RISK-BASED OPERATIONAL WATER MANAGEMENT THROUGH IMPROVED HYDROLOGICAL UNDERSTANDING TO AUGMENT IWRM INSTITUTIONAL CAPACITY IN THE INCOMATI E.S. Riddell*a, A.M.L. Saraiva-Okellob, P.Van der Zaagb, G.P.W. Jewitta, S. Uhlenbrookb, B. Jacksonc, T.K. Chettya.
a
School of Bioresources Engineering & Environmental Hydrology, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, South Africa b
UNESCO-IHE, Department of Water Engineering, PO Box 3015, 2601 DA Delft, The Netherlands c
Inkomati Catchment Management Agency, P/Bag X11214, Nelspruit, 1200 Floor 3, Caltex Bldg, 32 Bell Street, Nelspruit, 1200 * Corresponding author:
[email protected]
Abstract
This paper follows our proposal of the project, ‘Risk-based Operational Water Management for the Incomati Basin (RISKOMAN)’ presented at the 11 th WaterNet Symposium, Victoria Falls, Zimbabwe, October 2010. This manuscript details our refined conceptual approach and the context of water resource management (WRM) in this heavily committed international basin. Details of the development of an improved hydrological understanding of the Incomati Basin are discussed, with the identification of variability in the basins hydrological fluxes and managerial drivers, most notably through novel approaches in remote sensing, hydrochemistry and hydrological modelling, particularly with respect to blue-green water accounting. Moreover there is a discussion of how these approaches will facilitate tractable use in the present and future decision making requirements for optimal management of the basin’s water resources given the status-quo of the basin at present. This is within the context of devolved WRM responsibilities in South Africa and it’s commitment to transboundary water sharing initiatives with its neighbours Mozambique and Swaziland. These objectives will be achieved through the identification of hydrological information requirements and key knowledge gaps to the water resource managers in the basin, such as the Inkomati Catchment Management Agency and other parties. There is a discussion on how RISKOMAN is achieving these aims through the establishment of conceptually simple, scientifically robust and geographically explicit decision-making tools through interactive social learning with the guiding governors of WRM in the basin. Keywords: adaptive management; basin closure; green- and blue-water; optimal allocation policy; water economics
1.
Introduction
Catchment closure, or the process by which water resource demands approach or exceed the available supply are by definition human-induced. These are manifested through social, economic and political supply orientated strategies and constrained by a disregard for the natural biophysical character supplying water to the catchment in question (Molle et al , 2010). The Incomati6 Basin (Figure 1) is a case in point, where the mean annual runoff is generated in the upper part of the three sub-basins; the Komati-Lomati, Crocodile and Sabie-Sand, the general picture is one of a closing basin with some particularly water stressed regions within them (Waalewijn, et al 2005). This closure is largely due to upstream agroforestry streamflow reduction activities and downstream water demands across the established and emerging agricultural sectors, but expanding municipal demands also. Moreover environmental water and basic human needs requirements are also key factors in this demand, and in South Africa at least these are legislated for in the interests of sustainability under the National Water Act 1998, but due to the presence of iconic conservation areas and under-serviced historically disadvantaged communities in the basin there are added imperatives to meet these requirements. Furthermore, complexity arises in the Inkomati due to South Africa’s requirements as an upstream state to meet prescribed cross-border flows into Swaziland and Mozambique.
The significant economic, social, and potential environmental costs of structural responses to the risks inherent in an uncertain hydro-climatic regime that characterises the Incomati basin, such as the construction of new dams, call for the development of non-structural alternatives such as dynamic reallocation and financial compensation through market-like transactions, option contracts and insurance mechanisms (Booker and Young, 1994; Characklis et al., 1999).
Up until the early 1990s structural responses to the water allocation problem were confined to national boundaries often fostering distrust and confrontation between the three neighbours. However with the emergence of democratic changes in the region during the 1990s the Incomati status-quo shifted to one of mutual co-operation, although water-sharing may still be somewhat delicate given the socio-economic growth in the basin (Carmo Vaz & van der Zaag, 2003). Thus the Incomati now finds itself in an era of scarperation – which describes scarcity as being a significant incentive for co-operation among parties sharing an international river basin (Dinar et al, 2006). Furthermore, the decentralisation of water resource management from national planning to local Water Management Areas (WMAs), by removing the typical command-and-control structures should engender more efficient, effective and sustainable solutions to water resource management (Rogers, 2006). As a result there are now organisations with devolved powers such as the Inkomati 7 Catchment Management Agency (ICMA), Komati Basin Water Authority (KOBWA) and Administração Regional de Áquas do Sul (Ara-Sul) and grass-roots representation amongst various Water User Associations (WUAs). Significantly this scarperation requires a step-wise integration of the international water allocation issues, as found in the Progressive Realisation if the Inco-Maputo Agreement (PRIMA).
6
Incomati – defined here as the basin that encompasses the nations of Mozambique, South Africa and Swaziland 7 Inkomati – Spelt with a ‘k’, the part of the basin within South Africa
Figure 14.
The Incomati river basin in Southern Africa (Source: JIBS, 2001)
Nevertheless since all sectors in the Incomati require a spatially and temporally variable water allocation, it is imperative that holistic and dynamic approaches be taken at the basin scale in order to reconcile the principles of efficiency and equity (Dinar et al, 1997; Molle et al., 2007). This is necessary in order to mitigate against negative externalities transmitted downstream as a result of certain water resource management actions. These become increasingly likely since present structural approaches such as catchment storage infrastructure in the Incomati by way of the Maguga & Driekoppies dams will see the water allocation demands outstrip available supply through the three riparian states (e.g. Nkomo & van der Zaag, 2004). It is within this context that the project, Risk-Based Operational Water Management (RISKOMAN) is working with the water resource management authorities in the Incomati basin through action-research8 to develop state-of-the-art hydrological management tools. The aim being to alleviate the ‘risk’ in water allocation by developing non-structural approaches deployed via an integrated decision-support framework that can be used to manage the water resource within the bounds of hydro-climatic variability in this geo-politically sensitive closing river basin. A pertinent aspect of these objectives is to empower strategic governance in a fully informed collaborative manner where the stakeholders are able to negotiate the complexities of the diverse biophysical and multi-lateral problems in an international river basin such as the Incomati. Such an approach to seek consensual management has been highlighted by Turton & Ashton (2008) as key to the sharing of southern Africa’s water resources. Moreover, the notion of a shared vision for the status-quo of a catchment forms the central core of South Africa’s catchment management strategies (e.g. Pollard & du Toit) and one that is inclusive of transboundary obligations (e.g. ICMA, 2010). Slinger et al (2010) pointed to the fact that there is lack of a shared information resource in the Incomati basin, which means that each of the riparian states has differing perspectives on the status of the basin and this is a key factor that needs to be overcome.
This paper is a discussion of the RISKOMAN concept and the detail of the methodologies that will facilitate our approach.
8
Action Research - is a reflective process of progressive problem solving led by individuals working with others in teams or as part of a "community of practice" to improve the way they address issues and solve problems
2.
Methods
2.1
General Approach
The crux of the RISKOMAN approach is to generate improved understanding of the natural processes within the Incomati catchment in order to derive management actions around the variability in its hydrological fluxes at various spatio-temporal scales. This is in such a way that the water resource manager and their governors become more familiar with the emergent physical properties of the catchment and knowledge of their uncertainties, as advocated by Ferrier & Jenkins (2010) & Wagener et al (2010), see for instance Figure 2. To this end, RISKOMAN, is working in close collaboration with the ICMA in particular who use the framework of Strategic Adaptive Management (SAM) as their modus operandi. The cornerstone of SAM is to generate management decisions that take cognizance of a systems variability, and that are reached through consensus which is strategic, adaptive to change and also creative, so that a there is a partnership in the management of the resource that is inclusive of both science and society (Rogers et al, 2000).
Figure 2.
Emergent catchment hydrological processes and the scales of uncertainty in their determination (Source: Ferrier & Jenkins, 2010).
Moreover, SAM is a framework for dealing with complex problems in natural resource management emerging from resilience and ecosystem thinking and may be applied in multi-scale nested approach when managing the flows within a catchment (Kingsford et al, 2011). In this context the narrative in modern SAM literature is to find simple solutions to negotiate conceptually complex problems, such as the requisite simplicities, that is, information which has the minimal detail required in which to make an informed decision without getting suffocated by the complexity of the detail (Stirzaker et al, 2010). This is pertinent given that water resource managers in the ICMA report to a governing board, and international partners report to the TPTC 9 when managing for the Interim Inco-Maputo Agreement (IIMA). The role of the board is to steer the direction of ICMA (or TPTC to steer the IIMA) in meeting the requirements of all the stakeholders within the catchment that they represent, to achieve their vision for the status of the catchment (ICMA, 2010). The point being that it is necessary to enhance the technical capacity, whilst minimising training time and finance costs, of these representatives who are themselves drawn from a variety of external sectors whose first-hand experience is not water resource management or hydrology per se. Because of the inherent complexities in catchment management the advocated approach is one of finding methods or tools that assist in this cyclical social-learning in order to be informed, reflect and adapt to uncertainties, so that rather than trying to develop models for achieving an end-point in water resource optimisation, stakeholders and managers can actually already be in dynamic phase of change with the aim of achieving the the catchment vision (Pahl-Wostl, 2007).
9
TPTC – Tripartite Permanent Technical Committee
In reconciling the needs of the decision-maker and acknowledging that there are uncertainties inherent in the estimates of water resource status in a complex and dynamic system, it is also worth noting the concept of irreducible uncertainties (Stirzaker et al, 2011). This is a reductionist approach to identify parameters required for complex decision making that are known or quantifiable from those that are unknown, to effectually reduce the uncertainty around an estimate, on which one would justify a decision. Hitherto, hydrology and water resource management models often relied on estimates, which in themselves are constrained by uncertainty of model inputs and parameter development (see for e.g. Beven, 2007). This of course leads one to question: the accuracy of data?, and in the Incomati there would also appear to be some data incompatibility between the three basin states, and further hampered by data-scarce regions of the basin and degraded infrastructure and data (e.g. Slinger et al, 2010). However progress in science and technology in these fields have reduced the uncertainties in the way estimates have been made over time. The relevance of this statement is that present well tested techniques allow one to quantify hydrological fluxes across a landscape at both high spatial and temporal resolution, to the point that they are now ready to be tested in real-time decision-making applications. RISKOMAN uses this justification to test new techniques in hydrological remote sensing (RS) and hydrochemical analysis in the water resource decision-making field, at both the operational and governing levels for short, medium and long term10 water allocation in the Incomati.
Furthermore, it is hoped that these tools will assist planners within and external to the water resource management debates to examine land-use in longer term strategic planning across the whole Incomati. Integrated Land and Water Resource Management, ILWRM (Calder, 2005) is the proposed initiative to achieve such holistic sustainability. From the hydrological perspective, the explicit determinations of blue (runoff, recharge) and green (productive use: transpiration and evaporation) water flows are key to achieving this and have been described at length by Falkenmark & Rockström (2004). It has been highlighted as critical by Jewitt (2006) that the temporal scale at which green water is quantified needs to be accounted for in water resource allocations. This is because changes in green water flows as a result of changes in land use may have many different temporal trajectories in their response to the alleviation of water from productive uses to emerge apparent at different parts of the hydrological cycle, i.e. there are different rates of conversion of flow to runoff to that of baseflow, for instance.
2.2
Key Concepts
Given the catchment management context described, there are certain hydrological concepts relevant to the RISKOMAN approach. Following earlier discussion it is possible to adapt Molle et al’s (2010) model of catchment closure by incorporating blue-green water flows into the efficiency-in-allocation problem, as revealed in Figure 3. Here one notes the general transition of a closing basin after socio-economic and agrarian developments in a catchment deplete the available resource down to non-negotiable/committed levels such as international flow requirements and the reserve (ecological and basic human needs). Here we add a variable zone between the committed flows and the maximum residual outflow where both structural and non-structural responses can be utilised to mitigate against future uncertainties and improve efficiency in the use of the resource, in order to hedge against possible future losses.
However, all this of course requires a sound understanding of the systems hydrological regime, i.e. the processes that drive its natural variability, hence Figure 4 which provides an example of a rivers flow regime as a percent of time, in a flow duration curve (FDC). In this example we see a river, such as the Incomati with a strongly seasonal flow regime, dominated by high flows for a short period of time during a single rainy season, thereafter becoming largely low flows as the catchment storage is depleted from the soil and low yielding aquifers but, where potential evapotranspiration remains fairly high. In other catchments the flow could be more sustained, and this could be related to a combination of factors such as a longer rain season, with low evapotranspiration, high yielding aquifers and good soil moisture storage for example, but also due to the anthropogenic changes in land-use, such as a conversion of agro-forestry to annual crops and increasing storage through the building of dams. 10
Which we here define as short: days to weeks; medium: weeks to months; long: months to years
In relating the use of blue-green water flow determination for managing catchment scale efficiency, Figure 5 gives the conceptual approach. In this hypothetical example blue and green water flows are expressed as a proportion of total catchment outflow in a FDC. This follows the typical hot wet summers that characterise the Incomati basin, whereupon there is high runoff generation and actual evapotranspiration close to potential rates, since water in the landscape will be less limiting than in the dry winters, where low flows dominate. This would be the natural scenario at least. However since there are two extensive agrarian land-uses in the catchment, forestry in the headwaters and sugarcane cultivation in the middle and lower reaches in South Africa-Swaziland and Mozambique respectfully. This has two effects: firstly plantation forestry is known to be largely unrestricted by water deficit and is suspected to tap deeper soil moisture stores (Dye & Versfeld, 2007); Second, sugarcane a water thirsty ratoon crop requiring constant irrigation and at least in the Crocodile sub-basin it is grown perennially (DWAF, 2009). The compound effect of this is therefore the anti-seasonal transformation of blue- to green- water flow through evapotranspiration, the enhanced green water and depleted blue water flow in Figure 5. There is also an inherent paradox in the case of sugarcane and other irrigated crops in that under drought conditions, the catchment soil moisture deficit increases and atmospheric demands increase (humidity drops) thereby increasing the effective demand for irrigated water, despite a depletion in it’s natural availability.
Figure 3.
Typical scenario of river basin closure (adapted from Molle et al, 2010): developments deplete total basin runoff from the natural condition (1); the remaining flow after depletion which can be anywhere between 0 and total flow (2); and the zone where efficient-adaptive allocations can be made (3).
Figure 4.
Variability in a rivers flow regime expressed as a flow duration curve, FDC (*land-use changes and infrastructure developments such as dams may cause an artificial shift in the FDC).
Figure 5. A hypothetical FDC revealing the partition of the total flow (Q) into blue and green water components, in a semi-arid basin such as the Inkomati where low flows dominate for a significant proportion of the time, but agricultural production continues there is a significant conversion of blue water to green water (NB. the ecological reserve will include both blue and green water).
It is these concepts that then need to be retrofitted to the SAM frameworks already in place for short-, mediumand long- term planning in the interests of ILWRM. Moreover, in order for this to be inclusive and representative of all stakeholder interests the aim is to not limit this to hydrology per se but rather all other aspects of the water allocation problem, particularly economic strategy for the basin. The specific aim being to developed net economic benefit functions available to water managers and governors that are derived from specific uses of basin water resources. Such as the residual imputation, avoided cost, econometric estimation of
consumer demand are the primary methods employed for valuing water use in agriculture, energy production and municipal use respectively (Young, 2005; Ward and Michelsen, 2002). In this respect the notions of water productivity (WP), i.e. the unit crop produced per unit water and/or the water footprint i.e. the unitary impact on the ecosystem goods and service values of water, in essence place an economic value on green and blue water flows respectively. Modern thinking on water policy integrates these factors to now take the view of basin scale water productivity, for holistic water accounting, whilst new technologies in remote sensing and hydrological modelling are advocated for this approach (e.g. Cai et al, 2011).
To this end, RISKOMAN has the following objectives that it will address in close collaboration with the ICMA, KOBWA and other organisations in the Incomati: 1) Better understanding of the hydrology and water use of the Incomati Basin 2) Explore the possibilities that would result from a more reliable forecasting system 3) How to develop a more optimal seasonal water allocation policy based on existing allocation and how to optimise existing allocations 4) Investigate the economic gains and losses achieved through transfers 5) Develop policy instruments for exchanging compensation between water users. 6) Develop an interactive multilevel stakeholder information system with emphasis on targeting the CMA board members. 7) Improve the understanding of the catchment through the use of remote sensing and earth observation (EO) using the most advanced techniques and delivering the data in a form that it is applicable for several different models already being used in the Incomati Basin.
2.3
Tools
In order to reconcile the objectives of RISKOMAN into a coherent initiative, a basin level information utility will be developed that facilitates the institutional capacity for informed decision-making within the Inkomati CMA and hopefully other transboundary partners in all three riparian states. Moreover, this will be geared to empowering the ICMA’s governing board, in the first instance, through information bridging between themselves and their managing executive (see Figure 6), in the interest of strategic and adaptive governance. It must be stressed that this does not seek to create a new decision-support system (DSS) within the ICMA and the broader Incomati but rather fill a potential gap and at the same time become integrated with real-time DSS’s already in place at the behest of the water managers (Riddell & Jewitt, 2010).
To this end, it is imperative that the requirements of the end-user are considered at every stage of the information utility’s development, as such the project will facilitate a social-learning environment through oneon-one interviews and interactive workshops with the ICMA’s governing board members and managers whilst concurrently fostering a similar information exchange with KOBWA and the PRIMA initiative through the various regular joint11 operations forums in the basin. These will cover the topics and feasibility of integration to
11
The ICMA, KOBWA, PRIMA and Sabie-Sand Real Time Project (DWA) have regular joint meetings including representatives from the three riparian states discussing systems operations (short-medium term) and longer term water resources planning.
a programmed utility, whether it be a website, interactive computer model, or other such innovation, to include the following key factors:
- validity of hydro-climatic forecasts; - spatio-temporal hydrology and processes; - early warning systems, hydro-economic forecasts and trade-off scenarios; - water accounting (blue and green; micro and macro scale); - ecological reserve and international flow requirements; - adaptive management; - land-use management scenarios; - other social learning criteria; - system utility and interface.
Figure 6.
Schematic of the development and placement of RISKOMAN tools within the Incomati (The ICMA is depicted here as the principal beneficiary, however it is foreseen that this will foster information bridging to other institutional partners in the basin, such as KOBWA and PRIMA Initiative).
The use of new hydrological technologies in RISKOMAN to achieve these objectives will now be outlined. The first relates to the often illusive factor in hydrological modelling, the evapotranspiration (ET) flux, which has
traditionally relied on meteorological based estimates to develop potential (pET) demands. Actual ET, or aET can now be determined from various RS techniques to measure the surface energy balance at the earths surface. With specific reference to the entire Incomati is the Surface Energy Balance Algorithm for Land, SEBAL (Bastiaansen et al, 2005) which is presently being tested via a concurrent partner project, ‘Spatial earth observation monitoring for planning and water allocation in the international Incomati Basin’ (WATPLAN) by WaterWatch BV, The Netherlands. The SEBAL method uses remotely sensed images of visible, near-infrared and thermal infrared radiation to derive the net radiation, sensible heat flux, and soil heat flux, which through energy balance equations derives residual evapotranspiration estimates on a pixel-by-pixel basis (Trezza, 2006). Kongo et al (2010) recently applied SEBAL in the headwaters of the Thukela basin and revealed that reliable estimates of aET could be determined from SEBAL using ground-based calibrations from scintillometers and measured meteorological parameters. Where, monthly water uses could be differentiated based on land use types, and furthermore that reasonable monthly values could be determined from as few as 3-4 satellite images per month. The key outcome of Kongo et al (2010)’s work was that they foresaw that these large spatial determinations of ET could be combined with hydrological and water resources planning models to in effect develop scenarios of alternative land-uses in terms of ‘hedging’ for water availability.
In rainfall-runoff, or hydrodynamic models soil moisture is often a key parameter used to partition rainfall into surface runoff and infiltrating water. Typically when used to inform a model it is derived through point measurements before being upscaled usually relying on a variety of estimates and assumptions. Modern RS methods now allow for the determination of spatially averaged soil moisture. These techniques have been assessed for some South African conditions by Vischel et al (2008). They assessed the performance of two methods related to satellite derived scatterometer data which are sensitive to the moisture content of near surface soils. Through the correlation of this RS data with modelled calibrated soil moisture data, they found good agreement and foresaw the development of spatially averaged soil moisture data that could also provide some vertical resolution to the data critical for hydrological modelling.
RS rainfall estimates have gained significant ground in recent years and are already proving valuable in hydrological modelling systems, for instance they are already used in a number of real-time modelling systems in the Inkomati WMA, such as the Crocodile Real-Time DSS in Mike Floodwatch (DWA, 2009). Sawunyama and Hughes (2008) highlighted the value of this new source of data but recommended correction algorithms for this data against historical rainfall data sets from terrestrial rain gauges but also identified the need to spacially correct this satellite data for orographic effects.
Van Dijk and Renzullo (2011) provide a thorough review of similar EO technologies, when applied to water resource monitoring systems in Australia. They conclude that utility of such observations vary according to the dominant hydrological processes in a basin, since the accuracy of satellite quantification of various fluxes still varies considerably between parameters such as soil moisture, ET and groundwater levels. Nevertheless, the utility of such products for dynamic forcing, or upscaling/interpolation of observed ground based measures is critical, since in the absence of large scale measurements provided via EO technologies, the traditional bottomup approach for scaling point measurements to the larger scale is fraught with uncertainties, arising from multidimensional heterogeneities and non-linear processes.
It is to this end that RISKOMAN will clarify the dominant stream-flow generation processes in the basin, as a benchmark. This will be achieved through comprehensive spatio-temporally fingerprinting of the Incomati’s hydrological regime, in order to identify sources, pathways and response times of components of discharge in a nested multi-scale approach from the headwaters to the estuary. Through repeated snap-shot (Grayson, et al 1997) water sampling procedures at every confluence and discharge point at an instant in time, the analysis will yield a geographical overview of stream hydrochemistry and isotopes species in relation to watershed geology and land-uses. This has the benefits of providing for differentiation of near-surface ‘quick’ flows from intermediate low flows and groundwater maintained base flows in the system. This has important ramifications for understanding the impacts of managing the various temporal sources of water in the basin and establishment of background loads of some hydro chemicals (nutrients, isotopes) giving basis for evaluating the influence of non-point sources and return flows from agricultural areas. The suggestion that this level of hydrochemical
detail from stable river regimes leads to better management decisions has been posed by Salvia et al (1999) and Wayland (2003). 2.4
Integration
The hydrological aspects previously described would then need to be integrated in such a way that makes data output relevant to the non-structural water allocation problem. This will be achieved by using economic factors as the key dependent variables in an optimisation approach. Such a hydro-economic model would aim to maximise the international basin-wide benefits for the medium to long term via scenarios analysis. These scenarios would be achieved through the use of an optimatization algorithm designed to handle large numbers of alternatives and constraints, and would identify inter-regional and inter-sectoral allocations and pricing from hypothetical water markets in the three countries of the Incomati. Details of such an existing hydro-economic modelling platforms have been described by Tilmant and Kelman (2007). Tested models of this type have included coupling surface-groundwater allocations to various sectors via a hydro-economic model in India (George et al, 2011). Moreover it is anticipated that this could be multi-scaled by incorporating actual quantitatively derived micro-scale hydro-economic indices resulting from the new aforementioned RS techniques. A valid product to achieve this has been demonstrated by Hellegers et al (2009) in the lower Komati sub-basin to link various crop water productivities at the farm level against the actual volumes of water used (rather than allocated) derived via SEBAL. 3
Discussion: Expected Results
It is anticipated that our conceptual approach outlined in this manuscript will form the basis on which to develop a catchment information utility that is both transparent and comprehensive in the way that information is disseminated and furthermore that ultimately it allows for adaptive decision making to facilitate strategic water resource governance in the heavily committed Incomati river basin. However we acknowledge that through the social learning approach we are undertaking that these concepts will themselves be continually refined as the project proceeds.
To this end RISKOMAN will empower the stakeholders in each of the riparian states of the Incomati to appreciate the various trade-offs that are incurred as a result of a specific water allocation scenario, and this is why it is important to take a nested but basin wide approach so that all these aspects can be considered at a variety of spatial and temporal scales. This is in order to foster holistic systems thinking, and develop appreciation for marginal water values both within national boundaries and across the transnational divides when planning to hedge the use of the resource (the green water zone). This presupposes a sounds understanding of the hydrological template of the Incomati and this will be a product in itself of RISKOMAN, furthermore it will augment the complex interlinkages of the biophysical with the socio-economic and socio-political setting of the basin so that one sector may observe how and why a temporary or permanent reallocation of water has a certain hydrological, or economic effect on another sector (or user) in the catchment.
It is anticipated that this research will result in a utility that is applied and that has transferability to other heavily committed basins in the southern African region and elsewhere. Whilst of course it is acknowledged that the uniqueness of place and circumstance will result in such catchment information utilities varying in their final scope and design, it is anticipated that there will nevertheless be particular core operabilities in its end-use emanating from the framework that will be set-up in RISKOMAN.
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