The present article is primarily concerned with the redistribution of the common Palestinian-Israeli water sources, a core issue of the water conflict between the two sides. More specifically, I wish to explore how redistribution can be worked out on the basis of "factors" stipulated in the doctrine of "equitable apportionment" of international water law. I argue that those factors favor Palestinians and certainly entitle them to a much larger share than the authorities permit them to tap at present; nonetheless, exact shares can- not be determined except on the basis of agreed data as well as more rigorous calculations than those attempted here. I also argue that redistribution is possible without causing "appreciable harm" to Israel, and that, within the context of a peaceful political settlement, it is not a zero-sum game.
Sharif S. Elmusa has been an advisor to the Palestinian delegation to the multilateral negotiations on water, and is currently conducting a study on the Israeli-Palestinian water conflict with a grant from the Friends of the Institute for Palestine Studies funded by the Ford Foundation. This article is drawn from his presentation at the IPS panel discussion "Arab-Israeli Peace Settlement: Interim and Final Status Issues" at the 1992 MESA conference, Portland, OR, 28-31 October.
"The lowland drinks its own water and the water of others" (Palestinian proverb, cited in 'Abbas and Shahin 1989, p. 57).
"It [the Bellagio Draft Treaty] is based on the proposition that water rights should be determined by mutual agreement rather than be the subject of uncontrolled, unilateral taking, and that rational conservation and protection actions require joint resource management machinery" (Hayton and Utton 1989, p. 664).
"It is precisely because the water is often inadequate to satisfy the just needs of all that rules [for equitable apportionment] are required" (Lipper 1969, p. 44).
The present article is primarily concerned with the redistribution of the common Palestinian-Israeli water sources, a core issue of the water conflict between the two sides.  More specifically, I wish to explore how redistribution can be worked out on the basis of "factors" stipulated in the doctrine of "equitable apportionment" of international water law. I argue that those factors favor Palestinians and certainly entitle them to a much larger share than the authorities permit them to tap at present; nonetheless, exact shares can- not be determined except on the basis of agreed data as well as more rigorous calculations than those attempted here. I also argue that redistribution is possible without causing "appreciable harm" to Israel, and that, within the context of a peaceful political settlement, it is not a zero-sum game.
Past discourse on the Israeli-Palestinian water conflict has concentrated on the history of the conflict and on Israel's severe restrictions on Palestinian access to water in the West Bank and Gaza Strip, and related, injurious practices (e.g., Davis, et al. 1980; Dillman 1989; Kahhaleh 1981; Naff and Matson 1984; Stauffer 1984). The frame of reference for discussion of Israel's policies in this literature is international law regarding belligerent occupation, especially the 1907 Hague Regulations and Article IV of the 1949 Geneva Conventions, and United Nations resolutions. That law speaks to the con- duct of the occupying power vis-a-vis the population and resources of an occupied territory, not to the problem of dividing international water re- sources. As a result, analysts often emphasized the impact of Israeli policies, yet provided no understanding of how much water Palestinians were entitled to. This dilemma, though not identified as such, was recognized by Jamal al- Hindi (1990; see also PHG and PAG 1992). Al-Hindi (p. 1421) argued that the principle of equitable distribution, as well as other principles stipulated in international water law, such as establishing institutions and free exchange of information, may be adaptable to the rules of belligerent occupation: "It is only natural that the laws of belligerent occupation should mirror the principles behind international water law." International water law should serve as a basis for defining the water quantities allocated to Palestinians as well as their role in managing that vital resource.
The previous focus on Israeli practices was prompted by the immediacy of the situation, the substandard conditions of water supply in the occupied Palestinian territories (OPT), events such as the sudden drying-up of wells or springs in the wake of drilling of deeper wells for the benefit of Israeli settlers and, most important, the absence of a negotiations framework within which the status of the common water resources could be tackled. Now that peace talks are "in progress," however, redistribution becomes central, and has been the key Palestinian water-rights demand in the multilateral negotiations on water resources (Palestine Delegation 1992).
Still, redistribution of the common water resources is one among several issues, the settlement of which is tied to theirs' as well. Before proceeding any further on redistribution, it is necessary to put it in perspective within what might be called the matrix of the Israeli-Palestinian water conflict.
A Matrix of the Conflict
The Israeli-Palestinian water conflict can be divided into five issues: (1) redistribution of the common waters; (2) encroachment by settlers on endogenous waters; (3) control of hydrospace (or water-land); (4) institutional control; and (5) data. The first issue refers to the grossly unequal distribution of the common Palestinian-Israeli water resources and the need for equitable redistribution. The second issue concerns the appropriation of water from the endogenous resources of the West Bank and Gaza for the benefit of Israeli settlers. The third issue, control of hydrospace, refers to Israel's quest for making its political boundaries coterminous with the head- waters so as to secure what it perceives as its water needs: even Israelis who speak of "territorial compromise" call for retaining the slice of the western section of the West Bank that contains the headwaters of the western aquifer (e.g., Cohen 1986, pp. 17-25; Schiff 1989, pp. 52-85).  There is also an obverse side to this: the potential impact of Israel's expressed intentions to retain or control sectors of the West Bank for reasons other than hydrology on water availability to Palestinians.  The fourth issue, institutional control, arises out of Israel's takeover of the management of water production, distribution, and use in the OPT. This it did through administrative means and military orders issued by the military governors of the OPT, and, since 1982, by the "transfer" of management to Mekorot, the parastatal Israeli water company.  The fifth issue, data, is partly a corollary of institutional control and concerns restrictions on Palestinian access to data (especially "raw" data),  the data themselves, and interpretation of even the same facts and statistics.
It is evident even from such a brief outline that the Israeli-Palestinian water conflict is in some respects unique, and cannot be simply subsumed under other regional water conflicts. For while some of the issues or aspects of them are "normal" insofar as they are found in many international water disputes, others are "abnormal": they derive from the peculiarity of the Israeli-Palestinian conflict. For instance, the issue of redistribution is common to many disputes among riparians, and, according to the above definition, is a normal issue. On the other hand, conflicts over the control of hydrospace and institutional control are abnormal. It is possible by dividing the issues into normal and abnormal types to construct a matrix of the Palestinian- Israeli water conflict as shown in table 1.
The superimposition of abnormal on normal issues helps explain the seeming intractability of the Israeli-Palestinian water conflict. Some of the abnormal aspects of the conflict arise in part from Israel's wish to gain or maintain a privileged water position, and are thus intimately linked to redistribution. Nevertheless, they acquire a "life of their own" and cannot be reduced to that particular issue. For instance, while institutional control is used as a tool for severely limiting Palestinian access to water, it can be also construed as an annexation measure, and would have to be dealt with in that context. And the issue of hydrospace is also a question of land, sovereignty, and security. Resolving the conflict over water hence involves more than agreement on redistribution. The other, abnormal issues would have to be part of the negotiations, too.
The need for redistributing the common water resources is predicated on: (1) the unilateral, lopsided appropriation by Israel of the common waters; (2) the substandard level of water consumption for the Palestinians; and (3) the wide water gap between the Palestinians and the Israelis. These are commonly acknowledged realities and need only a brief summation. Relevant data are summarized in the following map and tables 2, 3, and 4. Before proceeding, it must be cautioned that, for political as well as technical reasons, those and other data cited below are in dispute among Israeli, Palestinian, and other specialists. Palestinian researchers often cite, albeit mistrustfully, Israeli statistics, for the simple reason that Israel exercises a virtual monopoly on water-related research, severely restricting their access. Until mutual agreement is reached, the data presented here ought to be considered tentative.
The chief water sources in the West Bank and Gaza Strip are underground aquifers, or geological strata that yield significant amounts of water to springs and wells. There are also surface water sources that include wadis, or seasonal streams that carry floodwater runoff, and the Jordan River. Insofar as the water conflict is concerned, they can be divided into "endogenous" sources, that is, sources that commence and terminate within the boundaries of the OPT, and "international" sources, which flow into or out of the OPT. The assumption here is that the endogenous water resources of the West Bank and Gaza would be repossessed by Palestinians as part of an eventual peace settlement.
In the West Bank, surface water sources consist of two groups of wadis, the Jordan River,  and numerous springs.  The two groups of wadis issue from the central hill region, which is both the topographic backbone of the West Bank and the predominant hydrological region. One group flows untapped east of the watershed toward the Jordan, and is endogenous. The second group flows west through the West Bank and Israel toward the Mediterranean and is thus "international"; its waters are "harvested" inside Israel.
Underground water in the West Bank comprises three main aquifer systems: eastern, western, and northern. The eastern aquifer falls essentially within the West Bank. The western and northern aquifers are common to the West Bank and Israel, although as much as 95 percent of the area of these aquifers is located in the West Bank, from which they also receive 70-85 percent of their annual replenishment.  In other words, the western and northern aquifers, too, are essentially West Bank aquifers. They are at the center of the water dispute, because from hundreds of wells on its side of the border Israel appropriates more than 90 percent of their annual recharge.
Not all of the water in the aquifers is fresh; some is brackish (or somewhat salty and not readily fit for drinking and irrigation). The western, most plentiful aquifer may have 40 million cubic meters (mcm) of such brackish water, the northern, 20 mcm, and the eastern, 50 mcm or more (Shuval 1992, p. 3; Tahal 1990, sects. 2.5 and 2.8). Thus, the two common aquifers contain a much smaller proportion of brackish water, or, inversely, a much larger pro- portion of fresh water, than the exclusively Palestinian aquifer.
In the Gaza Strip, too, the chief source of water is underground water. There are no rivers, and the only surface water sources are wadis. The most important is Wadi Gaza (Hebrew: Nahal Bessor), with catchment areas in the West Bank, Gaza, and Israel; its water is impounded by Israel before it enters Gaza. Underground water is available in the highly absorbent sand- and-sandstone coastal aquifer, which is endogenous. Part of its water, how- ever, flows from the east, from Israel. Palestinian hydrologists contend that Israel intercepts this flow, leaving meager quantities for Gaza. Israel denies the claim. Until there are agreed data, this flow should tentatively be designated "disputably" common.
In all, and apart from the Jordan River, the aggregate volume of common Israeli-Palestinian water resources amounts to 565-655 mcm, replenished primarily from the West Bank.
Israel unilaterally, through the imposition of severe restrictions on Palestinian access, appropriates as much as 80-90 percent of the common water resources. It has also been overpumping-that is, pumping more than the rate of replenishment or safe yield-from the common aquifers and those within its borders.  Such overextraction has been criticized even by segments of the Israeli government because it endangers the long-term viability of the aquifers (e.g., State Comptroller's Report 1990). In addition, Israel significantly encroaches, through the settlers, on the endogenous waters of the OPT, particularly the West Bank's eastern aquifer. Finally, Israel has been extracting 150-200 mcm more water from the Jordan basin than the 375-400 mcm allotted to it under the 1955 Johnston Plan, not to mention 5-10 mcm from the Golan Heights.  On the whole, when it comes to the common water resources shared with Palestinians and other Arabs, Israel- and more specifically the ministry of agriculture and the water lobby-acts like a great sponge.
The net result of Israel's unilateral action is a substandard level of consumption for Palestinians in the OPT as well as a wide water gap between the Palestinians and the Israelis. A few statistics starkly illustrate the situation. Palestinian domestic consumption is meager, 20-30 cubic meters (cu.m) per person per year, or about 15-20 gallons a day. In villages and camps, consumption can be a third of this. Overall, the per capita aggregate water consumption in Israel is three to four times more than in the OPT, and the same holds true for domestic consumption. Furthermore, Palestinians in the West Bank are charged three times more per unit of domestic water than are Israelis. Stated in terms of relative GNP per capita, Palestinians pay a minimum of fifteen times more than Israeli consumers-a phenomenal difference for water systems managed by the same company. 
Beside the low quantities and higher prices, Palestinians obtain water of inferior quality. In central Gaza, the water's salinity can be as much as three times the standards of the World Health Organization (WHO).  Water is also polluted with nitrates from the return water of human consumption and agriculture.  The result is a deleterious impact on health conditions and quality of life (e.g., Bruins and Tuinhof 1991; Hulaili 1987; Save the Children 1990b). Even on the West Bank, salinity of irrigation water in the Jordan Valley and Jenin areas has been a growing problem, primarily as a result of overpumping by settlers and the refusal of Israeli authorities to let Palestinian farmers extract water from the deeper aquifer (Awartani 1991a, pp. 31-39).
A standard Israeli answer is that it has supplied many villages with piped water, where none had existed before 1967. This is only a half-truth. The proper comparison here is with the evolution of the water sector in Jordan, since it is reasonable to assume that had the West Bank remained part of Jordan, it would have attained at least the same level of consumption given its greater endowment with water than the East Bank. In Jordan, the per capita consumption for domestic purposes is twice that of the OPT, and nearly all villages receive piped water (al-Fataftah and Abu Taleb 1992, p. 160).
In fact, consumption levels in the West Bank rose by a mere 20 mcm during the period of occupation, compared to Israel's 400-500 mcm (Kahan 1987, p. 114; Tahal 1990, sect. 3.2). Domestic consumption grew slightly while the volume of water slated for irrigation fell somewhat, because the irrigated area did not increase and farmers widely adopted the water-saving technology of drip irrigation.
Indeed, the water gap between Palestinians and Israel is most apparent in agriculture. The overall irrigated area in Israel is ten times greater than in the OPT, or four times greater per person. Israel has been able to irrigate 95 percent of irrigable land, while the irrigated Palestinian land in the West Bank, where considerable expansion is possible, is less than one-fourth of the irrigable.  For reasons of state, Israeli farmers receive heavy water subsidies that encourage profligate water consumption and the growing of export crops with huge water appetite, thereby increasing the pressure on the common water sources.  As if this is not enough, Israel has allowed its settlers in the West Bank and Gaza to irrigate 47,000 dunums of confiscated land, with water allocations per unit area nearly double that on Palestinian land (Kahan 1987, p. 113). Meanwhile, Palestinian irrigated area has stagnated, and water salinity in many places has lowered crop yields and quality.
Israeli and other analysts often point out that their country suffers a water stress that affects its social and economic development (Falkenmark 1989; Shuval 1992).  Certainly no one would suggest that geographic Palestine is a water cornucopia. But it is not so obvious that the social and economic development of Israel has been hampered by the lack of water, not when it has been able to irrigate nearly all of its irrigable land.  More important, water stress is relative, and Palestinians are far more water-stressed than Israelis. And, to repeat Jerome Lipper's statement: "It is precisely because the water is often inadequate to satisfy the needs of all that rules [of equitable distribution] are required."
International Water Law and Equitable Distribution
A mutual agreement on dividing the common waters between Israel and the Palestinians can be achieved through direct negotiations, mediation, or arbitration. Because joint water management, by definition, requires cooperation, direct negotiations are preferable. Unfortunately, however, Israel's current position does not give much hope for the success of direct negotiations, as will be pointed out shortly. On the other hand, mediation could subject Palestinians to undue pressure based on considerations of power rather than fairness. In the end, and unless Israel exhibits more flexibility, arbitration, to which Egypt and Israel resorted to resolve the dispute over Taba, may be the most viable Palestinian option.
Whichever procedure the two sides opt for would need a guide for devising a new sharing regime. One such guide is international law; another relies on analytical methods based on optimization and cost-benefit analysis, such as environmental economic analysis and cooperative game theory (Rogers 1991). I am concerned in this paper with the division of waters according to international water law. International water law serves as a better framework for clarifying many issues in the conflict, such as Israeli insistence on maintaining prior or existing use and telling Palestinians to import water instead of redistribution, or Palestinian advocacy of nature-based redistribution. Also, international water law incorporates all the variables of the other approach.
The pertinent aspect of international water law involves the "factors" spelled out in the doctrine of "equitable apportionment." I will consider five factors common to the 1966 Helsinki Rules,  the 1988 Report of the International Law Commission (ILC), and the 1989 Bellagio Draft Treaty  (which Palestinians and Israelis may wish to consider as a model). Those factors are: (1) the natural attributes of the water source; (2) prior or existing use; (3) social and economic needs; (4) alternative resources and their comparative costs; and (5) avoidance of appreciable harm (Garretson, et al. 1969, pp. 782-91; Goldberg 1992, p. 72; Hayton and Utton 1989, pp. 695-97).
It has been often pointed out that international water law is nonbinding and lacks enforcement mechanisms. This is true, but it may also be the "best we've got" as a guide for negotiations. The factors it stipulates are based on treaties and conventions validated by governments, established custom, generally accepted principles, decisions by the judiciary, and the opinions of qualified persons (publicists). They contain certain "checks and balances" that, if approached in good faith, would protect the interests of both sides. One assumes that both Palestinians and Israelis would wish to abide by international water law.
Prior Use versus Natural Attributes
Israelis usually insist on one factor: prior or existing use. "Prior use" means maintaining the status quo, or extracting 80-90 percent of the common waters. Many Israelis have in fact convinced themselves that the common waters are theirs, as, for example, when they speak of how Israel is using 95 percent or more of "its" water resources. Unfortunately, this statement has been repeated, wittingly or unwittingly, by international commentators and water specialists. There is no doubt that Israel's dominant military power and present control of the headwaters represent the backdrop of this stance. The prevalent Israeli position is summarized by Hisham Awartani (1991c) thus:
Many Israeli economists, politicians, and journalists have already expressed profound interest in establishing some form of cooperation with the Palestinians on the question of water. But the version of cooperation advocated by most Israelis, including some with presumably moderate views, is strangely unfair and arbitrary. Most Israeli experts argue rather bluntly that despite whatever injustices have been inflicted on the Palestinians in regard to water, the Israelis have acquired de facto rights which are no longer subject to change. The only suggestion which they have to offer the Palestinians on this question is to "import" water from their Arab neighbors (p. 21; emphasis added).
This is how Elisha Kally (1991/92), a relative political moderate but an apparent water hardliner, puts it:
Palestinian claims to water presently under Israeli control-particularly the Yarkon-Tanninim aquifer [the Israeli term for the western aquifer]-will not be practical because of Israel's own water shortages and because they will not have any standing in international law (due to the legal preference for existing and historical consumption over new claims) (p. 32).
Insistence on prior use is but a variation of Israel's longstanding strategy of faits accomplis. Authorities on international water law stress that all factors must be weighed and that prior use is not paramount. For instance, Hayton and Utton (1989), two prominent members of the group that drafted the Bellagio Draft Treaty, state: "This language [weighing all the different factors] has become accepted virtually universally" (p. 669). Not so universally, it would seem.
Other arguments could be marshaled against prior use. It may be said that it was fortunate for Israel that prevailing social and economic conditions before 1967 did not permit Palestinians to extract larger amounts from the common aquifers. Now that Israel has exploited that very water successfully to spur its own economic development, it is time that Palestinians be given the chance to develop their own economy-a process hamstrung by, among other things, lack of water. In fact, in some of the rules of equitable distribution the "stage of economic development" is deemed as one of the factors to be weighed.  In any case, prior use remains a de facto condition and does not acquire legitimacy or become de jure, unless the co-riparian agrees to it. It is also important to mention that Israel appears not to have given "prior notification," as international water law requires, to Jordan, then the co-ripa-rian, when it began in the first half of the 1960s to extract substantial quantities of water from the common aquifers (PHG and PAG 1992, p. 23). Today, Palestinians cannot be expected to accept a grossly unfair status quo.
And if it is a matter of arbitrary interpretation of international water law, Palestinians could insist that the only factor to weigh is the natural attributes of the water sources. Some Palestinian authors and specialists have called the western and northern aquifers "Palestinian waters" (IPCRI 1991/92; al- Jarbawi and 'Abd al-Hadi 1990). More concretely, Hisham Zarour and Jad Isaac (1992) have proposed a mathematical water-sharing formula based on "nature's apportionment," or the natural attributes of the water sources. Their formula is attractive for its neatness and simplification of the web of factors. Also, nature-based apportionment is the way shared mineral resources are divided (Barberis 1991, pp. 177-78). If this formula were applied to the common Palestinian-Israeli waters, the Palestinian share would perhaps be 80 percent or more, the exact opposite of the present distribution. Obviously, Israel would reject such an outcome. Even more, it would use such a proposition as an extra excuse to retain the headwaters.
Briefly, it would seem then that selectively invoking factors based on prior use and hydrology leads to irreconcilable claims. A realistic redistribution would give each party less than the 80 percent they now demand. How much each party should be allotted would be calculated by weighing in the rest of the factors as well.
Social and Economic Needs
Assessing how water division can be based on the social and economic needs of both sides helps us to view water as a means rather than an end. This has a precedent in the Johnston Plan, under which the division of water was based on irrigation water requirements. The region has changed since the Johnston Plan, and the substantial population growth since then and that expected in the coming years has led many analysts to argue that securing fresh water for drinking ought to top the hierarchy of needs.
In order to estimate the needs, I use the "baseline," or basic needs, approach employed by Shuval (1992).  Shuval posits that baseline fresh water requirements per person per year would be: 100 cu.m for municipal use (domestic, commercial, and industrial), and 25 cu.m. for agriculture. Assuming that 65 percent of municipal wastewater would be treated and reused in industry and agriculture,  the gross per capita agricultural water requirements would be nearly 90 cu.m per year.  Based on these assumptions, and a "hypothetical" population in the year 2022 of five million Palestinians and ten million Israelis, the baseline requirements would total 625 mcm and 1,250 mcm for the two sides, respectively.
Shuval does not examine the implications of his estimate of needs for the redistribution of the common waters. Estimating the needs requires the inclusion of population as a variable.  Furthermore, after determining the water needs it is necessary to check them against the water each side possesses, apart from the common waters, and then divide the common waters accordingly. In effect, splitting the common waters according to the needs factor amounts to splitting the water sources within the boundaries of Man- date Palestine according to population ratios. If we take Shuval's estimates at face value and keep in mind the data difficulties, the shares would be 74 percent for Palestinians and 26 percent for Israel. 
Comparative Costs of Alternative Resources
Alternative water resources refer specifically to potential sources-such as desalination of brackish underground water or seawater, imported water, etc.-rather than sources presently exploited or those comparable to them. Those sources, by increasing the size of the "bucket," could facilitate an equitable sharing agreement. They are not an alternative to equitable distribution, as, for example, many of their Israeli advocates seem to suggest (e.g. Gur 1992; Kally 1991/92). They are one factor among others to consider in the determination of shares. How they affect the equation of equitable apportionment depends on their availability and comparative costs of harnessing them. Naturally, the relative availability of alternative resources must be assessed first: for a riparian without alternative sources, comparative costs are an academic question. The comparative costs are a yardstick of the parties' ability to harness alternative resources. The party that is more able would be entitled to a smaller share of the common sources (just within the confines of this factor).
There are potentially two alternative ways of obtaining water for Israel and Palestinians: importation, and desalination of brackish and saline water. 
Regarding importation, numerous schemes have been proposed for transporting water via pipelines or canals from the "water-rich" countries in the Middle East to the poorly endowed.  Those schemes require separate treatment. All that can be said here is that they are last-resort, long-run options to be undertaken after a discernible stabilization of regional politics. Under present conditions, such schemes would, strategically, increase the vulnerability of Israel, but more so of Palestinians since Israel could project its military power far afield to protect the water conduits, whereas the Palestinians have no such option. At the risk of dramatization, a limited defense force and water from Turkey would put the Palestinians' very survival at the mercy of the unstable political winds of the region. Be that as it may, the procedure of estimating comparative costs, which I will discuss only in regard to desalination, is applicable to the importation schemes as well.
Desalination technology can be used to extract fresh water from either brackish or saline water. In the West Bank, Palestinians could tap brackish water mainly from the eastern aquifer, perhaps less than 50 mcm. More than one half of Gaza's aquifer, which I have been counting as a "mainstream" source, has for all practical purposes become an "alternative" source in that it requires desalination to make it fit for drinking, and even for irrigation; it may have to be considered "alternative" in calculating the water shares from common resources. There is less brackish water in the OPT than in Israel, where there are scattered brackish water sources throughout. More crucial than these sources, however, is the tremendous brackish-saline aquifer underlying the Negev. This aquifer might suffice the water needs of the Negev region, which was allocated about 20 percent of the water by the late 1970s, for perhaps a century. It could even be used to irrigate crops in the central coastal area (Huerta 1991, p. 117; Nativ and Issar 1989, p. 128; Issar cited in Pearce 1991).
Other than underground brackish-saline water, there is seawater. The West Bank is a landlocked territory and does not have a seafront, while Gaza has a modest front which may be able to support a major desalination plant. Israel, on the other hand, enjoys a broad seafront extending from the Lebanese border to Gaza's, which gives it flexibility in plant location. Desalination technology, both of brackish and seawater, is available and represents a viable option, particularly for Israel. As for costs, it is reasonable to suppose that the absolute, micro-costs of desalination-that is, plant and operation costs-would be comparable in both the West Bank and Gaza and Israel. Comparative costs would have then to be evaluated with reference to the size of investment relative to the size of the macroeconomy as well as consumer prices.
Measured in gross domestic product (GDP), Israel's economy in 1986 was, by official accounts, more than fourteen times larger than that of the West Bank and Gaza, while its GNP per capita was three to four times as high (Kleiman 1991, p. 2). The gap has widened after the battering of the Palestinian economy during the intifada. Furthermore, Israel already possesses the industry and technology of desalination, while Palestinians would have to import it (IPCRI 1991/92, no. 14; Keenan 1991). All of this makes Israel more capable of tapping the desalination alternative than Palestinians in the OPT.
The other aspect of comparative costs is the relative ability of the consumer to pay for the desalinated water. Based on the present consumer prices in Israel and the OPT as well as on various estimates of desalination costs,  the following can be inferred. In Israel, desalinated brackish water is affordable for municipal use and economical for agriculture, while desalinated seawater is affordable for domestic use and may be economical for some crops. In the West Bank, desalinated brackish water is affordable for municipal use and perhaps for agriculture in the Jordan Valley. Gaza consumers, conversely, would be heavily burdened by the costs of desalinated water, even of the brackish type.
All in all, the OPT have limited brackish water, and only Gaza has access to seawater. Israel, on the other hand, possesses huge quantities of brackish water and practically limitless amounts of seawater. Also, the comparative costs both to the national economy and to consumers are far more favorable to Israel. The situation could be tipped even further in favor of Israel if plant operations costs could be lowered by implementing "megaprojects" such as the Red-Dead Canal project (now on the agenda of the Jordanian-Israeli bilateral talks) that would generate hydropower by tapping the differential head between the Jordan rift and the Red and Dead Seas. This reasoning would suggest that, from the standpoint of alternative sources, Palestinians in the West Bank and Gaza would be entitled to a larger portion of the common waters than Israel.
Avoidance of Appreciable Harm
Appreciable harm refers to costs that can be objectively measured as a result of denial of water rights. For there to exist appreciable harm, "there must," according to the 1988 report of the ILC (cited in Goldberg 1992, p. 72) "be a real impairment of use, i.e., a detrimental impact of some consequence upon, for example, public health, industry, property, agriculture or the environment...." The implication of this factor is obvious: no riparian can deny water to a co-riparian if that denial causes appreciable harm, and water must be reallocated in order to stop the infringement. The riparian causing the infringement would in all likelihood contend that it would be appreciably harmed by reallocation. In that case, both claims must be examined and ways found to balance the relative harm incurred by each of the co-riparians.
Palestinians have undoubtedly sustained appreciable harm, and the case for redistribution has been implicitly argued essentially on those grounds.  The impact of redistribution on Israel depends on how much water it would have to give up, or rather, give back. The sector most likely to be affected directly is agriculture. Israeli agriculture's share of the GDP is about 5 per- cent and constitutes about the same percentage of employment, suggesting that appreciable harm may not result from the reduction of water allocation to that sector. Those indicators cannot by themselves serve as reliable predictors, and more detailed impact analysis would be required. Nevertheless, an estimate by a study group at the Jaffee Center for Strategic Studies at Tel Aviv University (JCSS) shows that a reduction in the amount of available water by 100-200 mcm per year and its replacement by desalinated water would cost the Israeli economy $30-90 million  (JCSS 1989, pp. 219-20). Even if the costs were to prove appreciable, the cuts could be phased without causing "shocks" to the Israeli economy while at the same time not unduly curtailing growth of the Palestinian economy: Palestinian water demand is not likely to rise suddenly. Also, part of the increase could be satisfied first from untapped portions of the eastern aquifer and flood runoff, spring rehabilitation, and phasing out the irrigated agriculture of the settlements. At the same time, Palestinians would agree to sell Israel what remains of their share, reducing the amount over time according to the growth of their consumption, until each party receives its agreed share. This would leave Israel time to make the necessary adjustments in its economic structure and investment in alternative water sources.
Moreover, ways might be found to exchange various types of water that would reduce the harm even further, if not result in net benefits. Aquifers are functionally less versatile than rivers: they cannot be dammed, generate hydroelectric power, or be used for recreation and navigation. This confines the "basket of goods" that can be traded among the conflicting riparians essentially to water, and makes the division appear a zero-sum game: one side's gain is the other's loss. Nonetheless, the water is not all the same. It is differentiated according to several attributes: freshness-salinity, renewable- fossil, shallow-deep, upstream-downstream, and its location. One side may be willing to exchange a larger quantity of brackish water in one location for a smaller quantity of fresh water from another, or a smaller quantity of the same type of water from a shallow well for a larger one from a deep well, and so on. Yaron and Ratner (1990) have done a study on regional water exchanges within Israel based on this premise. It goes without saying that the institutional and political context of international cooperation complicates such a possibility and may render it impractical. Nevertheless, the parties may wish to explore further the distinctions among types of water in expanding the realms of costs and benefits as well as trade-offs. They may be able thus to enhance the efficiency of water use, as well as reach a more ambiguous deal easier to accept politically. And it is here that analytical approaches from welfare economics and cooperative game theory, which I mentioned earlier, may fruitfully supplement considerations of international water law.
Finally, Israel would be able to capture even greater benefits from regional cooperation in the wake of a peaceful settlement. The benefits would transcend the water sector; but even in the water sector alone and in water-related technology trade, Israel could profit. I have already indicated that Israel possesses desalination technology for brackish water and seawater. It also runs an advanced desalination research and development program. The largest desalination market is in the Middle East, owing to the paucity of water and abundance of energy resources; one would expect that Israel would be keenly interested in such a market.
Israel has a longstanding perception of its future role in the region as a promoter of technological development. This is arguable. It may be that cooperation in desalination would benefit Arab countries. Those countries, however, have had access to the best technology and expertise, and the fact that their technological capability is lagging has little to do with access; it is a product of historical and institutional reasons-a topic beyond the scope of this article. The Gulf states, for example, have built an impressive desalination capacity, and whether Israeli technology is available may not make a big difference to them. Israel itself would be the main beneficiary if it establishes a niche for itself in that market of perhaps $500 million a year (IPCRI 1991/92, no. 14). Marketing its desalination technology is thus one area where Israel could considerably gain.
A second area is hydroelectric power generation. I am referring here to megaprojects such as the aforementioned Red-Dead Canal. Jordan would benefit from the projects as well as Israel, but Gaza and the West Bank would not. The schemes need the agreement of Jordan and the Palestinians.  They also require large capital outlays, and no multilateral aid agency, such as the World Bank, would be in a position to assist without the approval of the Arab parties.
In short, Israel not only does not have to sustain appreciable harm as a consequence of redistribution; it also stands to gain in the context of a peaceful settlement through selling desalination technology and tapping hydroelectric power.
Israel's unilateral, lopsided appropriation of the common Palestinian-Israeli waters has left Palestinians in the West Bank and Gaza Strip with a substandard level of consumption and has created a wide water gap between them and Israelis. It runs counter to the doctrine of equitable distribution of international water law. Examination of the factors stipulated in the doctrine as a basis for an equitable distribution with respect to the Israeli-Palestinian common waters reveals several important conclusions.
First, Israel's insistence on maintaining prior use and the Palestinian demand that water be split according to the natural attributes of the water sources lead to irreconcilable claims. Second, Israel's refusal to reach an equitable distribution on the basis of the availability to Palestinians of alternative water resources is untenable. On the contrary, brackish and saline water resources and the economic and technical capability to tap them are far more available to Israel than to Palestinians. Importing water from other countries is also more viable for Israel than for Palestinians: Israel could project its military power to protect the water conduits, whereas the Palestinians could not. Third, the possibility of Israel sustaining appreciable harm can be avoided through an agreement by Palestinians to sell, in a phased manner, the part of their water share in excess of their water needs. Nor is it a zero-sum game. In the wake of a peaceful settlement, Israel can greatly profit from selling desalination technology in the principal Middle East market, as well as generating hydroelectric power from projects that require approval of the Arab side. Fourth, the two sides may wish to simplify the negotiations, and thereby reduce the "transactions costs" and speed up reaping the "peace dividend," by agreeing to consider the social and economic needs as the core factor. This has a precedent in the Johnston Plan. It would mean dividing the legitimate water of geographic Palestine among the two sides according to population size. Finally, an agreement on an equitable water-sharing regime could facilitate resolution of other related issues. Israel would no longer feel, for reasons of water, that it has to control the management of water resources in the OPT or retain sections of the West Bank. The key to reaching an equitable sharing regime lies in Israel's hands, but will it muster the requisite attitude and political will?
Sharif S. Elmusa has been an advisor to the Palestinian delegation to the multilateral negotiations on water, and is currently conducting a study on the Israeli-Palestinian water conflict with a grant from the Friends of the Institute for Palestine Studies funded by the Ford Foundation. This article is drawn from his presentation at the IPS panel discussion "Arab-Israeli Peace Settlement: Interim and Final Status Issues" at the 1992 MESA conference, Portland, OR, 28-31 October.
1. Singling out the redistribution of the Palestinian-Israeli waters does not preclude or contradict a basin-wide resolution. If those resources are thought of in "drainage-basin" terms, then they belong to the Jordan and Mediterranean basins; and the other riparians -Jordan,Syria, and Lebanon-would have to be included in the investigation. Depending on the choice the two sides make, the conflict can be resolved on its own, or as part of a basin-wide agreement. This would mean renegotiating the 1955 Johnston Plan, negotiated by the American emissary Eric Johnston among the four countries. The joint Palestinian-Israeli water sources were not covered in the plan. If a new basin-wide agreement is to be arranged, they would have to be part of it.
2. This is a "minimalist" demand expressed by people close to the thinking of the Labor party. A "maximalist" demand is exemplified in a full-page advertisement by the Ministry of Agriculture (1990) under the Likud government in the Jerusalem Post (1990) advocating retention of the entire West Bank to ensure control over the common aquifers.
3. For example, Saul Cohen proposes retention and control over essentially the entire Jordan Valley. Such retention would deprive the West Bank of its riparian status vis-a-vis the Jordan River. This is also the area that Prime Minister Yitzhak Rabin refers to when he speaks of continued expansion of "security" settlements.
4. The preexisting Water Department in the West Bank was left only with administrative responsibilities, such as collecting water charges and ensuring adherence to water quotas by farmers.
5. Israel denies this, but there is plenty of documented evidence to the contrary (e.g., Kahan 1987, V; IPCRI 1991, no. 8; Palestine Delegation 1992; Tahal 1990, pp. 8-12).
6. Various amounts of water were proposed for the West Bank during the negotiations of the Johnston Plan. In the 1954 Arab Plan, for example, the West Bank was to get 305 mcm from Lake Tiberias (American Friends of the Middle East 1964, p. 66). In the final Johnston Plan no specific mention, at least publicly, was made of the West Bank; however, the assumption was that the water would be allocated to irrigate the area on both sides of the Jordan River according to estimates made in 1955 by the American engineering firm Baker and Harza. According to those estimates, the irrigable area in the west Jordan Valley was about 29 percent of the total (based on ibid., p. 79). It therefore would be reasonable to say that the implicit share of the West Bank in the Johnston Plan was 29 percent of Jordan's total, or about 140 mcm, since Jordan was allocated approximately 480 mcm (from the Jordan and Yarmuk; not including the side wadis on the East Bank). Some Palestinian authors estimate that the West Bank share should be as much as 320 mcm (Center for Engineering and Planning 1992, p. 25). At any rate, the issue of the Jordan River is complicated by the fact that Jordan received hundreds of thousands of Palestinian refugees from the West Bank and Gaza in 1967 and from Kuwait in the aftermath of the Gulf war, as well as by the unknown number of Palestinians who may return to the West Bank from Jordan and other countries on the heels of a peace settlement. It requires separate treatment.
7. The discharge of the springs is included in underground water, in order to avoid double counting.
8. My calculation based on statistics in Shuval (1992, pp. 3-4) which he attributes to David Gvirtzman, Earth Sciences Division, Hebrew University.
9. By official estimates, overexploitation of the coastal aquifer averaged 85 mcm per year in the period 1983- 86. Some authorities, however, put the average at 150- 200 mcm per year over the same period. (AMER 1987, p. 60)
10. The estimate for the Jordan is based on Kolars (1992, table 8), Naff (1991a, p. 15) and Tahal (1990, sect. 2.4); for the Golan on Altemative Information Center (1988) and United Nations (1992, p. 22). Israel justifies its action by claiming that the water was allocated to the power that had sovereignty over the West Bank, thereby equating occupation with sovereignty (Nijim, 1990).
11. The GNP/capita in Israel in 1988 was $9,427, in the West Bank in 1987, $1,990, and in Gaza $1,376. (Tahal 1990, sects. 1.2 and 1.3) In Gaza, the relative charges are 4-5 times those in Israel (see also note no. 27).
12. WHO's standard is 200 mg/liter chloride.
13. Israeli analysts usually attribute the current problems plaguing Gaza's aquifer to overpumping during the Egyptian administration (1948-67) (Shuval 1992). It is true that overpumping occurred during that period, yet it is equally true that Israel has been managing the water in Gaza for a longer period, from 1967 to the present, and the quality of water consumed by the Palestinian population has only deteriorated. The responsibility for the damage to the Gaza aquifer thus cannot be solely assigned to Egypt; Israel also must acknowledge its own contribution.
14. In Jordan, drip irrigation and greenhouses have also been widely diffused; at the same time the irrigated area doubled during the period 1967-present. It could have expanded even more had the construction of the Maqarin (Wihda) dam not been blocked.
15. And while the subsidies may be considered an internal Israeli affair, and they have been heavily criticized by many Israeli specialists and officials, their impact is not.
16, This is not to imply that Hillel Shuval uses water stress as an argument against redistribution. He has been, as we shall see below, one vocal advocate of an equitable redistribution of the common waters.
17. The notion of water stress is useful when used to quantify societal water needs and when it draws attention to the population factor. We still need, however, the economic concept of scarcity as a supply-demand schedule that directs attention on how water is allocated.
18, These factors were formulated by the International Law Association, a nongovemmental body devoted to matters of international law. They have been a primary reference for subsequent factor lists.
19. Drafted by an interdisciplinary team of water specialists in Bellagio, Italy, and meant to serve as a model; it is not, however, international law.
20. Third Report to the ILC, 1982, cited in Hayton and Utton 1989, p. 700.
21. There is a second approach for estimating the "needs," namely, projecting future demand. The "baseline" approach is, in my opinion, preferable. It is premised on equal considerations of human needs on both sides and is ecologically grounded. In contrast, demand projection is based on prior or existing demand and thus incorporates "prior inequalities," in addition to sectoral allocations that may not be ecologically nor economically rational. One could even suggest that instead of assuming the population and then assessing water requirements, available water should first be estimated, and water constraint taken into account in the formulation of demographic policy and mode of economic development. A main drawback of the baseline approach is that it does not account for the costs of adjustment when the baseline needs are smaller than present consumption.
22. The assumption of 65 percent recycled water may be reasonable for Israel, but may be too high for the West Bank and Gaza, even in the year 2022, if we keep in mind the staggering economic demands that the OPT are expected to face and the deinstitutionalization process they have undergone. Even Jordan, with its viable water institutions, has experienced many problems -social, technical, and bureaucratic-with water recycling.
23. The assumption is that this amount would be sufficient for producing food for domestic consumption, not for exports. The total quantity would allow Israel to irrigate nearly 1.3 million dunums, and Palestinians half as much (this is my estimate, assuming an average of 700 cu.m/dunum/year).
24. In the 1966 Helsinki Rules, the population factor is listed separately; obviously, calculating the social and economic needs incorporates this factor.
25. Shares are preferable to exact amounts as was done in the Johnston Plan, because of the variability of available water. The shares were calculated as follows. Israel is estimated to require 1,250 mcm annually by the year 2022. If it has 1.1 billion cubic meters from "legitimate" resources (endogenous resources plus allocations from the Johnston Plan), then it would be left with a deficit of 150 mcm. Thus, Israel would need 150 mcm extra from the common waters in order to secure 1.25 bcm. Palestinian baseline needs, on the other hand, are estimated at 625 mcm. Their endogenous resources can supply 200 mcm or less of that amount, which would leave them 425 mcm short. If the common waters are divided according to those relative "deficits" of 150 mcm and 425 mcm-that is, in a manner that would equalize them- the respective shares would be about 74 percent for Palestinians and 26 percent for Israelis.
26. The present discussion considers only brackish water that needs desalination prior to use, not brackish water that can be directly used in industry, or even to irrigate some crops.
27. Those schemes include pipelines from the Seyhan and Ceyhan Rivers in Turkey, the Euphrates in Syria, the Nile, and the Litani down to Jordan, Israel, and the West Bank (see, for example, Duna 1989; Haddadin 1992; Kally 1991/92).
28. The costs of desalinated brackish water may amount to $0.30-.40/cu.m, and seawater $0.60-.80/cu.m. The costs are driven by the price of energy and would change in accordance with the price of oil. In Israel, average costs of production of regular water run about $0.33/cu.m; domestic consumers pay nearly that amount, whereas farmers pay a subsidized price of around $0.15/cu.m. Palestinians in the West Bank pay $1.00/cu.m for domestic water and $0.17 for irrigation water. In Gaza, the price of domestic water averages $0.20, and of irrigation water about $0.14 (because the water table is much shallower and hence pumping costs are lower) (Awartani and Juda 1991, p. 48; IPCRI 1992, no. 14; Keenan 1991, pp. 20-23; Tahal 1990, sects. 9.2 and 9.3).
29. Damage could be quantified in monetary terms for the agricultural sector, but would be difficult to quantify for health or quality of life.
30. An analysis by Gideon Fishelson (1992, p. 25) of the economic value of water in agriculture based on a 1982/83 input/output model for the Israeli economy indicates that a reduction of 700 mcm with no water saving technology would have lowered the value added of Israeli agriculture by one third. It also suggests that "nonconventional technological solutions for water supply might be close to being economically justified."
31. Because the West Bank shares a front on the Dead Sea with Israel and Jordan, Palestinian consent to the proposed joint Israeli-Jordanian canal would be necessary