/1013 DEPARTMENT OF WATER & SANITATION DIRECTORATE: RESOURCE DIRECTED MEASURES CONTRACT NO. WP 10544 RESERVE DETERMINATION STUDIES FOR SELECTED SURFACE WATER, GROUNDWATER, ESTUARIES AND WETLANDS IN THE USUTU/MHLATUZE WATER MANAGEMENT AREA: INTEGRATED GROUNDWATER WETLAND WATER RESOURCE UNITS VOLUME 1: WETLAND PRIORITISATION DRAFT VERSION 1.4 DECEMBER 2014 RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} Copyright reserved: No part of this publication may be reproduced in any manner without full acknowledgement of the source. WETLAND PRIORITISATION Page i RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} This report should be cited as: Department of Water Affairs (DWA). 2014. Resource Directed Measures: Reserve determination study of selected surface water and groundwater resources in the Usutu/Mhlathuze Water Management Area. Integrated Groundwater-Wetland Water Resource Units. Volume 1: Wetland Prioritisation. Report produced by Wetland Consulting Services (Pty) Ltd for Tlou Consulting (Pty) Ltd for the Department of Water and Sanitation. Report no: RDM/WMA6/CON/COMP/1013. WETLAND PRIORITISATION Page ii RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} Contract Title: Reserve determination studies for selected surface water, groundwater, estuaries and wetlands in the Usutu - Mhlathuze Water Management Area Report Title: Intergrated Groundwater Wetland Water Resource Units. Volume 1: Wetland Prioritisation Authors: Bhuti Dlamini – Wetland Consulting Services (Pty) Ltd. Gary Marneweck - Wetland Consulting Services (Pty) Ltd. Editor: Adhishri Singh – Tlou Consulting (Pty) Ltd. Revision Date Report Status Draft 1.2 4 September 2014 Draft to Client Draft 1.3 17 October 2014 Revised draft to Client Draft 1.4 8 December Resubmission as per request from Client Prepared for the Consultants by: Checked for the Consultants by: ………………………………………….. ……………………………………….. Bhuti Dlamini Cate Brown Wetland Specialist Internal Reviewer Client: Department of Water & Sanitation Approved for the DWS: ………………………………………….. N Mohapi Chief Director: Resource Directed Measures INTEGRATED GROUNDWATER-WETLAND WATER RESOURCE UNITS: VOLUME 1 - WETLAND PRIORITISATION Page iii RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} ACKNOWLEDGEMENTS This report was compiled by Mr. Bhuti Dlamini and Gary Marneweck of Wetland Consulting Services (Pty) Ltd. with specialist input from the following project members. Contributors: Miss S. Davis – Wetland Ecologist at Wetland Consulting Services (Pty) Ltd. Mr. H Ortmann – Was a junior specialist at Wetland Consulting Services (Pty) Ltd during the field surveys. Mr. S. Driskill - GIS Specialist at Wetland Consulting Services (Pty) Ltd. INTEGRATED GROUNDWATER-WETLAND WATER RESOURCE UNITS: VOLUME 1 - WETLAND PRIORITISATION Page iv RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} TABLE OF CONTENTS 1 BACKGROUND INFORMATION ................................................................................................ 1 2 LIMITATIONS & ASSUMPTIONS ............................................................................................... 2 3 DESCRIPTION OF THE STUDY AREA ......................................................................................... 3 3.1 REVIEW OF LITERATURE PERTAINING TO WETLANDS IN THE STUDY AREA .................................................. 5 3.1.1 Wetland definition .............................................................................................................. 5 3.1.2 Wetland ecoregions in the study area ................................................................................ 5 3.1.3 Summary of existing information ........................................................................................ 7 3.1.4 Values of wetlands within the WMA (DWA, 2010) ........................................................... 10 4 APPROACH AND METHODOLOGY ......................................................................................... 13 4.1 DELINEATION OF RESOURCE UNITS WITHIN THE WMA (PARSONS, 2009 & DENNIS AND DENNIS, 2009) .. 13 4.2 WETLAND TYPING AND ECOLOGICAL CLASSIFICATION .......................................................................... 15 4.2.1 Wetland typing .................................................................................................................. 15 4.2.2 Wetland Mapping ............................................................................................................. 19 4.2.3 Categorisation ................................................................................................................... 19 4.3 THREATENED ECOSYSTEM TYPES OCCURRING IN THE USUTHU-MHLATUZE WMA .................................... 22 4.4 WETLAND VEGETATION TYPES OCCURRING IN THE USUTU-MHLATUZE WMA: ....................................... 24 4.5 WETLAND PRIORITISATION ............................................................................................................. 26 5 FINDINGS ............................................................................................................................. 28 5.1 CATCHMENT ASSESSMENT ............................................................................................................. 28 5.1.1 Usutu Catchment ............................................................................................................... 28 5.1.2 Pongola Catchment ........................................................................................................... 31 5.1.3 Mkuze Catchment ............................................................................................................. 34 5.1.4 Mfolozi Catchment ............................................................................................................ 38 5.1.5 Lake Sibaya and Kosi Bay Catchments .............................................................................. 41 5.1.6 Mhlatuze Catchment ......................................................................................................... 43 5.2 IMPACTS AND THREAT ANALYSIS ..................................................................................................... 47 5.2.1 Broader Impacts on wetlands within the WMA ................................................................ 47 5.2.2 Broader Threats on wetlands within the WMA ................................................................. 51 5.3 PRIORITY WETLAND AREAS ............................................................................................................. 51 5.3.1 Priority Wetlands 1 – High Priority wetlands outside protected areas (Vulnerable systems) ......................................................................................................................................... 51 5.3.2 Priority Wetlands 2 – High Priority wetlands within protected areas ............................... 54 5.3.3 Priority Wetlands 3 – High Priority wetlands based on Beggs (1989), prioritisation work and Wetland Freshwater Ecosystem Priority Areas (FEPAs). ........................................................ 56 5.3.4 Priority Wetlands 4 – Wetlands that are likely to be groundwater driven ....................... 58 6. DEVELOPMENT OF PRELIMINARY MANAGEMENT AND MONITORING REQUIREMENTS FOR THE WETLANDS ................................................................................................................................. 63 7. REFERENCES ........................................................................................................................ 66 8. APPENDIX 1 – RED DATA BIRDS SPECIES ............................................................................... 69 9. APPENDIX 2 (HGM DIAGRAMS – TAKEN FROM OLLIS ET AL., 2013 ........................................ 70 11. APPENDIX 3 – WETLAND CATEGORISATION & TYPING - TABLES ............................................. 75 INTEGRATED GROUNDWATER-WETLAND WATER RESOURCE UNITS: VOLUME 1 - WETLAND PRIORITISATION Page v RESERVE DETERMINATION STUDY FOR THE USUTU – MHLATUZE CATCHMENTS REPORT NO. {RDM/WMA6/CON/COMP/1013} TABLE OF FIGURES FIGURE 3-1: MAP SHOWING LOCATION AND EXTENT OF THE WMA INCLUDING SURROUNDING TOWNS. ............ 4 FIGURE 3-2: WETLAND REGION OF SOUTH AFRICA (COWAN, 1995 PP. 25)................................................... 6 FIGURE 4-1: MAP SHOWING THE RESOURCE UNITS OF THE USUTU TO MHLATUZE WATER MANAGEMENT AREA (DENNIS AND DENNIS, 2009). ........................................................................................................... 14 FIGURE 4-2-1: MAP OF THE WETLANDS IN THE UPPER SECTION OF THE USUTU-MHLATUZE WMA. .............. 17 FIGURE 4-6: MAP SHOWING THE THREATENED ECOSYSTEM TYPES OCCURRING WITHIN THE USUTU TO MHLATUZE WATER MANAGEMENT AREA. .......................................................................................... 25 FIGURE 5-1: RU LOCATION AND EXTENT WITHIN THE USUTU CATCHMENT. ................................................. 30 FIGURE 5-2: RU LOCATION AND EXTENT WITHIN THE PONGOLA CATCHMENT. ............................................