State of Environment Outlook Report for the Western Cape Province. Inland
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State of Environment Outlook Report for the Western Cape Province Inland Water February 2018 i State of Environment Outlook Report for the Western Cape Province CUMENT DESCRIPTION Document Title and Version: Final Inland Water Chapter Client: Western Cape Department of Environmental Affairs & Development Planning Project Name: State of Environment Outlook Report for the Western Cape Province 2014 - 2017 SRK Reference Number: 507350 SRK Authors: Xanthe Adams, Sharon Jones, Daniell Du Preez SRK GIS Team : Masi Fubesi and Keagan Allan SRK Review: Christopher Dalgliesh, Sharon Jones & Jessica du Toit DEA&DP Project Team: Karen Shippey, Ronald Mukanya and Francini van Staden Acknowledgements: Western Cape Government Environmental Affairs & Development Planning: Catherine Bill, Marlé Kunneke, Sarah Birch, Frances van der Merwe, Lize Jennings-Boom Department of Water and Sanitation Melissa Lintnaar-Strauss, Andrew Gordon City of Cape Town Candice Haskins Other David L’ Maitre (CSIR), Kate Snaddon (Freshwater Consulting Group), Edward Molteno (Kogelberg Nature Reserve) Photo Credits: Page 1 – Bruce Sutherland Page 3 – Cecile Liebenberg Page 4 – Photo source unknown Page 5 – Sue Reuther Page 22 – Johan Roux Page 27 – EWN Date: February 2018 State of Environment Outlook Report for the Western Cape Province i TABLE OF CONTENTS 1 INTRODUCTION __________________________________________________________________________ 1 2 DRIVERS AND PRESSURES __________________________________________________________________ 1 2.1 Climate change _____________________________________________________________________ 2 2.2 Human settlements __________________________________________________________________ 2 2.2.1 Informal settlements _______________________________________________________________ 2 2.2.2 Formal urban settlements __________________________________________________________ 2 2.3 Agriculture and industry ______________________________________________________________ 3 2.3.1 Agriculture ________________________________________________________________________ 3 2.3.2 Forestry ___________________________________________________________________________ 4 2.3.3 Aquaculture ______________________________________________________________________ 4 2.3.4 Other industries ____________________________________________________________________ 5 2.4 Invasive alien plants _________________________________________________________________ 5 3 STATE ____________________________________________________________________________________ 6 3.1 Water availability ____________________________________________________________________ 8 3.1.1 Drought conditions in the Western Cape ____________________________________________ 8 3.1.2 Long term water balances ________________________________________________________ 10 3.1.3 Water supply and consumption ___________________________________________________ 13 3.1.4 Groundwater supply ______________________________________________________________ 15 3.1.5 Invasive alien vegetation _________________________________________________________ 16 3.1.6 Other water sources ______________________________________________________________ 16 3.2 Fitness for use_______________________________________________________________________ 18 3.2.1 Eutrophication and salinisation ____________________________________________________ 19 3.2.2 Microbial contamination __________________________________________________________ 20 3.2.3 Emerging contaminants __________________________________________________________ 22 3.2.4 Groundwater quality _____________________________________________________________ 22 3.3 Inland water ecosystem health ______________________________________________________ 22 3.3.1 Rivers ____________________________________________________________________________ 23 3.3.2 Wetlands ________________________________________________________________________ 24 4 IMPACTS _______________________________________________________________________________ 27 4.1 Impacts of inadequate water availability ____________________________________________ 27 4.2 Impacts of poor water quality _______________________________________________________ 28 4.3 Inland water ecosystem health ______________________________________________________ 28 5 RESPONSES _____________________________________________________________________________ 29 5.1.1 Legislation, policy and governance structures ______________________________________ 29 5.1.2 Water resource reserve determination _____________________________________________ 29 5.2 Strategies and reconciliation plans for water availability ______________________________ 29 5.2.1 Planning _________________________________________________________________________ 29 5.2.2 Sustainable Water Management __________________________________________________ 31 5.2.3 Implementation __________________________________________________________________ 32 5.3 Green Drop Programme ____________________________________________________________ 33 5.4 Alien invasive clearing ______________________________________________________________ 33 5.5 Inland water ecosystem health and water quality initiatives ___________________________ 33 5.5.1 Working for Wetlands _____________________________________________________________ 33 5.5.2 Other river and wetland rehabilitation initiatives ____________________________________ 34 5.6 Research and data management ___________________________________________________ 34 ii State of Environ ment Out look Repo rt for the Weste rn Cape Pro vince 5.7 Mitigation and adaptation __________________________________________________________ 35 6 CONCLUSION ___________________________________________________________________________ 35 7 REFERENCES ____________________________________________________________________________ 38 TABLE OF FIGURES Figure 3-1: Core principles of sustainable water use __________________________________________ 6 Figure 3-2: Water bodies and Water Management Areas of the Western Cape ________________ 7 Figure 3-3: Selected developments during the drought _______________________________________ 9 Figure 3-4: Seasonal rainfall records for South Africa between July 2012 and April 2017 _________ 10 Figure 3-5: Water availability for towns in the Western Cape _________________________________ 12 Figure 3-6: Water use in the WCWSS in 2006 and 2015________________________________________ 13 Figure 3-7: Water supply and water uses in the Berg-Olifants WMA ____________________________ 14 Figure 3-8: Water supply and water uses in the Breede-Gouritz WMA _________________________ 15 Figure 3-9: Percentage reduction in mean annual runoff due to alien vegetation _____________ 17 Figure 3-10: Water quality (salinisation and eutrophication) for each catchment _______________ 20 Figure 3-11: Presence of e-coli expressed as risk in the Western Cape _________________________ 21 Figure 3-12: Percentage of river length within each PES category _____________________________ 24 Figure 3-13: Present Ecological State (PES) for rivers in the Western Cape ______________________ 25 Figure 3-14: Wetland condition map for the Western Cape ___________________________________ 26 Figure 5-1: High growth scenario, 50% successful WC/WDM, no climate change and based on a one in 50 year assurance of supply. ______________________________________________ 30 Figure 5-2: High growth scenario, 50% successful WC/WDM, climate change and based on a one in 50 year assurance of supply. __________________________________________________ 31 Figure 5-3: Strategic objectives of the SWMP ________________________________________________ 32 LIST OF TABLES Table 3-1: Water management areas and major rivers of the Western Cape __________________ 6 Table 3-2: Water resource supply and consumption_________________________________________ 11 Table 3-3: Updated water demand for selected WMAs _____________________________________ 11 Table 3-4: Utilisable Groundwater Exploitation Potential (UGEP) for each WMA _______________ 16 Table 3-5: Major water quality concerns in the Western Cape _______________________________ 19 Table 3-6: Summarised major disturbances to inland water ecosystems ______________________ 23 Table 3-7: Present Ecological State (PES) categories and descriptions ________________________ 23 Table 3-8: Wetland conditions classifications _______________________________________________ 27 Table 5-1: Possible intervention programme for the WCWSS Planning Scenario ________________ 30 Table 6-1: Summary of the outlook for inland water in the Western Cape _____________________ 36 Table 6-2: Overview of key inland water aspects ___________________________________________ 37 ANNEXURES Annexure A Summary of key policy, tools and legislation Annexure B Declaration of Intent ABBREVIATIONS AND ACRONYMS CMA Catchment Management Agency CCT City of Cape Town CRR Cumulative Risk Rating State of Environment Outlook Report for the Western Cape Province iii DAFF Department of Agriculture, Forestry and Fisheries DEA Department of Environmental Affairs DEA&DP Department of Environmental Affairs and Development Planning DWA Department of Water Affairs (see DWS) DWAF Department of Water Affairs and Forestry (see DWS) DWS Department of Water and Sanitation (previously DWAF and DWA) E. coli Escherichia coli Bacteria EPWP Expanded Public Works Programme NEMA National Environmental Management Act 107 of 1998 NFEPA National Freshwater Ecosystem Priority Areas NWA National Water Act 36 of 1998 PES Present Ecological State RQIS Resource Quality Information