LONG TERM ADAPTATION SCENARIOS - TOGETHER DEVELOPING ADAPTATION RESPONSES FOR FUTURE CLIMATES
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LONG TERM ADAPTATION SCENARIOS
TOGETHER DEVELOPING ADAPTATION RESPONSES FOR FUTURE CLIMATES
WATER
environmental affairs
Department:
Environmental Affairs
REPUBLIC OF SOUTH AFRICA
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LONG-TERM ADAPTATION SCENARIOS
FLAGSHIP RESEARCH PROGRAMME (LTAS)
CLIMATE CHANGE IMPLICATIONS
FOR THE WATER SECTOR IN
SOUTH AFRICA
LTAS Phase 1, Technical Report (no. 2 of 6)
The project is part of the International Climate Initiative (ICI), which is supported by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.
environmental affairs
Department:
Environmental Affairs
REPUBLIC OF SOUTH AFRICA
When making reference to this technical report, please cite as follows: DEA (Department of Environmental Affairs). 2013.
Long-Term Adaptation Scenarios Flagship Research Programme (LTAS) for South Africa. Climate Change Implications for the Water Sector
in South Africa. Pretoria, South Africa.
2 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 1
Table of Contents
List of Abbreviations 6 1.6 KwaZulu-Natal Coastal Metropolitan Reconciliation Study 64
Acknowledgements 8 1.7 Luvuvhu and Letaba Reconciliation Study 65
1.8 Mbombela Municipal Area Reconciliation Study 66
The LTAS Phase 1 9
1.9 Mhlathuze Reconciliation Study (Richards Bay) 66
Report Overview 10
1.10 Olifants Reconciliation Study 67
Executive Summary 12
1.11 Orange Reconciliation Study 69
1. Strategic water planning in South Africa 14 1.12 Vaal Reconciliation Study 69
1.1 National planning 15
1.13 Western Cape Reconciliation Study (DWAF, 2007) 71
1.2 Water resource system planning 18
1.3 Water management area/catchment planning 24 Annex 2: Climate change impacts on water resource system yields (case study) 75
1.4 Sub-catchment/municipal planning 26 2.1 System yield-reliability characteristics under climate change 75
2. Climate change impacts on the water sector 27 References 77
2.1 Climate change impacts modelling for the water sector 27
2.2 Climate change impacts on national runoff 28
2.3 Climate change impacts on water quality 29 List of figures
2.4 Climate change impacts on infrastructure 31
2.5 Climate change impacts on water services 31 Figure 1. Water resources planning framework in South Africa. 14
2.6 Climate change impacts on human security 31 Figure 2. Water availability and use. 15
3. Adaptation response options 32 Figure 3. Groundwater exploitation potential. 17
3.1 Integrating adaptation into the water resources planning framework 32
Figure 4 Groundwater use per WMA. 18
3.2 Incorporating climate change adaptation into reconciliation studies 36
Figure 5. Map for removal of invasive alien species. 18
3.3 Adaptation priority measures in the Draft Climate Change Adaptation Strategy for the Water Sector 42
Figure 6. Key economic areas in relation to existing water supply system studies. 20
4. Research requirements 46
Figure 7. Water resource development diagram. 22
5. Conclusion 47
Annex 1: Review of existing reconciliation studies for South Africa 48 Figure 8. Location of the Breede-Overberg WMA. 25
1.1 Stochastic systems analysis methodology 48 Figure 9. Western Cape Water Supply System augmentation options. 26
1.2 Algoa Reconciliation Study 55
Figure 10. Top down versus bottom up approach to planning. 28
1.3 Amatole Reconciliation Study (DWA, 2008a) 57
Figure 11. P
reliminary projected changes in annual runoff for South Africa
1.4 Bloemfontein Reconciliation Study(DWA, 2010b) 60 under unconstrained and constrained emissions scenarios. 29
1.5 Crocodile West Reconciliation Study (DWA, 2008b) 63
2 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 3
Figure 12. P
reliminary projected changes in seasonal runoff for spring, summer, autumn and winter Figure 34. Water demand for the urban areas in the Crocodile West area. 64
for South Africa under unconstrained and constrained emissions scenarios. 29
Figure 35. Mhlatuze water supply area. 66
Figure 13. Median impact of climate change on the average annual catchment runoff for the period
Figure 36. Water availability and requirements for Mhlatuze. 67
2040–2050 under an unconstrained emission scenario. 29
Figure 37. Olifants water supply area. 67
Figure 14. Climate adaptation interventions with reference to the water planning framework. 32
Figure 38. Projected future yield for the Olifants area. 68
Figure 15. Distinction between medium term and long term planning for water, development and climate. 35
Figure 39. Water requirements for high growth scenario. 68
Figure 16. Six hydrological zones developed as part of the National Water Adaptation Strategy process,
reflecting boundaries defined by water management areas (WMAs) in South Africa; Figure 40. Water availability and requirements for the Olifants. 68
and grouped according to their climatic and hydrological characteristics. 37
Figure 41. Vaal water supply area. 70
Figure 17. Key economic areas in relation to existing water supply system studies. 37
Figure 42. Future water requirements for the Vaal. 70
Figure 18. SADC Water Adaptation Cube. 42
Figure 43. Water availability and requirements for the Vaal. 70
Figure 19. An example of a typical Water Resources Yield Model (WRYM) configuration. 52
Figure 44. Map of Western Cape Water Supply System. 70
Figure 20. An example of a typical set of outputs from WRYM. 53
Figure 45. Historical water use. 72
Figure 21. An example of a typical box-whisker diagram output series from a Water Resources Planning Model. 54
Figure 46. Historical and projected water demand for WCWSS. 72
Figure 22. Algoa water supply area. 55
Figure 47. WCWSS reconciliation and supply requirement. 72
Figure 23. Historical water demand for the Algoa area. 56 Figure 48. Preliminary water demand management and water supply options for the WCWSS. 73
Figure 24. Algoa water requirement scenarios. 56 Figure 49. WCWSS augmentation options taking into account a 15% reduction in yield. 74
Figure 25. Water availability and requirements for Algoa. 56 Figure 50. Stochastic yield-reliability characteristics for the five GCM scenarios. 76
Figure 26. Worst case scenario study for the Algoa system. 57 Figure 51. Average changes in MAR for the Berg pilot study. 76
Figure 27. Amatole water supply area. 58
Figure 28. Amatole water availability and requirements. 59
List of tables
Figure 29. Bloemfontein water supply area. 61
Figure 30. Historical urban water use. 62 Table 1. Summary of reconciliation studies to date. 23
Figure 31. Water requirement scenarios for Bloemfontein. 62 Table 2. Primary determinants of usable system yield in a surface water resource context. 49
Figure 32. Water availability and requirements for Bloemfontein. 62 Table 3. Average growth in water demand as a function of population and economic growth models. 73
Figure 33. Crocodile West water supply area. 63 Table 4. Preliminary water demand management and water supply options for the WCWSS. 74
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LIST OF ABBREVIATIONS ABWSS Amatole Bulk Water Supply System NMBM Nelson Mandela Bay Municipality ACRU Agricultural Catchments Research Unit NWRS National Water Resource Strategy ADM Amathole District Municipality NWRS2 National Water Resource Strategy second edition AMD Acid mine drainage ppm Parts per million AWSS Algoa Water Supply System RSS Reconciliation strategy study BOCMA Breede-Overberg catchment management agency SADC Southern African Development Community CMA Catchment management agency SDA Sewage drainage areas CMS Catchment management strategy TCTA Trans-Caledon Tunnel Authority DEA Department of Environmental Affairs UCE Unconstrained emissions DWA Department of Water Affairs URV Unit reference value EC Ecological category WC/WD Water conservation and water demand EWR Environmental water requirement WC/WDM Water conservation and water demand management FWF WWTW Fish Water Flats Wastewater Treatment Works WCCS National Climate Change Strategy for Water Resources GCM Global circulation model WCDM Water conservation and demand management GWS Ground water strategy WCWSS Western Cape Water Supply System HFD Hybrid frequency distribution WGDF Water for Growth and Development Framework IDZ Industrial development zone WMA Water management area IMS Information management system WRC Water Research Commission ISP Internal strategic perspective WRPM Water Resources Planning Model KNP Kruger National Park WRSM2000 Water Resources Simulation (Pitman) Model 2000 L1S level one stabilisation (emissions constrained to 450 ppm CO2e) WRYM Water Resources Yield Model LHWP Lesotho Highlands Water Project WSAM Water Situation Assessment Model m3/km2/a Cubic metres per square kilometre per annum WUA Water users’ association MAR Mean annual runoff WWTW Wastewater treatment works 6 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 7
ACKNOWLEDGEMENTS The LTAS Phase 1
The first phase of the Long Term Adaptation Scenario DEA and SANBI would also like to acknowledge other The Long-Term Adaptation Scenarios (LTAS) Flagship
Flagship Research Programme (LTAS) involved numerous members of the Project Management Team who Research Programme (2012–2014) is a multi-sectoral
people and organisations, and was characterised by a spirit contributed their time and energy to the development of research programme, mandated by the South African
of collaboration and cooperation across organisational and this technical report, namely Mr Shonisani Munzhedziii and National Climate Change Response White Paper
disciplinary boundaries. The Department of Environmental Mr Vhalinavho Khavhagali who provided key guidance on (NCCRP, para 8.8). The LTAS aims to develop national and
Affairs (DEA) and the South African National Biodiversity behalf of the DEA, Prof. Guy Midgley (SANBI), Ms Sarshen sub-national adaptation scenarios for South Africa under
Institute (SANBI) would like to thank the Deutsche Scorgie and Ms Petra de Abreu (Conservation South plausible future climate conditions and development
Gesellschaft für Internationale Zusammenarbeit (GIZ) for Africa) who were key editors of the technical report. pathways. During its first Phase (completed in June 2013),
technical and financial assistance, under the supervision of Ms Gigi Laidler served as the SANBI project administrator fundamental climate modelling and related sector-based
Dr Michaela Braun and Mr Zane Abdul, who also served with assistance from Ms Faslona Martin, Mr Nkoniseni impacts and adaptation scoping were conducted and
on the Project Management Team. Ramavhona who served as DEA project administrator synthesised. This included an analysis of climate change
and Ms Gwendolin Aschmann from GIZ who provided trends and projections for South Africa that was compared
DEA and SANBI would like to thank Department of
additional project management support. Ms Jaqui with model projections for the same time period, and the
Water (DWA) for their partnership in this work and in
Stephenson (Environmental Resources Management) and development of a consensus view of scenarios for three
particular Dr Smangele Mgqubai who served as the focal
Mr Dick Cloete (Media Directions) provided preliminary time periods (short-, medium- and long-term). Scoping of
point from DWA. Specifically, we would like to thank the
and final editing of phase 1 products respectively, and impacts, adaptation options and future research needs,
groups, organisations and individuals who participated and
Studio 112 conducted the layout. identified in the White Paper and guided by stakeholder
provided technical expertise and key inputs to the Climate
engagement, was conducted for primary sectors namely
Change Implications for the Water Sector technical
water, agriculture and forestry, human health, marine
report, namely Dr Guy Pegram, Ms Traci Reddy and Ms
fisheries, and biodiversity. This modelling and scoping
Naadiya Moosajee (Pegasys), Mr Konstantin Makrelov and
will provide a basis for cross-sectoral and economic
Mr Yogesh Narsing (the National Treasury and National
assessment work needed to develop plausible adaptation
Planning Commission), Dr James Cullis, Alice Change and
scenarios during Phase 2 (scheduled for completion in
Jacque Taljaard (Aurecon), Gerald de Jager and Jonathan
April 2014).
Schroeder (AECOM), Dr Adam Schlosser and Dr Kenneth
Strzepek (Massachusetts Institute of Technology [MIT]), Six individual technical reports have been developed
LTAS Technical Working Group members, and members to summarise the findings from Phase 1, including one
of the Climate and Impacts task teams. technical report on climate trends and scenarios for South
Africa and five summarising the climate change implications
for primary sectors, water, agriculture and forestry, human
health, marine fisheries, and biodiversity. A description
of the key messages emerging from the LTAS Phase 1 has
been developed into a summary for policy-makers; as well
as into seven factsheets constituting the LTAS Climate and
Impacts Factsheet Series.
i Dr S K Mgquba, Climate Change Research and Advice, Dept of Water Affairs 185 Schoeman Street, Pretoria, 0001 • Tel: 012 336 7183
• Fax: 012 336 7399 • Cell: 082 654 0315
ii Mr Shonisani Munzhedzi, Department of Environmental Affairs, Climate Change Branch, Chief Directorate Adaptation
• Tel: +27 (0) 12 395 1730 • Cell: +27 (0) 76 400 0637 • email: SMunzhedzi@environment
8 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 9
Report Overview
This technical report presents the LTAS Phase 1 findings development in South Africa, and aspects of the WGDF Chapter 2 (Climate change impacts on the water sector)
for the water sector in South Africa. It references existing described in section 1.1.1 are now incorporated into the synthesises results from recent climate change impact
South African research to describe the status quo for finalised NWRS2 as core strategies. It is recommended assessments in relation to hydrology, water quality, water
water resource planning in South Africa, including the that the final NWRS2 (now available on the Department of use and water supply systems. This includes climate
extent to which climate change is considered in the Water Affairs (DWA) website: www.dwaf.gov.za) be read change and hydrological modelling results for the water
existing water resources planning framework, as well to complement certain sections of the technical report. sector, namely impacts on national runoff, water resource
as the potential effects of climate change on the water In terms of its mandate and the strategic imperative system yields and high risk hydrological zones comprising
sector. This includes an analysis of existing water resource under the National Climate Change Policy, the DWA is reconciliation study areas.
planning tools, originally developed to address demand in the process of developing a climate change adaptation
Chapter 3 (Adaptation response options) describes
growth and climate variability, in the context of future strategy for the water sector. This is being done in two
adaptation responses for the water sector against the
climate change requirements. These tools include phases, beginning with an Assessment Phase, which will
backdrop of the water resources planning framework
reconciliation studies (one of the key tools used in South then inform the Strategy Development Phase.
presented in Chapter 1, Section 1.1. This includes
Africa for assessing water use and future requirements)
Annex 1 of this technical report provides key background summarising specific interventions for each level and
and water strategy policy documents. This technical
detail on reconciliation studies and the All Towns Strategies focus area within the framework, as well as highlighting
report summarises climate change impacts, adaptation
which are one of the central tools for water resources priority functions that would be beneficial for the
response options and future research needs for the
planning at infrastructure system level, and are likely to DWA, and incorporating climate change adaptation in
water sector based on the results of relevant past and
be critical elements of a future national response capacity. reconciliation studies and other water resource planning
current research, including the draft National Water
These studies and strategies are updated annually with the tools. An overview of the adaptation measures proposed
Resource Strategy 2 (NWRS2), the National Water
latest information provided on the Department of Water in the Draft Climate Change Adaptation Strategy for the
Adaptation Strategy process, and new impact modelling
Affairs website (www.dwaf.gov.za). The information water sector is also included.
for annual and seasonal runoff under both unconstrained
and constrained pathways from recent modelling work presented here is based on the data available between
Chapter 4 (Research requirements) highlights areas in
conducted by the Treasury and the National Planning April 2012 and March 2013.
which research is required for supporting the development
Commission (Treasury and NPC, 2013). of tools, approaches and case studies that inform water
A brief description of each chapter of the technical report
is provided below. planning in the context of long-term climate change.
The NWRS2 defines the strategic direction for water
management in South Africa over the next 20 years, Chapter 5 (Conclusion) concludes the report highlighting
Chapter 1 (Strategic water planning in South Africa)
but also the focuses on water priorities for the next the scope of LTAS Phase 2 in exploring the socio-economic
provides an overview of water resource planning in South
five years (2013–2017). At the time of developing this implications of a range of possible climate-water futures
Africa including at national level, water resource system
technical report the draft NWRS2 had been completed in South Africa.
level, water management area (WMA)/catchment level as
and was under public review. The final NWRS2 was
well as at the sub-catchment/municipal level. The chapter
approved by the Minister in June 2013. Substantial changes Annex 1 (Review of existing reconciliation studies
has a focus on reconciliation studies, which are the central
were made to the NWRS2 based on the public review for South Africa) provides a full description of existing
tools used at water resources infrastructure system
process and this should be borne in mind when reading reconciliation studies with a focus on area of supply,
level, and includes an assessment of the use and future
this technical report. In particular, the Water for Growth hydrological record, assumptions of the study, current
requirements for water in South Africa and how these
and Development Framework (WGDF) described in and future water requirements, water resource planning
requirements can be “reconciled” with the available
Section 1.1.1 (National planning) of this report, although and climate change considerations. This is linked to the
sources through various strategies over the next two to
approved by Cabinet, has not been finalised (gazetted). summary presented in Chapter 1.
three decades. The chapter provides a summary of the
The NWRS2 has adopted this framework as a primary
approach and progress of existing reconciliation studies Annex 2 Provides an indicative finer scale case study on
tool for management of water resources for growth and
to date, with a full description presented in Annex 1. climate change impacts on water resource system yields.
10 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 11
Executive Summary
Because of South Africa’s generally arid to semi-arid guidance on the likely range of change in rainfall and Orange River region. Specific areas of high risk, where flexible and robust infrastructure planning, resources
climate, rainfall and river flow are unpredictable in time temperature that must be further translated using cumulative negative climate change impacts are likely directed at maintaining and rebuilding ecological
and unevenly distributed in space, with only 12% of the hydrological modelling approaches of projected impacts to occur (including increased evaporation, decreased infrastructure in vulnerable systems, institutional
land area generating 50% of potentially available surface on surface water flows and availability. Based on LTAS rainfall and decreased runoff), include the southwest oversight to ensure water-related institutions build
water resources. Decadal rainfall variability also results Phase 1 findings (see climate trends and scenarios of the country, the central-western parts and to some adaptive management capacity, effective information
in extended periodic dry and wet periods across the technical report), South Africa’s climate future up to extent the extreme north. Under all four future medium management and maintenance of monitoring and
country. Surface water resources were already over- 2050 and beyond can be described using four fundamental and long term climate scenarios a higher frequency of evaluation systems, and sustainable and locally accessible
allocated by the year 2000 in five of the nineteen water climate scenarios at national scale, with different degrees flooding and drought extremes is projected, with the financial management.
management areas. of change and likelihood that capture the impacts of global range of extremes exacerbated significantly under the
Research and focused monitoring is required to support
mitigation and the passing of time. unconstrained global emissions scenario.
Demand for water is expected to increase with economic the development of tools, approaches and case studies that
growth, increased urbanisation, higher standards of living, 1. warmer (3°C above 1961–2000) and drier,
changes can be observed with increasing certainty, and
Current national water planning contingencies provide with a substantial increase in the frequency of Key decisions in development planning would benefit
adopt flexible planning to allow appropriate responses as
assurance of water supply (based on surface water drought events and greater frequency of extreme from considering the implications of a range of possible
conditions change.
resources) from 91% (for agricultural use) up to as high rainfall events. climate-water futures facing South Africa. Under a wetter
as 99.5% for key strategic uses under historic patterns Adaptation response strategies for the water sector future scenario trade-offs in water allocation between
of rainfall variability. Groundwater resources are not Projections for national runoff range from a 20% reduction sectors are likely to be less restrictive, providing greater
can usefully be identified at distinct governance levels.
currently fully integrated into the national water strategy, to a 60% increase by as early as mid-century based on scope for urban-industrial economic growth and water
At national scale, the development of a strategic intent
though these currently provide about 10% of national an unmitigated global emissions pathway. However, if provision for an intensive irrigated agricultural production
and an enabling framework for adaptation would help
needs, being primarily used for irrigation. A key concern global emissions are constrained to stabilise at 450 ppm model. Under a drier future scenario significant trade-offs
to ensure a coherent national response. At sub-national
for the water sector is, therefore, whether future rainfall CO2 , these changes are projected to lie between a 5% are likely to occur between developmental aspirations,
or system scale, key institutions could usefully engage
variability will exceed patterns based on the historical decrease and a 20% increase in annual runoff. Sub- particularly in terms of the allocation between agricultural
in prioritising and allocating resources to adaptation
record. Current modelling of future climate is uncertain nationally, projected changes range from increases along and urban-industrial water use, linked to the marginal
interventions that adequately reflect the conditions at
with respect to rainfall variability and seasonality change, the eastern seaboard and central interior to decreases in costs of enhancing water supply. These constraints are
that scale. At sub-catchment or municipal scale, the design
but more certain with regard to warming projections. much of the Western Cape. Areas showing highest risks most likely to be experienced in central, northern and
of local implementation actions would be facilitated by
Consequently, a scenario-based approach is a viable way of extreme runoff related events include KwaZulu-Natal, south-western parts of South Africa. This scenario has
responding to local challenges, resources and capacities.
forward with respect to exploring adaptation options parts of southern Mpumalanga and the Eastern Cape. significant social, economic and ecological consequences
for this sector and the cross-sectoral and economic Other areas show neutral to reduced risk of extreme The following priority functions would be beneficial to through restricting the range of viable national
implications. Climate modelling approaches provide runoff events, with the exception of the central and lower the DWA: policy review for enabling flexible frameworks, development pathways.
12 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 13
1. Strategic Water Planning in South Africa
1. Strategic water planning in South Africa
The water sector has a multifaceted planning regime which 1.1 National planning
will be central in the development and implementation of National planning provides the strategic framework for
adaptive responses to climate change. South Africa has a local planning. The overarching plan is the National Water
number of levels of water planning as indicated in (Figure 1). Resource Strategy (NWRS). This strategy is required by
Vertically, planning is aligned from national to local level, the National Water Act (Act 36 of 1998) and defines
with consistent legal requirements and, as the figure the strategic direction for water management in South
indicates broadly, the delegation of responsibilities from Africa over the next 20 years, but also the focus on
national level down to local and sub-catchment levels. water priorities for the next five years. Under the NWRS
Horizontally, there is cooperation between the three there are a number of national thematic plans such as the
broad sectors of water resources management, water National Climate Change Strategy for Water Resources
resources infrastructure, and water services. (WCCS) and the Ground Water Strategy (GWS).
National water services planning is focused largely on
National Water Resource Strategy Figure 2. Water availability (blue) and use (green) (DWA, 2009b).
(DWA) financing and monitoring, and on providing a framework
National Water Infrastructure Framework with norms and standards for local government to provide
National WR Thematic Plans (DWA) (DWA)
Climate; Groundwater; Pricing; water services in terms of its Constitutional Mandate. that the DWA should focus on adaptation responses, as
Alien clearing etc the mitigation potential in the sector may be relatively
1.1.1 Water for Growth and small (the water sector contributes 1% to total national
Water Catchment Management Development Framework emissions), despite the fact that adaptive responses such
Resource Strategy (CMA)
The draft Water for Growth and Development Framework as desalination have mitigation implications through their
System Reconcilliation Studies (WGDF), version 7, was released in 2009 and is described energy demands, and that national mitigation responses
(DWA) by the National Climate Change Response White Paper as will have implications for the water sector.
Feasability Study
the long-term tool for the water sector to deal with climate
Water (DWA) Water Board The framework does not describe an integrated national
change. The WGDF although approved by Cabinet, has
Management Infrastructure approach to the effects of climate change on water
Internal Strategic and Business Plans not been finalised (gazetted). The framework describes
Area resources, and provides a suite of broad options similar
Catchment Perspective (DWA) the current water resources as being insufficient to satisfy
to those described in the National Climate Change
Management Strategy the projected increase in demand, as indicated in Figure 2,
(CMA) Response White Paper. The issue of extreme events such
and proposes a number of high-level recommendations.
as droughts and floods is only implicitly addressed with
Catchment WR One such recommendation is to increase the supply of
Plans reference to potential risks and threats.
Sub- (DWA/CMA/LG)
Water User Association water by diversifying the water mix using desalination in
Business Plans (WUA) coastal areas and recycling in inland areas as a strategy Box 1 describes the three options for the water sector
catchment/ All Town Strategies to increase water security. The framework describes the to deal with climate change from the framework, which
Municipal (DWA) Water Services
Development Plan threat of climate change on water resources, and proposes is yet to be finalised and published by the DWA.
(WSA)
Water Water Water
resources resources services
management infrastructure
Figure 1. Water resources planning framework in South Africa (light blue – management; blue – infrastructure; Orange – services)
14 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 15
1. Strategic Water Planning in South Africa
consideration of further enabling strategies, addressing The strategy not only recognises the need to ensure that
Box 1. Options for dealing with climate change Box 2. Core climate change objectives of NWRS2 issues such as catchment management, to enhance the groundwater should be protected, but it should also form
To address the potential risks and threats posed by climate Integrating climate change considerations in the short-, planning of hard infrastructure to adapt to climate change. part of the climate change adaptation strategy to assure
change with respect to water security, the following medium- and long-term water planning processes: the continuity of water supplies.
actions should be seriously considered: 1.1.3 Climate change strategy for
• Implementing the best catchment and water water resources
• Develop a water sector response management practices to maximise the degree Currently, the DWA is working on a climate change
strategy comprising adaptation plans and of water security and resource protection under strategy for South Africa’s water resources. The first
mitigation measures changing climatic conditions. part of the process, which is now complete, examines
• Stimulate a shift in focus from climatic • Reducing the vulnerability and enhancing the the status quo of water resources in South Africa and
prediction and mitigation to response and resilience to water-related impacts of climate the additional dimension climate change adds to various
adaptation options. change in communities/sectors at greatest risk. aspects of managing water resources.
• Focus on those WMAs or catchments likely to • Providing human, legal, regulatory, institutional,
face the greatest risk of water shortages or with The base assumption about the water impacts of climate
governance and financial resources and capacity to
high runoff and erosion potential, and develop an change informing the strategic responses is that South
deal with the long-term effects of climate change.
appropriate and reliable understanding so that Africa’s water resources are highly developed, highly
• Undertaking focused monitoring and research in Figure 3. Groundwater exploitation potential (National Groundwater
risk and disaster management plans can be drawn stressed and suffer from a certain level of degradation.
order to ensure the efficacy of water adaptation Strategy, 2010)
up and implemented. High water demand and high levels of pollution from
approaches over the long-term.
a variety of sources have added to the complexities The strategy recognises that groundwater is not
of a fundamentally high risk hydrology. Thus climate consistently managed or assessed as with other sources
1.1.2 National Water Resource Strategy The enabling strategies that have been identified to enable
change adds a layer of increased stress onto an already such as surface water potential, and may not feature
the implementation of the NWRS2 fall broadly under the
The National Water Resource Strategy 2 (NWRS2), stressed system. A key message is that better optimised prominently in water resource plans. As a result,
following headings:
required by the National Water Act (Act 36 of 1998), management of the current situation would be beneficial more expensive options may be implemented where
defines the strategic direction for water management in • Water finance and funding in addressing the longer-term impacts of climate change. groundwater may be a viable and more cost effective
South Africa over the next 20 years and the focus on • Water sector capacity building option. A key advantage of groundwater in a climate
water priorities for the next five years (2013–2017). 1.1.4 Groundwater management strategy change context is that it is buffered to some extent from
• Monitoring and information
The National Groundwater Strategy, completed in rainfall variability, and impacts may have a slower onset
The NWRS2 assumes that climate change will increase • Research and innovation
2010, recognises the importance of groundwater as an as the replenishment of groundwater is controlled by
the pressure on already stressed water resources, and
Unfortunately, climate change objectives feature explicitly underutilised water resource (DWA, 2010c). The strategy long-term climatic conditions.
thus that there is a crucial requirement for the effective
management, use, allocation and re-allocation of only for monitoring and evaluation, leaving significant aims to quantify groundwater as a resource, as indicated
available water resources. The strategy further sets out gaps in elements of the strategy that are necessary for a in Figure 3, and provide direction for its management.
particular climate change objectives which are required long-term, sustainable adaptive response under climate
Currently, about 10% of South Africa’s water resources
to be integrated into the short-, medium- and long-term change. The National Climate Change Strategy for
are sourced from groundwater. The sectoral use of
planning for water resources as indicated in Box 2 below. Water Resources (see below) could also benefit from
groundwater is indicated in Figure 4 below, where use
for irrigation accounts for the most groundwater usage.
16 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 171. Strategic Water Planning in South Africa
methods either singly or in combination to remove A number of thematic plans also exist at the system through various strategies for the next two to three
alien species. Figure 5 below indicates priority areas for planning level, which are commissioned on an “as needed” decades. The main aim is to determine when the next water
clearing. This is currently being revised. basis and tend to be specific to a single system, such as the infrastructure system would be required and when it should
acid mine drainage (AMD) plans which affect particular be built. Adaptation is inherent in the planning approach
There are distinct benefits to using WFW as an adaptation
water systems in South Africa. These tools could also but it does not take a long-term strategic perspective.
measure, especially as climate change exacerbates
usefully be further developed to support climate change These studies address:
water scarcity. However, resources will be required
adaptation responses.
for ongoing management to keep areas alien free and • Future water requirement scenarios for and within
to rehabilitate natural vegetation to ensure that water the metropolitan area.
1.2.2 Reconciliation studies
services are maintained. • Water resources and other interventions that
Water resource planning requires an understanding
could add to water availability.
of the key drivers of water demand and how different
development futures will impact on water resource • Possible methods for reconciling the requirements
Figure 4 Groundwater use per WMA (Groundwater Strategy, 2010)
availability and use. The most common approach to for water with the available resources.
The report recognises that artificial recharge is a incorporating different development futures in water • Recommendations on the development and
groundwater management technique that may play an resource planning is to firstly understand the trends implementation of required interventions
increasing role in maintaining South Africa’s water security. in current water use and to quantify the available and actions.
Artificial recharge is the transfer of surplus surface water resources, and then to account for future demand under • Monitoring and updating of the strategies into
underground by injecting it into aquifers through boreholes. different scenarios. the future.
The advantages include lower evaporation losses, which
will become especially critical as higher temperatures The key drivers of water use are to a large extent linked to The potential key strategies for climate change
increase evaporation of stored surface water. population growth rates, and water use in specific sectors adaptation include:
such as industry, domestic use and irrigation. For example,
The strategy recognises the need for more research into Figure 5. Map for removal of invasive alien species based on a prioritisation in South Africa rapid growth in urbanisation, coupled with • Water conservation and demand management
the effects of climate change on technical issues such as model (Le Maitre et al., 2012) economic development in general, will increase water • Re-using water
groundwater recharge. There is limited understanding of demand. This, however, depends on the local context, • Using groundwater
the origin, recharge and availability of groundwater. This is 1.2 Water resource system planning for example, in the Lephalale water supply system future
• Desalinating seawater (applicable to coastal areas)
further hampered by the reduction in both skills and water demand will be driven largely by industrialisation
South Africa has developed a sophisticated methodology • Building dams
infrastructure for monitoring groundwater. Furthermore, as a result of energy production and mining, whereas in
to consider historical climate and hydrological variability
groundwater quality under climate change and the effects the Western Cape rapid urbanisation will drive future • Transfers between dams
in water resources infrastructure planning. The main
of long-term droughts on groundwater need further water demands. • Rehabilitating catchments by clearing invasive alien
tools for system planning are reconciliation studies, which
research to improve understanding. plants and restoration
guide water infrastructure planning and comprise detailed The general trend has been to construct different
planning and operational considerations, informed • Harvesting rainwater
scenarios that can be synthesised into a low water demand
1.1.5 Alien invasive species clearing by assumptions of water demand trajectories. These • Changing water use
scenario and a high demand scenario These are based
The Department of Environmental Affairs is leading a studies are supported by the application of a number of • Improving management and operations.
either on population growth rates, or water demand in
multi-departmental process to remove invading alien plant modelling tools that will be central in assessing adaptive key sectors of the economy that are expected to grow
species under the “Working for Water” (WFW) banner. responses under future climate change. An overview The planning of water resources requires the consideration
with significant water requirements.
Removal of alien invasive species has multiple benefits, of the reconciliation study method and its focus areas of many uncertainties, including the extent and nature of
including maintaining natural biodiversity, improving water is described in Annex 1, as these could usefully form a Water resource reconciliation studies involve an assessment future requirements, and knowledge of both rainfall and
security and creating jobs. There are currently 300 active central pillar of adaptation responses to climate variability of the use and future requirements for water, and how runoff; knowledge that slowly improves as the historical
programmes using chemical, mechanical and biological and change. these can be “reconciled” with the available sources record grows.
18 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 191. Strategic Water Planning in South Africa
Climate change exacerbates climate variability, which in and/or climate change has been incorporated into the water supply to future power stations to avoid duplication 1.2.2.2 Prioritisation criteria
turn increases the uncertainty around water resource assumptions made for the different scenarios and the or omission. Projections of future requirements are When looking at the development pathways for the
planning. In order to assess the impact of climate change, water demand and supply projections. Reconciliation made for the period to 2035, and then extrapolated to reconciliation studies a number of decisions need to be
knowledge about the components of the hydrological studies (and the all towns strategies – see Section 1.1.4) 2050. Instead of a spectrum of high and low scenarios, a made, for example, new schemes or interventions have
cycle that are impacted on by climate and determining are updated annually with the latest information provided reference scenario was selected. The expected growth been introduced only when dictated by the growth in
trends distilled from historical records become crucial. on the DWA website (www.dwaf.gov.za). The information in water requirements is predominantly in the urban, water requirements. These developments would then
The key components of the hydrological cycle are: presented here is based on the data available between industrial, mining and power generation sectors. There
be prioritised and phased for each area according to the
April 2012 and March 2013. were no growth projections for irrigation developments,
• Changing precipitation patterns following criteria:
unless otherwise stated in the NWRS (DWA, 2010a).
• Increasing atmospheric water vapour 1.2.2.1 Approach to the Reconciliation Studies • Ranking of options according to the unit cost of
• Changing temperature patterns such as increasing It should be noted that while the possible impacts of
There are thirteen reconciliation studies for South Africa. In water, with the highest ranking afforded to the
evaporation climate change are taken into account during the detailed
addition to these, the all towns strategies are reconciliation option with the lowest URV.
planning of water resources developments, specific
• Changes in soil moisture and runoff studies for smaller water supply areas. Currently nine of • When two options have the same URV, the
provisions for climate change may not have been included
• Changing water quality conditions. the bulk water studies have been completed. All 914 all in the reconciliation studies. This is further explored in one with the lowest unit energy requirement is
towns strategies have also been completed. the review of the case studies summarised below in Table prioritised.
1 with full details provided in Annex 1. It should also be • Options to meet the growth in water
In general, the assessments of water availability were based
noted that limited detailed information on the potential requirements would be phased in by first using
on current infrastructure, current levels of development
impacts of climate change on hydrology was available when the highest ranked option, and then those with
and accurate accounting for surface water, groundwater,
the existing reconciliation studies were developed. DWA progressively lower rankings.
return flows and inter-basin transfers. Implementation
has indicated that the methodology will be revisited with • Should the highest ranked scheme not be able
of the ecological reserve and availability of water from
the research and information that has been generated to deliver water in time (due to its status in
desalination was also considered. It should be noted that
during the National Water Adaptation Strategy process. the development cycle), then the next-ranked
water conservation and water demand management is the
priority strategy in all large reconciliation areas, and in the scheme that could be implemented in time would
The unit cost of water is the basis for comparing the
all towns strategies (further described in Section 1.1.4). be used.
various augmentation options that inform the development
The specific measures differ from area to area depending pathway. For comparative purposes, the marginal cost was
on the local context. expressed in terms of unit reference value (URV) as a The development of new water resources infrastructure
Figure 6. Key economic areas in relation to existing water supply system
studies (RSS – reconciliation strategy study) first order economic indicator. It should be noted that is a complex and time-consuming process that
DWA (2010a) provides an overview of the future water
the URV does not consider the costs of rehabilitation and typically takes more than a decade from inception to
In the reconciliation strategies for the metropolitan areas, resources and the water balance situation in South
maintenance of the catchment. The energy requirements commissioning. For larger and more complex projects
the possible impacts of climate change on available water Africa, which should serve as input to national strategic
for the various options is another key variable, therefore, with environmental and political sensitivities lead times
are included in future scenarios to ensure timeous study spatial and sectoral development planning. This includes
the marginal energy costs were also determined for use may be more than two decades. It is essential therefore
of augmentation options. Adaptation measures can then assessment of the remaining potential for water resource
in the URV calculations. It should be noted that growth to identify development needs and undertake preparatory
be introduced when they become necessary. An example development in South Africa and the means to extend
in future water requirements as well as the sizing and work well ahead of the time a project needs to deliver
would be the predicted drying of the west coast and the the utility of the resources, all with associated costs and
scheduling of a development option can have a major water. Figure 7 below shows the typical programme for
effect this would have on the water supply to Cape Town. estimated energy requirements. The report provides a
influence on the URV (DWA, 2010a). water resources development.
clear perspective on water resources and future water
Presented below and in Annex 1 is a high level assessment requirements, and scenarios on how these could be
of the reconciliation studies that have been conducted in reconciled for various key areas in the country. Special
South Africa, looking specifically at how climate variability care was taken over inter-basin transfers and provision of
20 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 211. Strategic Water Planning in South Africa
Typical Programme for Water Resource Developments Table 1. Summary of reconciliation studies to date
1 2 3 4 5 6 CLIMATE CHANGE HYDROLOGY
NO STUDY AREA OF SUPPLY PROGRESS
CONSIDERATIONS CONSIDERATIONS
1–5 years 1–3 years 2–4 years 2–5 years 2–6 years 4–8 years
1 Algoa Nelson Mandela Bay Completed in The study highlighted the need to Data were used for the
(1) (2) (3) (4) (5) (6)
Municipality (NMBM), several 2011 monitor the impacts of climate change period between 1927 and
Feasibility Decision Support Design/ Construction/ smaller towns within the and conduct an impact assessment study 1991. There were large
Reconnaissance Phase Pre-feasibility Phase
Phase Phase Documentation Phase Implementation Phase Kouga Local Municipality to determine the expected regional discrepancies between
• Detail investigation and the Gamtoos impact of climate change on the Algoa the above period and
and assessment Irrigation Board. water supply system (AWSS) water recent hydrology. Further
of best options(s), balance. It was assumed that climate investigations are underway.
• Formalise change would reduce the yields by 10%.
• Preliminary sizing and • Environmental
• Needs identification institutional • Procurement
investigation configuration approval 2 Amatole The system supplies the Completed in Climate change was considered, but The initial analysis looked
arrangements
(technical, Buffalo City Municipality, 2008 was not incorporated into the water at the period from 1920 to
environmental including East London, King balance reconciliation. 1996. This was extended
and cost) Williams Town, Bisho, and and a hydrological record
• Identification part of the Amathole District from 1920 to 2003
• Identify best Municipality area. was used.
and selection • Recommendation • Reserve • Resettlement and
options for detail • Secure funding
of possible of project determination compensation 3 Bloem This system provides most Completed in No climate change considerations have Assumed data records to
study
interventions of the water required by the 2012 been made. start from the 1920s.
• Procurement towns located within the
• Public involvement • Construction Mangaung Metro Municipality,
procedures
• Initial funding • Engineering design namely Bloemfontein,
• Impounding and Thaba Nchu, Botshabelo,
and institutional and construction
commissioning Dewetsdorp, Reddersburg,
arrangements documentation
Wepener, Edenburg and
• Some optimisation Excelsior.
• Decision to
4 Crocodile West This study covers the Completed in No climate change considerations were The simulated flow data
implement northern areas of Gauteng, 2010 found in the report. for the Crocodile (West)
Notes: 1) Numbers in brackets indicative of average periods. the platinum mines, other River Catchment covers
2) Some of the activities typically extend over more than one phase. developments around the hydrological record for
3) D
etermination of the Reserve should be independent from any specific project development. However, where the Reserve has not Rustenburg and Brits and 1920 to 2003.
previously been determined, it may be included under the development programme. It is therefore not restricted to a specific phase. further north to Thabazimbi
and large-scale energy-
Figure 7. Water resource development diagram (DWA, 2010a) related developments
that are planned for the
Waterberg coalfields in the
1.2.2.3 Review of existing reconciliation studies vicinity of Lephalale.
Table 1 provides a summary of the progress of reconciliation studies were developed, the DWA focused on developing 5 KwaZulu- This study looks at the area Completed in The study notes that climate change
Natal Coastal between Pietermaritzburg, 2010 should be monitored and that current
studies to date, with an indication of the way climate change crude scenarios only where there were indications that the Metropolitan Durban, Kwadukuza and models show no reduction in rainfall
Amanzimtoti. It includes the patterns, but there may be variability.
has been considered. See Annex 1 for a full description yield could decrease. This included the Western Cape and eThekwini Metropolitan, Umgeni Water is in the process of
of existing reconciliation studies with a focus on area of Algoa areas. These scenarios were based on the assumed Msunduzi and Illembe conducting a study on the impacts
municipalities. that climate change could have on the
supply, hydrological record, assumptions of the study, drop in yield and ensured that appropriate interventions water resources. These results are not
current and future water requirements, water resource were brought into the planning cycle. This methodology yet available.
planning and climate change considerations. As limited will be revisited with the research and information that 6 Luvuvhu & The whole of the Luvuvhu In progress, No climate change considerations
Letaba and Letaba WMA and parts completion date thus far.
detailed information on the potential impacts of climate has been generated during the National Water Adaptation of the adjacent WMAs. is May 2013
change on hydrology was available when the reconciliation Strategy process. 7 Mbombela The municipal area straddles In progress, No climate change considerations
Municipal Area the Sabie and Crocodile River completion date thus far.
catchment is 2014
8 Mhlatuze Mhlatuze Local Municipality, In progress No climate change considerations
comprising Empangeni, thus far.
Ngwelezana, Nseleni,
Esikhaweni and a number of
rural villages.
22 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 231. Strategic Water Planning in South Africa
Table 1. Summary of reconciliation studies to date 1.3.1 Breede-Overberg Catchment
NO STUDY AREA OF SUPPLY PROGRESS
CLIMATE CHANGE HYDROLOGY Management Strategy. • Monitoring changes and developing information
CONSIDERATIONS CONSIDERATIONS
The Breede-Overberg CMA (BOCMA) is located in the to indicate expected change and variability
9 Olifants This study covers the entire Completed in No climate change considerations Assumed data records to
Olifants WMA and the 2012 were made. start from the 1920s. Western Cape. A scenario based on a median climate is critical.
adjacent areas of Polokwane
and Mogalakwena, which are
response drawn from a set of climate projections for 2050 • As information is better understood, key natural
supplied from the Olifants. shows climate change leading to progressive drying with ecosystems, infrastructure, and institutional
10 Orange The study consists of the In progress, No climate change considerations an increase in extreme rainfall events. developments should be identified, prioritised,
Upper and Lower Orange completion date thus far.
River WMAs, while also is 2014 and steps taken toward building resilience in the
considering all the tributary identified areas.
rivers and transfers affecting
the water balance of the • While BOCMA will play a lead role in this action
system. This core area forms
part of the Orange-Senqu
collaboration, primarily with the DWA and the
River Basin. Provincial Government, will be necessary for
11 Vaal This study includes most of Completed in No climate change considerations. Assumed data records start natural ecosystem and infrastructural resilience,
Gauteng, Eskom & Sasol’s 2008 from 1920s
industries in Mpumalanga, and coordination with additional institutions will
North West and Free State, be required for building institutional capacity.
gold fields around Welkom,
mines in the Northern Cape, • Does this include increasing the efficiency of
Kimberly and small towns
along the river.
water use?
12 Western Cape This study looks at the Completed in The first strategy noted that climate Long-term stream flow,
City of Cape Town, certain 2007 change should be monitored. rainfall, water quality The main objective of climate change adaptation and
Overberg, Boland, West The revised strategy looked at a and climate records are
disaster risk management is to develop and improve
Coast and Swartland scenario with a 5% decrease in yield available for 80 years. Figure 8. Location of the Breede-Overberg WMA (DWAF)
towns and irrigation along over 25 years. resilience to hydrological variability and disaster risk
the Berg, Eerste and The catchment has a strongly water-dependent economy through an improved understanding of trends and
Riviersonderend rivers.
13 All Towns This study includes over In progress based on intensive irrigated agriculture, and therefore the events, their impacts upon the social economy and the
800 reports and is available strategy focuses on two components, namely building necessary strategic responses.
either per province, per
district municipality or per climate change resilience and ensuring climate change
local municipality. is considered in disaster risk management. While the Achieving this includes:
response is not comprehensive, it indicates the need
1.3 Water management area/ for more research and better understanding of climate • Strengthening information acquisition and
catchment planning change in order to provide a more coherent approach. assessment related to climate variability and
The response is described in Box 3 below. change and development (trends).
While the management of water resources and adaptation management of strategies. Furthermore, the CMAs have
to climate change happens through all levels of planning, been amalgamated from 19 to 9, and once the amalgamated • Building institutional flexibility for resilience.
it can be facilitated directly at catchment level, the scale CMAs are functional catchment management strategies Box 3.The objective for climate change resilience • Mainstreaming water and cooperating with
at which the effects of climate variability and change play (CMSs) will need to be developed. The CMA and its CMS in the catchment: provincial and local disaster bodies.
out on a micro-level. However, catchment management represent an opportunity to support adaptation, with Make robust water resources management decisions that • Assessing water disaster risk and developing
agencies (CMAs) are still being developed, with only two inputs from catchment forums and water users’ associations build natural ecosystem, infrastructural and institutional a WMA flood and drought strategy aligned to
being functional. There are capacity constraints at this (WUAs) at a more localised level that could help implement resilience to climate variability and change. national disaster management.
local level to providing the necessary implementation and the risk and disaster management plans for the catchment.
24 LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR LTA S: CLIMATE CHANGE IM PLIC ATION S FOR THE WATER S ECTOR 25You can also read
