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Problems of large-scale groundwater development
Journal o f Hydrology, 43(1979) 439-443 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands
439
[2] PROBLEMS OF LARGE-SCALE GROUNDWATER DEVELOPMENT
S. MANDEL Center for Groundwater Research, Hebrew University, Jerusalem (Israel)
(Accepted for publication February 7, 1979)
ABSTRACT Mandel, S., 1979. Problems of large-scale groundwater development. In: W. Back and D.D. Stephenson (Guest-Editors), Contemporary Hydrogeology -- The George Burke Maxey Memorial Volume. J. Hydrol., 43: 439--443. The difficulties encountered in the planned development of groundwater resources are analysed by comparing typical "scripts" for surface and groundwater resources, respectively. The suggested remedies are: (a) campaigns of systematic field investigations in any area where the intensive exploitation of groundwater is envisaged; (b) standardization and codification of modern research techniques so that they can more readily be used by any investigator; (c) the construction of water supply networks serving more than one user in order to stimulate cooperation and mutual control among water users and to facilitate the centralized regulation of groundwater abstraction.
INTRODUCTION In 1 9 7 5 t h e late G.B. M a x e y and t h e a u t h o r w e r e engaged in studies o f g r o u n d w a t e r mining. A c o l l e c t i o n o f case histories revealed t h a t t h e overexp l o i t a t i o n o f g r o u n d w a t e r is a v e r y c o m m o n practice, especially, t h o u g h n o t exclusively, in d r y areas. G e n e r a l l y , w i t h v e r y few e x c e p t i o n s , o v e r e x p l o i t a t i o n d e v e l o p s u n i n t e n t i o n a l l y and is o n l y b e l a t e d l y recognized. Available d a t a r e f e r m a i n l y t o areas w h e r e a t t e m p t s are b e i n g m a d e t o r a t i o n a l i z e g r o u n d w a t e r m i n i n g a n d t o p l a n rescue schemes. D a t a f r o m areas w h e r e g r o u n d w a t e r m i n i n g " j u s t h a p p e n s " , o r w h e r e it has r u n its full d e s t r u c t i v e course, generally, r e m a i n inaccessible. T h u s t h e available d a t a are p r o b a b l y indicative o f a p r o b l e m t h a t will b e c o m e acute, o n a global scale, w i t h i n t h e n e x t t w o or t h r e e decades, unless t h e p r e s e n t t r e n d s in g r o u n d w a t e r d e v e l o p m e n t are reversed. T h e r e s p e c t i v e m e r i t s o f sustained yield e x p l o i t a t i o n versus m i n i n g m a y be arguable in each p a r t i c u l a r area. T h e w i d e - s p r e a d u n c o n t r o l l e d d e v e l o p m e n t o f irreplaceable w a t e r r e s o u r c e s is c e r t a i n l y an u n d e s i r a b l e state o f affairs. T h e p r e s e n t p a p e r a t t e m p t s t o analyse t h e reasons f o r this s i t u a t i o n and t o suggest r e m e d i e s against its f u r t h e r spread.
440 SCRIPTS FOR SURFACE WATER AND GROUNDWATER DEVELOPMENT The rational development of a natural resource requires information as input to planning, and planning as guide to action. However, the actual course of development tends to follow a "script" generated b y the interaction of human attitudes, technical, and societal factors. A comparison of typical scripts for surface water and groundwater development shows w h y it is relatively easy to follow rational procedures in the first case, while it is difficult to enforce them in the second one.
A typical script for surface water development (1) The drainage basin of the river is mapped and some quantitative data are collected long before large-scale diversions are thought of. (2) The design criteria of dams, spillways and intake structures are dictated by the stochastic hydrological characteristics of the river, not only by the discharges that are actually going to be diverted. As a consequence, larger works are able to supply water at a smaller unit cost, and the resultant "econo m y of scale" (Hall and Dracup, 1970) forces competitors for water supplies to cooperate already during the planning phase. (3) Legal doctrines recognize c o m m u n i t y rights on river water and refer to the watershed as basic natural unit. (4) Feasibility studies, based on a thorough investigation of the resource are mandatory because of the large investment that is involved. {5) The scope of investigations is widened in response to public concern with the environmental inpact of the project. (6) Quantitative investigations of the resource are based on flow gaugings and on meteorological observations, i.e. data that can be collected prior to any construction work. The long lead time between the study and the implementation of the project makes it possible to collect adequate data. (7) The completed scheme is operated by a statutory authority exercizing physical control over the installations. (8) Water users accept the necessity of regulation, since water abstraction by any one user visible affects water availability to all other users. (9) Even gross mismanagement is unlikely to damage the resource.
A typical script for groundwater development (1) Well drilling and groundwater abstraction precede systematic data collection. (2) Well drilling is dictated solely by the exigencies of demand. The "econo m y of scale" that may, perhaps, be achieved by the simultaneous drilling of many wells is negligible as compared to the advantage of development according to immediate requirements. Well owners compete for water supplies from the same c o m m o n pool without even realizing it.
441 (3) Legal doctrines regarding groundwater rights are vague and based on antiquated concepts. (4) The people who invest their m o n e y in well drilling are concerned only with the availability of groundwater at particular sites. Investigations concerning the resource as a whole are carried out, on a routine basis, and on a meagre budget, by state or national agencies, if at all. Intensive investigations are deferred until the water-supply situation visibly deteriorates. (5) Public concern with environmental impacts is activated only in rare cases, for example, when intensive groundwater abstraction diminishes the flow of a nearby stream or, very belatedly, when soil subsidence occurs. (6) Quantitative information on the resource is derived mainly from observations in exploited well fields, i.e. as a kind of " b y - p r o d u c t " of exploitation. Due to the short lead time between the discovery of the groundwater resource and its intensive development, information trails more and more behind the actual situation in the field. (7) Attempts are made to control groundwater abstraction by stringent legal and administrative measures. (8) Water users resent regulation as unwarranted interference in their private business and stultify effective control. (9) Continued overexploitation damages the resource irreversibly. TECHNICAL FACTORS AND SOCIETAL ASPECTS
A change of the script for groundwater development requires the modification of many more factors than those that are usually considered in the "planning space" of a water supply project (Wiener, 1972). We shall try to distinguish between technical factors and between societal aspects although both are intertwined and cannot be completely separated.
Technical factors The information needed in order to plan the crucial, early phase of groundwater development comprises: mapping of the aquifer, elucidation of the mechanisms of natural replenishment and of natural drainage, reliable (though not necessarily precise) data on average annual replenishment, aquifer constants and exploitable reserves, evaluation of constraints on exploitation, and of the critical water levels corresponding to each constraint. It should be noted that the list does not include items that can be obtained only from extensive records, such as stochastic elements, or the time scale of hydrological processes. Therefore, the requisite information can, in principle, be assembled by a systematic campaign of field investigations, including well drilling, within a relatively short time, say 2--3 years. In areas that are being developed by international finances, such as the U.N. special fund, such campaigns have become c o m m o n practice. The budgets that have to be allocated for this purpose are seen to be only a small fraction of the
442 aggregate value of the project. Affluent nations tend to cling to the traditional views that the investigations for engineering projects are the investors' concern, and confine themselves to the role of defending the public interest by administrative controls. In the last analysis it is this traditional attitude which so often prevents the rational development of groundwater, and which has to be modified. The present state of the art of field investigations leaves much to be desired in spite of the fact that many new techniques are available, such as improved geochemical methods, environmental isotopes, artificial tracers, remote sensing, etc. However, there is a wide gap between a viable scientific m e t h o d and its routine application by non-specialists. The field investigator needs precisely specified working procedures, standardized instruments and, above all, he needs reliable information on the applicability and limitations of each technique. In short what he needs is an armory of sophisticated but standardized diagnostic tools akin to the one that is at the disposal of any modern medical practitioner. Efforts in this direction may accomplish a major breakthrough.
Societal aspects Legal doctrines should enable the regulation of groundwater abstraction and they should recognize groundwater basins and aquifers as natural units. Whether this necessity calls for the nationalisation of groundwater resources is a different matter. However, legislation is of little value unless backed up by effective administrative measures which, in the case of groundwater resources, are notoriously difficult to enforce. The most obvious control measure, licensing of well drilling and of pumping aggregates, regulates actual groundwater abstraction only within limits. Criteria for well licensing have to be based on peak demand that is supposed to occur only during a small part of the year. Subsequently, the peak demand season tends to become more and more prolongued due to the increase of irrigated areas, to changes in cropping patterns, and to the construction of storage reservoirs. Even when these developments are detected, for example, by regular overflights of the area, it is almost impossible to reverse them. Control by water meters is still less practicable. Infuriated well owners will find ways to tamper with them, or to threaten or bribe the unlucky official who is sent to read them. The problem of control is, essentially, a problem of societal structure. A farming area, where each farm derives water from its own well strictly for its own purposes is practically uncontrollable. The farmers-well owners cherish their independence above everything else, they do not wish to realize that they are all in the same boat and may even organize for the purpose of defeating any " e n e m y " who threatens to shatter this illusion. Under these conditions legal doctrines and sweeping administrative powers are quickly reduced to the status of fictions. In a developing area steps should be taken to prevent this situation. Already
443
at a very early phase of development water users should be encouraged to construct small water-supply networks, serving more than one user. In this case, accounting procedures make the installation of water meters mandatory and some measure of mutual control is enforced. It is far easier to regulate groundwater abstraction by a small number of water supply utilities than by a multitude of privately owned wells. Incidentally such an arrangement also facilitates the more efficient exploitation of the aquifer since well sites can be selected according to hydro-geological criteria rather than on the basis of land ownership. Each network may be jointly owned and operated by the users it supplies, the point being only to prevent the one to one correspondence of individual water users and individual well owners. The case history of Israel (Wiener, 1972, pp. 401--405; Mandel, 1977, pp. 4 4 -51) illustrates this procedure. Many areal water-supply networks, each one supplying several farms, were constructed long before the infrastructure for the enforcement of the stringent Israeli water law had been built up. Thus many, though not all, water users were accustomed to the idea that the regulation of water supplies is a necessary evil. On this basis the transition to a strictly controlled water economy -- in a country that derives 2/3 of its supply from groundwater -- was accomplished with little friction.
REFERENCES
Hall, W.A. and Dracup, J.A., 1970. Water Resources Systems Engineering. McGraw-Hill, N e w York, N.Y., 384 pp. Mandel, S., 1977. The overexploitation of groundwater in dry regions. In: Arid Zone Development. Bullinger, Cambridge, Mass., pp. 31--51. Wiener, A., 1972. The Role of Water in Development. McGraw-Hill, N e w York, N.Y., 496 pp.
439
[2] PROBLEMS OF LARGE-SCALE GROUNDWATER DEVELOPMENT
S. MANDEL Center for Groundwater Research, Hebrew University, Jerusalem (Israel)
(Accepted for publication February 7, 1979)
ABSTRACT Mandel, S., 1979. Problems of large-scale groundwater development. In: W. Back and D.D. Stephenson (Guest-Editors), Contemporary Hydrogeology -- The George Burke Maxey Memorial Volume. J. Hydrol., 43: 439--443. The difficulties encountered in the planned development of groundwater resources are analysed by comparing typical "scripts" for surface and groundwater resources, respectively. The suggested remedies are: (a) campaigns of systematic field investigations in any area where the intensive exploitation of groundwater is envisaged; (b) standardization and codification of modern research techniques so that they can more readily be used by any investigator; (c) the construction of water supply networks serving more than one user in order to stimulate cooperation and mutual control among water users and to facilitate the centralized regulation of groundwater abstraction.
INTRODUCTION In 1 9 7 5 t h e late G.B. M a x e y and t h e a u t h o r w e r e engaged in studies o f g r o u n d w a t e r mining. A c o l l e c t i o n o f case histories revealed t h a t t h e overexp l o i t a t i o n o f g r o u n d w a t e r is a v e r y c o m m o n practice, especially, t h o u g h n o t exclusively, in d r y areas. G e n e r a l l y , w i t h v e r y few e x c e p t i o n s , o v e r e x p l o i t a t i o n d e v e l o p s u n i n t e n t i o n a l l y and is o n l y b e l a t e d l y recognized. Available d a t a r e f e r m a i n l y t o areas w h e r e a t t e m p t s are b e i n g m a d e t o r a t i o n a l i z e g r o u n d w a t e r m i n i n g a n d t o p l a n rescue schemes. D a t a f r o m areas w h e r e g r o u n d w a t e r m i n i n g " j u s t h a p p e n s " , o r w h e r e it has r u n its full d e s t r u c t i v e course, generally, r e m a i n inaccessible. T h u s t h e available d a t a are p r o b a b l y indicative o f a p r o b l e m t h a t will b e c o m e acute, o n a global scale, w i t h i n t h e n e x t t w o or t h r e e decades, unless t h e p r e s e n t t r e n d s in g r o u n d w a t e r d e v e l o p m e n t are reversed. T h e r e s p e c t i v e m e r i t s o f sustained yield e x p l o i t a t i o n versus m i n i n g m a y be arguable in each p a r t i c u l a r area. T h e w i d e - s p r e a d u n c o n t r o l l e d d e v e l o p m e n t o f irreplaceable w a t e r r e s o u r c e s is c e r t a i n l y an u n d e s i r a b l e state o f affairs. T h e p r e s e n t p a p e r a t t e m p t s t o analyse t h e reasons f o r this s i t u a t i o n and t o suggest r e m e d i e s against its f u r t h e r spread.
440 SCRIPTS FOR SURFACE WATER AND GROUNDWATER DEVELOPMENT The rational development of a natural resource requires information as input to planning, and planning as guide to action. However, the actual course of development tends to follow a "script" generated b y the interaction of human attitudes, technical, and societal factors. A comparison of typical scripts for surface water and groundwater development shows w h y it is relatively easy to follow rational procedures in the first case, while it is difficult to enforce them in the second one.
A typical script for surface water development (1) The drainage basin of the river is mapped and some quantitative data are collected long before large-scale diversions are thought of. (2) The design criteria of dams, spillways and intake structures are dictated by the stochastic hydrological characteristics of the river, not only by the discharges that are actually going to be diverted. As a consequence, larger works are able to supply water at a smaller unit cost, and the resultant "econo m y of scale" (Hall and Dracup, 1970) forces competitors for water supplies to cooperate already during the planning phase. (3) Legal doctrines recognize c o m m u n i t y rights on river water and refer to the watershed as basic natural unit. (4) Feasibility studies, based on a thorough investigation of the resource are mandatory because of the large investment that is involved. {5) The scope of investigations is widened in response to public concern with the environmental inpact of the project. (6) Quantitative investigations of the resource are based on flow gaugings and on meteorological observations, i.e. data that can be collected prior to any construction work. The long lead time between the study and the implementation of the project makes it possible to collect adequate data. (7) The completed scheme is operated by a statutory authority exercizing physical control over the installations. (8) Water users accept the necessity of regulation, since water abstraction by any one user visible affects water availability to all other users. (9) Even gross mismanagement is unlikely to damage the resource.
A typical script for groundwater development (1) Well drilling and groundwater abstraction precede systematic data collection. (2) Well drilling is dictated solely by the exigencies of demand. The "econo m y of scale" that may, perhaps, be achieved by the simultaneous drilling of many wells is negligible as compared to the advantage of development according to immediate requirements. Well owners compete for water supplies from the same c o m m o n pool without even realizing it.
441 (3) Legal doctrines regarding groundwater rights are vague and based on antiquated concepts. (4) The people who invest their m o n e y in well drilling are concerned only with the availability of groundwater at particular sites. Investigations concerning the resource as a whole are carried out, on a routine basis, and on a meagre budget, by state or national agencies, if at all. Intensive investigations are deferred until the water-supply situation visibly deteriorates. (5) Public concern with environmental impacts is activated only in rare cases, for example, when intensive groundwater abstraction diminishes the flow of a nearby stream or, very belatedly, when soil subsidence occurs. (6) Quantitative information on the resource is derived mainly from observations in exploited well fields, i.e. as a kind of " b y - p r o d u c t " of exploitation. Due to the short lead time between the discovery of the groundwater resource and its intensive development, information trails more and more behind the actual situation in the field. (7) Attempts are made to control groundwater abstraction by stringent legal and administrative measures. (8) Water users resent regulation as unwarranted interference in their private business and stultify effective control. (9) Continued overexploitation damages the resource irreversibly. TECHNICAL FACTORS AND SOCIETAL ASPECTS
A change of the script for groundwater development requires the modification of many more factors than those that are usually considered in the "planning space" of a water supply project (Wiener, 1972). We shall try to distinguish between technical factors and between societal aspects although both are intertwined and cannot be completely separated.
Technical factors The information needed in order to plan the crucial, early phase of groundwater development comprises: mapping of the aquifer, elucidation of the mechanisms of natural replenishment and of natural drainage, reliable (though not necessarily precise) data on average annual replenishment, aquifer constants and exploitable reserves, evaluation of constraints on exploitation, and of the critical water levels corresponding to each constraint. It should be noted that the list does not include items that can be obtained only from extensive records, such as stochastic elements, or the time scale of hydrological processes. Therefore, the requisite information can, in principle, be assembled by a systematic campaign of field investigations, including well drilling, within a relatively short time, say 2--3 years. In areas that are being developed by international finances, such as the U.N. special fund, such campaigns have become c o m m o n practice. The budgets that have to be allocated for this purpose are seen to be only a small fraction of the
442 aggregate value of the project. Affluent nations tend to cling to the traditional views that the investigations for engineering projects are the investors' concern, and confine themselves to the role of defending the public interest by administrative controls. In the last analysis it is this traditional attitude which so often prevents the rational development of groundwater, and which has to be modified. The present state of the art of field investigations leaves much to be desired in spite of the fact that many new techniques are available, such as improved geochemical methods, environmental isotopes, artificial tracers, remote sensing, etc. However, there is a wide gap between a viable scientific m e t h o d and its routine application by non-specialists. The field investigator needs precisely specified working procedures, standardized instruments and, above all, he needs reliable information on the applicability and limitations of each technique. In short what he needs is an armory of sophisticated but standardized diagnostic tools akin to the one that is at the disposal of any modern medical practitioner. Efforts in this direction may accomplish a major breakthrough.
Societal aspects Legal doctrines should enable the regulation of groundwater abstraction and they should recognize groundwater basins and aquifers as natural units. Whether this necessity calls for the nationalisation of groundwater resources is a different matter. However, legislation is of little value unless backed up by effective administrative measures which, in the case of groundwater resources, are notoriously difficult to enforce. The most obvious control measure, licensing of well drilling and of pumping aggregates, regulates actual groundwater abstraction only within limits. Criteria for well licensing have to be based on peak demand that is supposed to occur only during a small part of the year. Subsequently, the peak demand season tends to become more and more prolongued due to the increase of irrigated areas, to changes in cropping patterns, and to the construction of storage reservoirs. Even when these developments are detected, for example, by regular overflights of the area, it is almost impossible to reverse them. Control by water meters is still less practicable. Infuriated well owners will find ways to tamper with them, or to threaten or bribe the unlucky official who is sent to read them. The problem of control is, essentially, a problem of societal structure. A farming area, where each farm derives water from its own well strictly for its own purposes is practically uncontrollable. The farmers-well owners cherish their independence above everything else, they do not wish to realize that they are all in the same boat and may even organize for the purpose of defeating any " e n e m y " who threatens to shatter this illusion. Under these conditions legal doctrines and sweeping administrative powers are quickly reduced to the status of fictions. In a developing area steps should be taken to prevent this situation. Already
443
at a very early phase of development water users should be encouraged to construct small water-supply networks, serving more than one user. In this case, accounting procedures make the installation of water meters mandatory and some measure of mutual control is enforced. It is far easier to regulate groundwater abstraction by a small number of water supply utilities than by a multitude of privately owned wells. Incidentally such an arrangement also facilitates the more efficient exploitation of the aquifer since well sites can be selected according to hydro-geological criteria rather than on the basis of land ownership. Each network may be jointly owned and operated by the users it supplies, the point being only to prevent the one to one correspondence of individual water users and individual well owners. The case history of Israel (Wiener, 1972, pp. 401--405; Mandel, 1977, pp. 4 4 -51) illustrates this procedure. Many areal water-supply networks, each one supplying several farms, were constructed long before the infrastructure for the enforcement of the stringent Israeli water law had been built up. Thus many, though not all, water users were accustomed to the idea that the regulation of water supplies is a necessary evil. On this basis the transition to a strictly controlled water economy -- in a country that derives 2/3 of its supply from groundwater -- was accomplished with little friction.
REFERENCES
Hall, W.A. and Dracup, J.A., 1970. Water Resources Systems Engineering. McGraw-Hill, N e w York, N.Y., 384 pp. Mandel, S., 1977. The overexploitation of groundwater in dry regions. In: Arid Zone Development. Bullinger, Cambridge, Mass., pp. 31--51. Wiener, A., 1972. The Role of Water in Development. McGraw-Hill, N e w York, N.Y., 496 pp.