DESALINATION: AN ALTERNATIVE TO EBRO WATER TRANSFER?

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1 27/07/2004 Num. 3 ENVIRONMENT contents DESALINATION: AN ALTERNATIVE TO EBRO WATER TRANSFER? THE ENVIRONMENTAL IMPACT OF DESALINATION PLANTS. Melchor Senent Alonso DESALINATION: A REAL ALTERNATIVE? Juan Jódar THE NATIONAL HYDROLOGICAL PLAN: THE EUROPEAN PERSPECTIVE ON A MISSED OPPORTUNITY. Cristina Gutiérrez-Cortines AN ENVIRONMENTAL ANALYSIS OF MASS DESALINATION IS ESSENTIAL. Jaime García-Legaz THE ENVIRONMENTAL IMPACT OF DESALINATION PLANTS Melchor Senent Alonso Chair of Hydrology, Ph.D. Mining Engineering University of Murcia Desalination plants are needed to satisfy tourist, industrial and ordinary human needs on the Mediterranean coast, but at the present time they cannot be an exclusive answer to the problem of agricultural demand in the south-east, because of their high cost and doubtful environmental impact. We have to know the environmental effects of the desalination plants included in the new plan before they begin running. The Ebro water transfer project is the only way of tackling the structural deficit of water supply on the Mediterranean coast. Results and recommendations of environmental impact studies The main environmental problem of desalination plants is saline discharges. This liquid waste has double the salinity of sea water (seawater desalination plants have an average recovery rate of 50%), and contains chemicals (biocides, anti-scaling and anti-foaming agents) from the pre-treatment process, as well as concentrates of suspended solids and detergents from membrane cleaning. There may also be significant increases in the concentration of nutrients, nitrates and phosphates. This common composition of the waste is a clear indication of its environmental impact. A thorough environmental impact study and above all monitoring programmes are needed to assess the real continued effects of the waste from desalination plants on the marine environment.

2 There are few such studies available as of today. Some have been carried out on the desalination plant in Jávea, Alicante and the Maspalomas II plant in Gran Canaria. The results of these studies may be summarized as follows: There is proof of the sensitivity of oceanic Posidonia to increases in salinity levels. Oceanic Posidonia is a plant which is unique to the Mediterranean. There is doubt as to what the future of this plant life and its ecosystem will be if the situation continues. Plan life in the depths is much more susceptible than the plant life near the surface. It unclear to what extent the results of a waste discharge from a particular desalination plant can be applied to other cases. Experiments with animals have clearly demonstrated that they are extremely susceptible to increases in salinity levels, although their tolerance levels have not been determined. Environmental precaution should guide action, i.e. safety margins have to fully guarantee the survival of affected marine prairies. The environmental impact of desalination plants is unclear. Environmental caution suggests that detailed environmental studies should be carried out before starting on the construction of any plant The following are measure recommended when planning and executing highly saline waste discharges: An analysis of the possible effects of the saline discharges on plant and animal life. Environmental monitoring programmes. Avoidance of areas with ecosystems related to oceanic Posidonia. An adherence to the principle of environmental precaution as formulated in the Rio Summit in the case of any highly saline discharge. A specific analysis of the method of discharge, taking into account the topography of the sea bed, the location of protected species of plant life, the renewal of seawater, etc. It is clear that the environmental impact of desalination plants is not sufficiently known. Environmental precaution suggests that a detailed study be made for each case, including the corresponding monitoring programmes, before starting on construction. These studies, coupled with those for alternative sites and detailed analysis of source water, require sufficient time to ensure that there is no improvisation involved when it comes to constructing the desalination plant. We sincerely believe that an over-hasty approach is being applied to find a solution which is at present not valid as a substitute to the Ebro transfer project. As we have maintained for some time, a certain number of desalination plants can be a complement to the Ebro transfer, but not a substitute. World experts in desalination are concerned by the impact which giant desalination plants could have on the marine environment. This concern is based on the effects produced by the discharges from one of the biggest desalination plants in the world in the Persian Gulf, where the continental shelf can be seen from the air to be covered by a layer of saline. The environmental impact of the energy consumed by desalination plants Another indirect environmental impact is the result of the intense consumption of energy by desalination plants. The figures for average energy consumption by inverse osmosis desalination plants using sea water are 4 kwh/m 3, compared to an estimated 2 kwh/m 3 in studies carried out for the Ebro transfer. 16

3 The figures for average energy consumption by inverse osmosis desalination plants using sea water are 4 kwh/m3, compared to an estimated 2 kwh/m3 in studies carried out for the Ebro transfer A hypothetical production of 600 hm 3 /year by inverse osmosis desalination of seawater would need an energy increase of 2,400 6 kwh/year (2,400 gigawatt hours). This would contribute to the greenhouse effect: if coal-fired power stations were used, CO 2 emissions would increase by 2.4 million tonnes; the figure would be a third using combined-cycle power stations. The increased energy needed to run a desalination plant cannot at present be produced using non-polluting renewable energies. The discontinuous nature of renewable energy sources (solar and wind) means that they are not capable of dealing with large-scale demand without the support of conventional energy. Experts agree that the energy supply with the brightest future in this respect is the hydrogen battery, because they produce continuous energy. However, a viable form is not expected for at least 5 to 10 years. The over-hasty support for large-scale desalination plants could provoke serious problems for energy supply on the Mediterranean coast, since this is an area with excess demand for electrical power. The result could be frequent power outages. DESALINATION: A REAL ALTERNATIVE? Juan Jódar Civil Engineer, Consultant Is desalination a real alternative to the transfer of water between river basins as a way of alleviating the problems caused by lack of water in Mediterranean Spain? A precise and reasoned answer to this question requires an awareness of the advantages and disadvantages associated with desalination, as compared to solutions with a proven efficiency, such as the transfer of surface waters. Desalination: a complementary source Desalination is a new way of producing good-quality water for human consumption. However, it is a complementary source, rather than an alternative. Its high cost makes it useful mainly for industrial, tourist and urban consumption. For agriculture, it is only useful at present for high added-value crops. Desalination is a complementary source, not an alternative. Surface waters replenish aquifers and substitute brackish water with fresh water The high cost of water produced by desalination means that it cannot fulfil such important environmental objectives as replenishing aquifers, which is an essential element in the fight against desertification in the south-east of Spain. This replenishment is produced by rain, which is scarce (250 mm per year) and by large-scale irrigation. The Tajo-Segura transfer is proving essential in replenishing the aquifers. A greater quantity of good-quality surface water is needed at a price which allows irrigation, now carried out using bad-quality underground water sources which salinate soil. 17

4 Surface water produces two beneficial effects: first, for the aquifers, since it cuts down on extraction; and secondly, for the soil, since it substitutes brackish water with fresh water. This is why an additional water transfer is needed. Desalination: more disadvantages than advantages The advantages of desalination are the quality of the water and its guaranteed supply. The disadvantages are the high price, its energy-dependence, geographical limitation (dependence on the location of plants and water distribution), and the environmental limits set by the marine environment, both in terms of the water supply and the discharges. Inverse-osmosis desalination, which is the system used by modern desalination plants, has made significant progress in terms of energy savings. It uses different types of increasingly efficient recovery methods, which have reached a ceiling of about 3 kwh/m 3 in the osmosis process. Energy is also used to pump water to the plant from the sea, and to the areas in which it is used. It will be extremely difficult to achieve a rate of consumption below 4-5 kwh/m 3 of desalinated water. The impact of discharges on the marine environment, in particular on the prairies of oceanic Posidonia in the Mediterranean, has been studied by reputable bodies and researchers. However, their long-term effects, and the impact of a significant volume of discharges, are not known. Most of the long-term cycle crops, particularly trees, which are a good barrier against the desertification of the area, cannot withstand the permanent increase in water costs resulting from the use of desalination, except for exceptional short periods of drought. Trees and other long-term crops which check desertification could not be watered. If the aquifers dried up, the result would be serious environmental, social and economic damage The alternative offered by desalination to the water transfers involves a series of unknowns which are difficult to assess beforehand. The most serious is the effect on the aquifers. They would probably dry up, causing wide-ranging social, environmental and economic damage. THE NATIONAL HYDROLOGICAL PLAN: A EUROPEAN PERSPECTIVE ON A MISSED OPPORTUNITY Cristina Gutiérrez-Cortines University Professor. Member of the European Parliament The environmental criteria applied by the European Commission to the Ebro transfer should be made known. Politics has outweighed scientific criteria. The attitude of the European Commission Three years before receiving the projects for funding, in December 2000, the Environmental Commissioner, the Socialist Margot Wallströn, agreed to carry out an informal analysis of the National Hydrological Plan, with the approval of the Spanish 18

5 government. This initiated a period of technical dialogue, questions, letters asking for data and complementary information, posted on the websites of the Commission and the Ministry of the Environment. Ms Wallströn made it clear in parliamentary answers and her appearance before the Petitions Committee of the European Parliament that she was analysing the plan and that a technical dialogue was in progress. In view of the complexity of the project and its interdisciplinary nature, in February 2002 the Commission asked the Spanish government for an independent third-party analysis. The General Directorate for the Environment, through the Institute for the Environment and Sustainable Development (IES) recommended a team, indicated the conditions necessary to guarantee its objectivity and a free working environment, and designated Amalio Garrido, an expert in water policy, as coordinator. The Spanish Ministry of the Environment agreed to incorporate the suggestions and changes made by a team of experts from the University of Berkeley, while the Commission undertook to recognize the environmental viability of the project if it included the recommendations and guarantees asked for by the American professors. A consensus was reached in December 2002, after numerous meetings. It was given the form of an official document in a joint official meeting held in Brussels on 30 January The consensus established that the final agreements on the informal revision would be made public during the visit to Madrid of the new Director General, Catherine Day, at the end of February However, the agreement was not complied with. The General Directorate for the Environment wanted to extend the process, demanding new studies and guarantees on the volume of water in the Ebro Delta, despite the fact that this was part of a different protection plan. As part of the technical dialogue, the Ministry agreed in good faith to extend the debate to include the Ebro Delta. It financed and supported a joint meeting held on 16 December At the request of the Commission, the conclusions were never published. The European Commissioner for the Environment, a member of the Socialist group, gave way to pressure from the Socialist Party, the government of Aragon, Catalan groups and some environmentalists. Why were the agreements not complied with, and why were the contents of the agreement of 30 January not made public? My own view is that the European Commission s General Directorate for the Environment, which until then had maintained an even-handed approach, and was objectively examining the scientific analysis of the risks involved, gave way to political pressure from the Socialist party, the regional government of Aragon, Catalan groups and some environmentalists. The show of formal objectivity was dropped to please particular parties who wanted the project stopped before the regional elections. In some parliamentary answers, the Commissioner herself admitted that the question had become politicized, making it difficult to maintain the debate at a technical level. The desire to postpone approval eased the consciences of the most scrupulous experts, turned the water question into an electoral and regional political football, and meant that other politically sensitive problems were not dealt with. When in February 2000 the projects which were provisionally accepted by the European General Directorate for Regional Policy were received, the General Directorate for the Environment tried to play for time. Meanwhile, caught this political crossfire, the most honest people took refuge in technical certainties, as if knowledge and science were instruments which guaranteed control over the future. 19

6 Unplanned desalination plants The agreement of 30 January 2003 was a missed opportunity. The Spanish Government undertook to set up transparent methods for water management, control of aquifers and high-technology monitoring of water consumption. It agreed to share the inspection of all the processes with other bodies and set up monitoring systems at the highest-risk points. The voluntary consultation process for the National Hydrological Plan has created a precedent for future action by the Commission. In addition, the water transfer projects had to comply strictly with the caution and precaution principle and the procedures and guarantees included in the application guide for European ERDF and cohesion funds. Obviously the new applications for funds for desalination plants will also have to comply with these strict requirements. These studies, which the European Commission has to review before awarding aid, will have to demonstrate that the new proposals for a massive seawater desalination project are the best possible overall solution. The application for desalination as a technical instrument to supply water to basins which have a deficit, as stipulated by the regulations referring to aid, should form part of a more general plan including not only the National Hydrological Plan but strategic regional plans as well. Are large-scale desalination plants included in any general planning document? No. The Spanish Government undertook to set up transparent methods of water management, control of aquifers and high-technology monitoring of water consumption. At this point, the Commission must ensure that it strictly applies the same process it demanded previously, and call for a strategic analysis of large-scale desalination. This should assess its effect on the territory, its impact on the balance between the interior and outlying areas, and the concentration of resources and population on the coast, with the corresponding abandonment of high-lying and rural areas. It might have to use basic criteria of sustainable development, comprehensive and integrated approaches including the territory and its variables as a dynamic and open system, subject to external pressures which have to be addressed by new or adapted means. Cost-benefit studies and impact analyses have to include an estimate of the environmental consequences of massive desalination compared to other alternatives, such as water transfer. It is essential to deal with the consequences of agricultural decline in the interior, and of course to study the effect that the high price of water will have in terms of the closure of numerous companies and the sale of productive agricultural land for property. Do we want diversity or an urbanized tourist area? Comparing water transfer and large-scale desalination, the Commission should bear in mind that the water transfer is an integrated plan, which supplies water to basins with a deficit, and includes numerous measures for protecting the environment. It replenishes the aquifers, restores wetlands, plains and protected areas. Included in its budget were 172 million euros for immediate use on the environment, as well as a surcharge on the final cost of the water. The water transfer project was in harmony with the sea; the desalination plants put its future at risk. 20

7 AN ENVIRONMENTAL ANALYSIS OF MASS DESALINATION IS ESSENTIAL Jaime García-Legaz Commercial Expert and State Economist Consultant for the World Meteorological Organization Director of the Economics and Public Policy division of FAES The Ebro transfer was the subject of rigorous environmental demands. Massive desalination generates a variety of environmental effects, some of them unknown on a large scale. It is absolutely unacceptable that the Government is avoiding discussion of the environmental impact of its planned large-scale desalination plants. The truth about the Ebro transfer The National Hydrological Plan Act took as a reference the positive experience of nearly 30 years from the Tajo-Segura water transfer, and after an extended period of scientific studies which fully backed the project it was introduced to regulate the Ebro transfer as a transfer of surplus resources governed by rigorous environmental restrictions. Only surplus resources would have been transferred, and the environmentally essential river flow would have been preserved. The resources could only be transferred during a particular part of the year: transfers were banned from before the start of summer until well after its end. An Ebro Delta Recovery Plan was to be drawn up. The delta is now badly deteriorated as a result of dams constructed in the 1960s, such as the Ribarroja dam, which retains enormous amounts of sediment. A significant amount of the water to be transferred was intended to recover the degraded Mediterranean wetlands, and to help stop the advance of desertification in the south-east of Spain. One of the key uses of the transferred water was for purely environmental purposes: to ensure the replenishment and recovery of the over-exploited aquifers. It was expressly prohibited to water new golf courses with the transferred water. It was also expressly prohibited for the river basins receiving the water to extend the land under irrigation. The purpose of some of the transferred water was to recover the degraded Mediterranean wetlands and halt the advance of desertification The transfer was also subject to strict compliance with European and national law on the environmental impact of projects. The law was strictly complied with, using studies by prestigious scientists and independent experts. Work on the transfer was only begun after all this initial preparation. The process took years of serious and detailed work. The potentially very serious environmental impact of large-scale desalination plants The National Hydrological Plan also included the use of desalination as a complementary rather than mass source of water. The plants were medium or small in size, and they were subject to the same analysis of environmental impact as the Ebro transfer. The present government has eliminated the Ebro transfer without presenting any proposal before parliament to reform the present law. The alternative project consists in constructing many large-scale desalination plants on the Mediterranean coast. In the opin- 21

8 ion of the majority of experts, it is an improvised measure, without the necessary scientific basis and with serious defects. These relate mainly to the high extra cost of desalinated water, the high extra consumption of energy used by the planned desalination plants, and the potentially extremely high environmental costs of massive desalination. How is it possible that there has been no strategic environmental analysis before the implementation of a massive desalination plan? It is essential to check the combined effect of massive discharges of saline on the marine ecosystems, in particular on the prairies of oceanic Posidonia. Scientists have pointed to the lack of precise knowledge we have about the effects of massive desalination on the marine ecosystems, but they have already raised the alarm because of the evidence of its devastating effect. It is also essential to study the impact of massive saline discharges on fish, which are also sensitive to increases in salinity. Is mass desalination to be introduced without analysing these effects? Desalination produces heavy metals. How is it possible that its probable effects on human health are not being studied? What will be the additional greenhouse gas emissions (carbon dioxide, nitrogen dioxide) arising from the proposed large-scale desalination plants? Under the EU directives governing emissions (within the framework of the Kyoto protocol), a comparative study should be carried out on the harmful emissions which produced by desalination plants, contrasting these with the figures for the pumping and transport of water by the Ebro transfer project. Public opinion should know what the environmentally preferable alternative is. Desalination produces residues, including heavy metals. Very little is known about the biocoenosis involved, but most scientific experts suggest that the effects could be extremely serious in the future. How is it possible that its probable effects of generating heavy metals on human health are not being studied? Is it not essential to carry out studies on this question? The large-scale transportation of desalinated water from each of the plants to the areas where it is needed will require the construction of hundreds of kilometres of transport infrastructure (pipes, valves, etc.). The environmental impact of these projects should be made known in advance. We should also not forget the visual impact: the way that the construction of desalination plants visible from far away will spoil the coastline. This impact should also be studied. All these questions are extremely worrying to environmental experts. Our marine and land ecosystems and the preservation of our atmospheric environment are not negotiable. The government has a duty to analyse the environmental impact of desalination plants. FAES, the Foundation for Social Studies and Analysis, does not necessarily identify with the opinions expressed in the texts it publishes. FAES, Fundación para el Análisis y los Estudios Sociales and the authors. D.L.: M