Challenges Facing Environmentally Sustainable Ground Water Use in South Africa

Issue Paper/

Challenges Facing Environmentally SustainableGround Water Use in South Africaby Paul Seward

AbstractIn 1998, South Africa promulgated a Water Act that is widely regarded as one of the most progressive and

enabling pieces of environmental legislation in the world. The environmental aspects of the Water Act are com-monly referred to as ‘‘resource-directed measures.’’ These measures attempt to find the right balance between (1)leaving water in the resource (‘‘nonconsumptive use’’) to provide ecological goods and services for society and(2) taking the water out of the system for ‘‘consumptive’’ human use. These measures also attempt to ensure thatboth nonconsumptive and consumptive use is sustainable. This article discusses some of the challenges faced inusing the measures to achieve environmentally sustainable ground water use. A major challenge is that misunder-standing still abounds regarding the environmental aims of this legislation. Other major challenges identifiedincluded a severe shortage of technical capacity, an inordinately long water use license application process, incor-porating adaptive management to deal with uncertainty, incorporating the public participation process, and revis-ing policy implementation processes to accommodate highly localized aquifers. Selecting appropriate scientificmethodology—neither too simplistic nor too involved—is a recurring challenge. It is suggested that an importantpart of addressing these and the other challenges identified is a period of reflection and dialogue between the vari-ous sectors involved.

IntroductionHistorically, the function of South Africa’s Depart-

ment of Water Affairs and Forestry (DWAF) was to meetthe needs of those water users that the government choseto assist (DWAF 1997). A large proportion of that assis-tance went to enable white farmers to irrigate their crops.Concern for the environment was not paramount. This haschanged in democratic South Africa, with DWAF nowresponsible for ensuring all its citizens have access to safewater and also for ensuring an optimal balance betweenconsumptive water use and water conservation via a newWater Act (Republic of South Africa [RSA] 1998) that iswidely regarded as one of the most progressive and

enabling pieces of environmental legislation in the world(Postel and Richter 2003). But progressive new legisla-tion does not necessarily bring about positive results, evenwith a massive commitment to change (Van Wyk et al.2006).

Implementing the policies associated with the newlegislation is like ‘‘climbing an uncharted mountain’’(MacKay et al. 2003) and must be done in small steps.Making mistakes is an unavoidable and essential part ofthe learning process. Periodically taking time to reflectand to review the progress so far and what the next stepshould be is a crucial but undervalued and neglected partof the ‘‘mountain-climbing’’ process. This article reflectson the challenges facing the implementation of the poli-cies to ensure environmental sustainability in the groundwater field.

The environmental concerns of the National WaterAct (RSA 1998) are commonly referred to as ‘‘resource-directed measures’’ (RDM), although this term is notactually used in the Water Act. The RDM term refers toa set of policies in the White Paper (DWAF 1997) that

Department of Water Affairs and Forestry, Bellville, South Af-rica 7530; 27 21 9507268; fax: 27 21 9507150; [email protected]

Received May 2007, accepted September 2008.Copyright ª 2008 The Author(s)Journal compilationª2008NationalGroundWater Association.doi: 10.1111/j.1745-6584.2008.00518.x

NGWA.org Vol. 48, No. 2–GROUND WATER–March-April 2010 (pages 239–245) 239

were subsequently included in the Water Act as part ofthe ‘‘Protection of Water Resources’’ chapter. The basicaim of RDM is to set clear objectives for the desired levelof protection for each resource, including the optimal bal-ance between ‘‘consumptive use’’ (taking water out of thesystem) and ‘‘nonconsumptive use’’ (conservation, leav-ing water in the system). These objectives then becomelegally binding and must be taken into account when anyother aspect of the Water Act is being implemented (e.g.,issuing a water allocation license that authorizes the useof ground water).

‘‘Consumptive’’ use means things like water forhousehold purposes, irrigation, and industry. ‘‘Noncon-sumptive use’’ includes the ‘‘silent’’ goods and services(MacKay and Moloi 2003) that are part of a much broaderplanetary ‘‘life-support system’’ and includes functionssuch as:

d Assimilation, decomposition, and transport of biodegrad-

able wastes.d Sequestration of heavy metals.d Attenuation of floods and mitigation of potential flood

damage.d Storage of water for later release in the dry season.d Food resources such as fish, shellfish, and plants.d Material resources such as reeds and timber.d Medicinal plants.d Support of subsistence livelihoods such as floodplain

agriculture.d Maintenance of cultural, spiritual, and recreational activi-

ties, for example, ecotourism.

Overall Philosophy of RDMBy standing back and taking a broad view of RDM

policy, legislation, and attempts at implementation, itwould appear that two key underlying concepts can beunraveled. One is the concept of ‘‘optimization,’’ imply-ing that there is an optimal range (McCartney et al. 2000)for the combined benefits of taking a certain amount ofwater out of a system and leaving water in the system forresource and ecosystem integrity (Figure 1). Initially, netbenefits rise as consumptive use increases until an opti-mal level is reached, whereafter net benefits begin todecrease as more water is taken out of the system.

The second key concept involved in RDM is that ofa ‘‘threshold’’—if the consumptive use of water continuesto be increased, it will eventually pass a point whereby theintegrity of the resource and/or key ecosystems dependenton the resource are threatened. The sustainability thresholdis shown as a band rather than a line on Figure 1 toemphasize that it is not a precise line that scientists canreadily determine or that society can readily agree on.

Besides these key concepts, there is the key processof public participation. The threshold and the optimal userange cannot be decided on by science alone but needa public participation process so that the public’s valuescan be taken into account.

Overview of RDM Implementation ProcessThe three key components of RDM in the National

Water Act (RSA 1998) are as follows:

1. Classification—determining a class for all or part of every

significant water resource that specifies the level of pro-

tection that is required.

2. The ‘‘Reserve’’—the Reserve has two components: (1) the

quantity and quality of water required to satisfy basic

human needs and (2) the quantity and quality of water

required to protect aquatic ecosystems in order to secure

ecologically sustainable development and use of the rele-

vant water resource

3. Resource quality objectives (RQOs)—the aim of RQOs

is to assign tangible, monitorable parameters for the re-

source, based on Classification and the Reserve, that rep-

resent the desired state of the resource for all the

stakeholders concerned. Resource quality means the qual-

ity of all aspects of a water resource and not just water

quality. It therefore includes the quantity of water in the

resource, riparian habitats, and aquatic biota.

Ground water ecosystems per se are largely ignoredby the RDM process, and ground water is basically re-garded as just an underground reservoir that supplieswater either to people or to surface ecosystems. It is spec-ulated that this neglect of ground water ecosystems isbased on the assumption that they provide little in theway of goods as services. This assumption may or not becorrect. What is clear, though, is that research into under-ground ecosystems has lagged behind surface water eco-systems and much more research is needed (Hancocket al. 2005).

ClassificationA generic approach for classifying all water resour-

ces was proposed by DWAF (1999a), which revolved

Figure 1. Benefits of water use vs. percentage of consump-tive use (adapted fromMcCartney et al. 2000).

Percentage consumptive use 100%0%

Ben

efits

Sustainabilitythreshold

SUSTAINABLE UNSUSTAINABLE

Optimal Total benefits

Consumptive benefits

Nonconsumptive benefits

240 P. Seward GROUND WATER 48, no. 2: 239–245 NGWA.org

around determining (1) actual conditions; (2) desiredconditions; and (3) an appropriate management class(Table 1). The management class attempts to integrate therules for protection of ecosystems, basic human needs,and consumptive water use.

Ground water classification followed the same gene-ric approach (Parsons and Wentzel 2005), and the presentstatus of ground water resources was classified accord-ing to (1) how impacted they were by ground waterabstraction; (2) ground water contamination; (3) land use;(4) environmental impacts; and (5) a ‘‘stress index’’(Table 2).

The overall present status category is determined bytaking the worst of the individual status categories. Prog-ress with the classification of ground water resources hasthus far been mainly in the form of generating guidelines,frameworks, and manuals.

The author suggests that the classification of groundwater resources into three management classes has littleinherent meaning or value in the ground water field,chiefly because the management of a ground watersystem revolves around dealing with a number of local-scale, often very site-specific issues. For example, stake-holders might insist that one major spring must remain inpristine condition and its historical flows maintained,while being amenable to another spring having seriouslydiminished flows. The ‘‘average’’ of this is an ‘‘average’’classification, which in no way reflects how stakeholderswant their resource to be managed. Adapting the classifi-cation process to accommodate highly localized and dis-continuous aquifers is an important challenge.

The ReserveThe Reserve has two components—protecting basic

human needs and protecting aquatic ecosystems so thatthey can be used sustainably. The quantity required forbasic human needs (officially defined as 25 L/d/person)is usually miniscule compared with the water available ina given ground water resource and is therefore not usu-ally an issue. Protecting water quality for basic humanneeds is usually more important. The ‘‘ground water eco-logical Reserve’’ is actually the amount and quality ofground water that must be maintained in order to protectsurface ecosystems.

The basic procedure used for determining the groundwater reserve (DWAF 1999b) is to estimate averageannual recharge, subtract what is needed for basic humanneeds, subtract what is needed for low maintenance baseflows, and allocate the rest for consumptive use. Sewardet al. (2006) have shown that this approach is conceptu-ally flawed because (1) average annual recharge does notdetermine sustainability and (2) base flows can beimpacted way before abstraction has reached rechargeminus base flow volumes. The capture principle (Lohman1972; Alley et al. 1999) was put forward as a more practi-cal, and scientifically sound, basis for assessing groundwater sustainability and should therefore be employed inRDM determinations in place of annual average recharge.The capture principle basically states (Lohman 1972) thatthe long-term sustainability of ground water resources isdetermined by how much discharge can be captured and/or by how much recharge can be increased (Figure 2).

In our more environmentally aware times, theamount of capture that is acceptable, as well as possible,has to be determined. For example, it may well be possi-ble to use a ground water resource sustainably by captur-ing certain spring flows, but is this acceptable?

Table 1Generic Approach to Classification

Present Status Category Desired Status Category Management Class

A—effectively unmodified A—effectively unmodified I—‘‘Special’’—ecological constraints overrideB—mostly natural conditions B—mostly natural conditions II—‘‘General’’—a balance is sought between use

and protectionC—moderately modified C—moderately modifiedD—largely modified D—largely modified III—‘‘Hard working’’—socioeconomic factors overrideE—seriously modified (unsustainable and unacceptable)F—critically modified

Table 2Classification via a Ground Water Stress Index

PresentStatusCategory Description

Stress Index(abstraction/recharge)

A Unstressed or low levelsof stress

,0.05B 0.05–0.20C Moderate levels

of stress0.20–0.40

D 0.40–0.65E Stressed 0.65–0.95F Critically stressed .0.95

Figure 2. Water budget showing changes brought about byabstraction (Alley et al. 1999).

Pumpage

Decrease indischarge

Increase inrecharge

Removal of stored water

NGWA.org P. Seward GROUND WATER 48, no. 2: 239–245 241

Using the capture approach, although scientificallysound and realizing the aims of RDM, is likely to bemore involved than simply allocating a percentage of aver-age annual recharge. A flawed, but simple, process maybe more practical.

Progress with implementing the Reserve has pro-gressed further than Classification and setting RQOsbecause the Reserve must be set before a license to useground water can be issued. Not all ground water useneeds to be licensed. Domestic use, stock watering,small industrial use less than 20 m3/d, water use ‘‘gener-ally authorized,’’ and use in place before the 1998 WaterAct do not require licensing. The licensing process islengthy, often taking 2 years or more to complete, andis often regarded as a tedious piece of bureaucracy ratherthan as a powerful tool for ensuring sustainability, espe-cially when license applicants usually expect the processto be completed in a few months. The lengthy im-plementation process weakens the effectiveness of thelegislation.

Experience suggests that local concerns and experi-ence are often of more practical value than the Reservenumber when a license application is being considered.For example, at Jan Dissels River, near Clanwilliam,some 230 km north of Cape Town, the community wasfar more concerned about the potential impacts of groundwater abstraction on streamflows (Seward et al. 2006)than the percentage of annual average recharge that theReserve was set at. In this case, the concerns were codi-fied into the licensing process by the setting of appropri-ate monitoring conditions. In general, though, findingways to codify local experience, issues, and expertise intoground water management is a major challenge.

Another problem with the implementation of theReserve is the popular use of the ‘‘bucket analogy’’(Figure 3). This analogy is used to show how groundwater is shared out, principally from a legal perspective.It creates the false impression, however, that everythingthat is left over once water is allocated for the ecological

and basic human need Reserves can be allocated for‘‘consumptive use’’ without impacting the Reserve.

If the bucket analogy is made more physically real,and transformed into a (very) hypothetical aquifer system(Figure 4), the problems with this analogy become clear.The water needed by ecosystems is sitting at the top ofthe aquifer system. Therefore any ground water use couldimpact ecosystems.

The challenge here is to find the right balancebetween simple concepts that are easily communicatedand concepts that are theoretically sound but not alwayseasy to grasp. In the case of the bucket analogy, theproblem appears to have come from taking a simpleresource allocation concept and extending this analogyinto fields that were never intended—a cross section ofan aquifer.

The Reserve is not something that can realistically orusefully be pinned down with firm numbers for quantityand quality of water but rather a threshold that needs tobe negotiated. The National Water Act (RSA 1998) speci-fies that the threshold only applies to basic human needsand aquatic ecosystems. It is suggested that the Reserveconcept would be a better management tool if it hada much broader application and marked the threshold thatshould not be crossed regarding all unsustainable impactsand not just unsustainable impacts on surface aquatic eco-systems or basic human needs. For example, in karstic en-vironments, the Reserve might well be set so as to preventsinkhole formation.

In other words, the Reserve should specify thethreshold between acceptable and unacceptable manage-ment classes, between sustainability and unsustainability—a threshold that must not be crossed if resource andecosystem integrity are to be attained. This was the origi-nal intention of the Reserve as presented in the WhitePaper (DWAF 1997)—‘‘The objectives for each aspect ofthe Reserve will show what degree of change is consid-ered acceptable, and unlikely to damage a water resourcebeyond permanent repair.’’ This broad intention was omit-ted from the National Water Act (RSA 1998).

Figure 3. Allocating water from the ground water ‘‘bucket.’’ Figure 4. Effects of abstraction on the ecological Reserve.

Basic HumanNeeds Reserve

Allocatableportion forconsumptiveuse

Physicallyunabstractable

EcologicalReserve


Resource Quality ObjectivesThe intention of RQOs is to translate the aims of

Classification and the Reserve into parameters that canbe monitored and can be used to guide the water alloca-tion process. The National Water Act (RSA 1998) allowsRQOs to apply to basically any characteristic.

Xu et al. (2003) see this as particularly importantsince it allows for the full ecosystem functioning ofground water to be recognized and protected where nec-essary. For example, the Reserve only deals with theprotection of aquatic ecosystems, while terrestrial ecosys-tems would need to be protected by RQOs. The powerand flexibility of RQOs must, however, be tempered withwisdom, so that the objectives set are actually of use. Theobjectives must have scientific meaning with respect tosustainability, be readily understood and accepted as use-ful by all the participants in the management of theresource, and be monitorable.

Preliminary attempts at selecting suitable RQOs(DWAF 1999b) looked at maintaining regional water lev-els, maintaining ambient ground water quality, and ensur-ing that ground water use may not impact river and springflow, riparian or terrestrial vegetation, or land stability.However, progress with the practical implementation ofground water RQOs has been very limited.

Misunderstandings about RDMOne of the problems with implementing RDM is the

diverse opinion as to what they actually mean. Van Wyket al. (2006) note that many people incorrectly view thesemeasures as pitting people against the environment. Thisthinking sees nature and people with no interdependentneeds and has contributed to people undervaluing theRDM approach. Van Wyk et al. (2006) suggest thatone solution would be to regard everything that is pro-vided by a water resource, whether consumptive use ornonconsumptive use, as goods or services that benefit dif-ferent people at different distances from the resource. Atown’s drinking water, ecotourism, growing crops by irri-gation, and storage of water for future use are all goodsand services that ground water systems can directly orindirectly provide.

It is suggested that scientists and water resourcemanagers themselves have contributed to society’s con-fused and negative attitude to RDM by forever oversim-plifying the purpose of the ecological Reserve to ‘‘protectaquatic ecosystems.’’ The Water Act (RSA 1998) in factstates that the purpose of the ecological Reserve is to pre-serve its sustainable USE—that is, for the benefit ofhuman beings, rather than preserve its natural state.

Public ParticipationPublic participation is an essential part of the RDM

process but has hardly been featured in ground waterRDM so far, mainly because the process has simply not

yet reached the stage where public participation isrequired. Pienaar (2005) points out that a clearer pictureis needed on how to proceed from Classification and theReserve to RQOs via a process of public participationand calls for research to be done to formulate a morestructured approach to public participation. Research into,and practical testing of, various structured adaptive man-agement approaches would appear to be a fruitful area ofresearch in making RDM work.

Nonwater Act Management StructuresThe ability of local and seemingly ‘‘toothless’’ man-

agement structures to reserve and allocate water viaa structured process, yet without making use of any ofthe legal tools provided by the National Water Act, isoften overlooked. For example, a 10% reduction in yieldof a significant intergranular aquifer at Langebaan Road,some 100 km north of Cape Town, was brought about bya monitoring committee, without resorting to the toolsavailable in the National Water Act simply because thecommittee (representing many diverse and conflictinggroups) managed to agree that the resource was beingoverutilized and wanted to see if a 10% reduction wouldhelp. Optimally using these ‘‘voluntary’’ managementstructures is an important challenge for the implementersof RDM.

Priorities—RDM Are Not Needed EverywhereFor large parts of South Africa, ground water yields

are so low, and aquifers so localized and discontinuous,that no regional impacts are caused by local overabstrac-tion, and the only person negatively impacted by over-pumping is the person doing the pumping, whoseborehole may dry up. In effect, these low-yielding resour-ces ‘‘manage themselves’’ by putting a practical and eco-nomic limit on what can be abstracted from them. It issuggested that in such circumstances, any form of RDMis overkill, a waste of scarce resources, and should not beimplemented. This would imply authorizing water usewithout licenses since licenses require the Reserve bedetermined. In practice, this would mean major down-scaling of the geographical extent of the areas where li-censes are needed. The challenge here is to agree onwhich areas need RDM. The tendency is to protect thelow-yielding aquifers, when—as noted previously—theseare often ‘‘self-regulating,’’ and it is often the more pro-ductive aquifers than need the most protection fromoverabstraction.

Dealing with UncertaintySeward et al. (2006) have argued that many of the

numbers determined by ground water scientists can easilybe an order of magnitude out. Our knowledge of surfacehydrological parameters shows similar error margins.Quantitative knowledge of ecohydrology is even more


uncertain, making it difficult to make even educatedguesses as to the likely impacts of ground water use(Hunt and Wilcox 2003; Hancock et al. 2005).

Yet, despite all these uncertainties, water resourcemanagers are somehow expected to provide ways andmeans of fairly allocating ground water and ensuringthat its use is sustainable. The resolution of thisdilemma is an appropriate management approach todeal with these uncertainties, rather than perpetuatingthe illusion that—with sufficient funds—we will oneday be able to determine the relevant parameters accu-rately. Adaptive management or ‘‘learning by doing’’(Walters and Hollings 1990) was proposed by Sewardet al. (2006) as the most sensible approach to groundwater management. Adaptive management could simplybe described as iterative, but structured, hypothesis test-ing in a participative management environment. Such anapproach need not be at odds with the National Water Act(RSA 1998) since periodic reassessment and stakeholderparticipation are required.

It has become popular in ground water RDM to as-sign tags like ‘‘high confidence’’ and ‘‘low ‘‘confidence’’to numerical estimates of, for example, the Reserve, butit is rarely clear what high and low confidence actuallymean. High confidence might just mean that a lot of timeand money has been thrown at the problem and mighthave very little to do with the error margins in the finalestimate. To address this issue, hydrogeological studiesneed to incorporate more formal and meaningful descrip-tions of the accuracy of the numerical estimates provided.

The major implications for hydrogeologists in deal-ing with uncertainty using an adaptive managementapproach are (1) abandoning the notion that determiningground water sustainability can be determined exclusivelyby science and (2) abandoning the notion that groundwater sustainability can be expressed as precise numberor even a number at all. Instead, based on their under-standing of the ground water and related systems underscrutiny, hydrogeologists should be presenting to stake-holders alternative hypotheses on the impacts of groundwater use and ensuring that whatever hypothesis isselected is investigated in a scientific manner, forexample, by ensuring that appropriate monitoring isdone.

Technical CapacityThe previous discussions have assumed that the

South African Public Service has the technical capacityto implement the new legislation. This is far from thecase, with critical shortages in many occupations. There-fore, it is clear that strategies are needed to address theseproblems. These strategies might include steps to makeemployment in the public sector more attractive, steps tomake the legislation simpler to implement and thereforerequiring less technical capacity, and steps to ensure thatthe legislation is only used where there is an urgent needto do so.

ConclusionsA number of challenges facing the implementation

of environmentally sustainable ground water use in SouthAfrica have been outlined:

d Overcoming the misunderstandings about the aims of

RDM.d Finding strategies to deal with the severe shortage of tech-

nical capacity.d Finding ways to dramatically shorten the time needed to

process water use license applications.d Finding the right balance between using simple, easy-to-

use but scientifically flawed methods and scientifically

correct but complex and involved methods. This applies to

both the use of science and the way scientific concepts are

presented to stakeholders.d Revising the Classification process to accommodate the

highly localized and discontinuous nature of South African

aquifers.d Incorporating the public participation process.d Incorporating adaptive management.d Reviewing the methods used to determine the priority

areas where RDM are applied.d Effectively using voluntary management structures in the

statutory management process.d Codifying local knowledge into the water management

process.d Acquiring a better understanding of underground eco-

systems.d Assessing whether a much broader ground water Reserve

is needed that includes all aspects of aquifer and related

ecosystem integrity.

It is suggested that a common thread linking all thesechallenges is the need for improved communication—communication between RDM specialists; between gov-ernment, science, and society; and between South Africanand international experts. Such communication, plusa period of reflection and reappraisal, is needed so thatthe ‘‘climb up the mountain of policy implementation’’can proceed with renewed vigor.

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Challenges Facing Environmentally Sustainable Ground Water Use in South Africa