Centro de Estudios Hidrográficos
In 2001, the Centro de Estudios Hidrográficos continued giving its utmost dedication to the Directorate General of Hydraulic Works and Water Quality (DGHWWQ) of the Ministry of Environment.
The Law of the National Water Resources Plan was approved in July. In the final phase of its procedure, there was collaboration in the analysis of the assertions received and participation in forums, technical meetings and symposia celebrated for its presentation and public discussion. There were also appearances aimed to give information on the Bill in the Commission of Environment of the Congress of Deputies.
The transposition of the Frame Directive of Water that will be in force once its contents are incorporated to the Spanish normative, including every activity related with this resource, was initiated. A legal-technical working group of transposition and development of the Directive, in the bosom of the DGHWWQ, was created to this effect, with active collaboration of this Centre.
National Water Resources Plan. Definition of the layout of the Ebro-C.I. Catalonia-Júcar-Segura-South transfer. It is intended to maximize the use of the already existing infrastructures, such as the Cherta-Calig canal.
On the other hand, the relocation of the Secretariat of the International Association of Hydraulic Engineering and Research from Delft (Holland) to Madrid, with its present headquarters in CEDEX, deserves special mention.
In the AREA OF STUDIES AND PLANNING, once the National Water Resources Plan came into force, the works to define the layout of the water transfer Ebro-C.I. of Catalonia-Júcar-Segura-South contemplated in the Plan, commenced. A 1:10.000 and 1:25.000 scale cartography was used and a general survey of the soil made, paying special attention to the sections that may offer more difficulties. The objective of this work is to reduce to a minimum the possible environmental implications and to improve its functionality, maximizing the use of the existing infrastructures and optimizing the typology of the conduit in function of the soil characteristics.
Recommendations on pipes for pressure water transport. Maximum and admissible resistance and usual values of the safety coefficient in different materials
In the chapter of normative, the elaboration of the Recommendations on pipes for pressure water transport advanced and a group of specialists integrated by representatives of the various Administrations involved, supply companies, universities, scientific institutions, etc was created. The mentioned Recommendations will make possible to update the Set of General Technical Specifications for Water Supply Pipes of 1974, now in force.
A methodology for the assessment of the gross hydroelectrical potential by geographic information systems was developed for IBERINCO and IBERDROLA. This methodology makes possible to establish comparisons in homogeneous terms between different zones of the territory object of the study and to determine the areas of more hydroelectrical interest, that will be later the object of a more detailed analysis. The method has been applied in Guatemala, standing out its utility and advantages with respect to the systematization and handling of substantial quantities of information territorially distributed, as opposite to the traditional systems.
Within the AREA OF HYDROLOGY, in relation with the National Water Resources Plan, a study was made on the water environment of the river Ebro delta. In this work have not only been contemplated the effects of the water transfer in the delta, but the existing problems and their causes and interrelations were also considered, giving a series of actions for the hydric improvement of the delta.
The studies for the analysis and definition of different defence actions against the river Júcar floods, made in collaboration with the River Júcar Water Authority for the DGHWWQ, continued. Within these actions, the elaboration of a 1:2000 scale cartography of the flood plain and the generation of a GIS with all the information obtained, the development of a new version of the two dimensional hydraulic model GISPLANA and the gauging and validation of the model with the new cartography must be underlined.
Evaluation of the gross hydroelectric potential by Geographic Information Systems. Application to Guatemala. Drainage network calculated (GIS) and digital fluvial network
The works for the State Department of Water and Coasts of the Ministry of Environment, integrated in the agreement 'The Continental Waters in the European Union', a continuation of other work that limited the ambit of the study to the Mediterranean countries of the EU, continued their course. The works on the vulnerability of aquifers in the river Duero basin began, analysing in the first place the factors that take part in the mentioned vulnerability, that will be treated later with spatial analysis techniques based on the use of Geographic Information Systems. A new evaluation of losses in the Tajo-Segura water transfer and a study of the floods in the drainage basin of the Joaquín Costa reservoir were also made. The works for the Council of Zaragoza to evaluate the impact caused by the construction of a diversion dam in the river Ebro on the water table of the aquifer continued. In Hydrometry, the compilation of data on levels and flows in rivers, reservoirs and canals of the Basin Organisations continued, making the necessary analysis for their publication in the Gauging Yearbooks and their inclusion in the HYDRO database of the Centre. Also, the surveillance works of reservoir sediments and the updating of effective capacity curves continued.
EDAR of Logroño. Partial view. Physicochemical treatment and gasometers
In the AREA OF IRRIGATION ENGINEERING the works included in the Agreement 'Optimisation Studies for the Allocation of Water Resources in the Irrigation Zone of the Canal of Aragon and Catalonia', in the river Ebro basin, continued. Two main activities were developed under this agreement: the first one was the physical characterization of the irrigation zone, supported by 1:5000 cartography, and the compilation in situ of the information available on irrigation, which finally mounted in the GIS elaborated to that effect; the second activity was directed to the optimization of the irrigation water allocation, using remote sensing techniques as a tool to know the water demands.
The works to characterize the agrarian demand units, in order to coordinate the hydrological planning in areas with poor water resources in the basins of the rivers Guadalquivir and Júcar, concluded. The same activities are now being undertaken in the Guadalete-Barbate basin.
In the AREA OF WATER QUALITY, with regard to desalination, the activities on direction of works, technical assistance in construction, drawing-up of sets of specifications and several studies for some Administrations continued. For the DGHWWQ, the Direction of Works in the plants of Las Palmas-Telde and Santa Cruz de Tenerife was carried out and technical assistance was given to the Taibilla Canals Community in the construction of desalting plants in Cartagena and Alicante; the same will be made with the plant of Formentera, which construction has just began, besides several studies for the location of new plants in Palma de Mallorca. Technical assistance was also given to ACUSUR (Waters of the South Basin) in the works of the Carboneras (Almería) and Atabal (Málaga) plants. Works were undertaken in the plant of Almería for the Andalucian Local Government and, finally, technical assistance was given to the Council of Denia in the planning of its water supply.
The activities in waste water treatment were focussed on the implementation of functioning controls of new installations for waste water treatment made by the DGHWWQ, such as those carried out in the EDAR of Motril, Logroño or Alcázar de San Juan, among others. Special attention was also given to the validation of new technologies for the regeneration of purified waste waters using ultrafiltration polymeric membranes, being subjected to inspection several pilot plants installed in the EDAR of Barranco Seco (Las Palmas de Gran Canaria).
Going on to other matters, the limnological surveillance of eleven reservoirs in the North, Duero, Ebro, Guadiana and Tajo basins was made and the sampling in supply reservoirs of the Guadiana and Guadalquivir rivers was finished, as well as the limnological catalogues of the Duero and North basins. The vertical distribution and seasonal variation of algae during the stratification and mixing period was also studied in two reservoirs located in different climatic zones, in collaboration with the University of Salamanca. A research on the presence of cyanobacteria and their toxines in reservoirs of the Duero and North basins, made in collaboration with the Autonomous University of Madrid, began.
Experimental module of ultrafiltration. Reuse of the secondary efluent of EDAR in Barranco Seco (Las Palmas de Gran Canarias)
works for the setting-up of a surveillance and biological control network in the rivers of the Tajo and Duero basins were finished. The thematic cartography of lentic aquatic systems of the Southeast Regional Park of Madrid was carried out, using air transported remote sensing. Finally, analytic determinations for quality evaluation in the control points of the river Duero basin were made, as part of the agreement 'Studies on the Quality of Underground Waters'.
In the HYDRAULICS LABORATORY, with regard to physical models of dams, the behaviour of the spillway, outlets and intakes of the Alarcón dam was under study and the corresponding to the outlets of the tail dike of the Rialp reservoir began.
Test in a scale physical model of the Barxell channelling
In fluvial studies, the works on the channelling of the Carraixet ravine (phases II, III and IV) were completed and, within the general study on the conditioning of the Poyo, Torrente, Chiva and Pozalet ravines, the models of the high zone of the Saleta, Gallego, Horteta and Pozalet ravines and the pass of the Júcar-Turia aqueduct were finished and those in the river Barxell, in Alcoy, and the river Guadalquivir, in Córdoba, continued. The studies on the actions to be taken in extraordinary situations in reservoirs of the Duero basin and the definition and characterization of mathematical models of flood propagation in the Segura river were also completed. Works continued for the adaptation of the Joaquín Costa, Beniarres and La Tranquera dams to the normative in force, in collaboration with the Areas of Studies and Planning and Hydrology of the Centre.
In OVERSEAS ACTIVITIES, the actions in Latin America continued. Technical assistance was given to CEDEGE, Ecuador, for the execution of the complementary infrastructure works in the Peninsula of Santa Elena. Under the agreement with the Institute of Official Credit, the technical evaluation of the designs for flood control in the left bank of the river Paz, El Salvador, was carried out for the Directorate General of Commerce and Investment of the Ministry of Finance. In collaboration with the Spanish Agency of International Cooperation (AECI) and the Secretariat of Natural Resources and Environment of Honduras, the works for the assessment of the country's water balance commenced. This project arises as a continuation of a previous one that, on the same matter, was made in a simplified way on occasion of the activities related with the damages provoked by the hurricane Mitch and it will contemplate the inventory of water resources in natural regime, the identification and characterization of the water use and demands and the own water balance through cartographic modelling.
In the European context, the activities refered to the Thematic Centre of Continental Waters of the Environmental European Agency went on, and the design of EUROWATERNET (a network of information on water in Europe), in its facet of quantity, should be pointed out. The activities developed for EUROSTAT (Statistical Office of the European Commission), with regard to the modification of the questionaries for the evaluation of water resources in Europe, continued.
Visit of the students of the Swiss Federal Institute of Technology of Zurich
organisation of the presentation of the 'Dams and Development' report, made by the World Commission on Dams, the presence in the meeting of the Regional Consultative Group of the Interamerican Development Bank, celebrated in Madrid on various aspects related with the hurricane Mitch, and the participation with the AECI and the Programme of the United Nations for Development in activities related with the Central American Quinquennium (2000-2004) for the prevention of natural disasters, should be also be mentioned.
Tail weir of the Rialp reservoir
In RESEARCH AND TECHNOLOGICAL DEVELOPMENT, as part of the projects financed through the R&D&I National Plan, the project 'Construction of an Integrated Environment for the Application of Models in Real Time to Forecast Floods and Reservoir Management in the AHIS' continued and the works of the project 'Analysis of the Magnitude and Frequency of Floods and Paleofloods in the Basins of the Júcar and Segura Rivers' began, as well as those corresponding to the study of non conventional methodologies for the forecast and management of floods.
There was collaboration with the Universities of Barcelona, Vigo, Baleares, Murcia, Almería and Granada in the works of the coordinated project 'Ecological state of the Mediterranean rivers. Elaboration of an integrated index to measure the ecological state of the Mediterranean rivers. Project Guadalmed'.
In the European context, the projects 'European Energy and Water Balance Monitoring System (EWBMS)' and 'Assessment of the Regional Impact of Droughts in Europe (ARIDE)' were finished. A research project whose objective is to amplify the knowledge on vibrations in clapper gates, the use of which is increasing lately, started.
Monographic article
The National Water Resources Plan
In July 2001, after its approval by the Spanish Parliament, the Law of the National Water Resources Plan was promulgated. Just as the White Paper on Water, which first version was presented in 1998, the National Water Resources Plan has been elaborated, under the direction of the State Department of Water and Coasts of the Ministry of Environment, by the Directorate General of Hydraulic Works and Water Quality (DGHWWQ), with the collaboration, assistance and technical support of the Centro de Estudios Hidrográficos. As established by the Law of Waters, the Plan must contain, among other matters, the necessary measures to coordinate the different Water Plans of basin and the forecast and conditions of the water resources transfers between territorial ambits of the diverse Plans of basin. The material development of the Plan was compiled in five volumes of technical analysis -primarily prepared by CEDEX- and a legal text. The volumes of technical analysis correspond to the delimitation and assignment of resources in shared aquifers, analysis of the background and planned transfers, analysis of the hydraulic systems, environmental analysis and economic analysis.
Transport solutions analysed in the technical documentation of the Plan
Among the coordinating measures anticipated by the Law, the Plan sets up the delimitation and assignment of resources in the aquifers situated in territorial ambits with two or more Water Plans of basin. This measure affects to 17 hydrogeological units and entails the distribution of a volume of more than 1400 Hm3/year. As for the forecast and conditions of the transfers, the technical documentation begins with a brief presentation of some historic antecedents in matter of water transfers in Spain.
This compilation of works and projects, from the pre-Roman times to the present, reveals the solutions that have been conceived in the course of time and shows how, far from being a singularity in the context of hydraulic infrastructures, the execution of water transfers is as old as the need to have water available in zones where it is scarce. After a short journey through the historic ideas and works, the best alternatives for the solution of the problems under consideration are given.
Next, the hydrological feasibility of the possible transfers is analyzed in order to determine the strict needs of the receiving basins, the maximum amount to be transfered from the supplying ones and the technical conditions of the process.
The Plan assumes, as one of its basic principles, already pointed out in the White Paper, that no transfer of volumes destined to increase irrigation in the receiving basins will be made. Nevertheless, the attention to the increase in the supplies and the possible assignment of resources to environmental aspects are admitted. From the irrigation point of view, in relation with the environment, the transfer of resources will be solely destined to eliminate the present overexploitation of aquifers and to palliate the infra-duty and lack of guarantee of irrigation with a poor supply. A previous condition established by the Plan for possible transfers from supplying basins is the obligatory accreditation of enough flows in origin at a long term, after the maximum development predicted by the hydrological planning of the basin and the previous accomplishment of its environmental restrictions.
Recharge and pumping in the hydrogeological units studied in the Segura and South (Almería) basins
This analysis includes the possible reduction of the resources as a consequence of an hypothetical climatic change. In the same way, it is also a previous condition for possible transfers to receiving basins the obligatory accreditation of the present structural needs in the zone, after the development of internal measures for a better use of its conventional and non conventional own resources (exhaustion of the regulation possibilities of the own basin resources, reuse, joint use, savings in the urban supply networks and improvement and modernisation of the existing irrigation). As a consequence of the above, a flow net of the possible transfers under consideration, including the diverse origins of identified resources (in the Duero, Tajo, Ebro and Ródano basins, this last one in French territory), the zones in need of external inflows (in the internal basins of Catalonia, Júcar, Segura and South) and the possible transportation routes, was elaborated. These routes included the possible use of existing infrastructures, such as the Aqueduct Tajo-Segura, that makes possible nowadays the transfer of resources from the Tajo river to the Segura, Júcar and South basins.
Flow net of the possible transfers considered
The Plan undertakes later on the analysis of the environmental feasibility of the various solutions under consideration. In the first place, the possible affections in origin are revised, as a consequence of the probable derivation of flows. Special consideration deserves the Ebro delta, that was subjected to an specific analysis. In the second place, the possible affections in transport are described, studying the protected natural spaces, zones of special protection for birds (ZEPA) and humid zones with legal protection, as well as the places of natural interest communicated to the Commission of the European Union, in accordance with the Directive 92/43/CEE, relative to the conservation of natural habitats and wild fauna and flora, that could be affected by the layout of the conduits.
The objective of the analysis of the possible affected zones is to define the probable adverse impacts and the study of the potential modifications to be introduced in the layouts initially selected to reduce or, if possible, to eliminate the mentioned affections.
In the third place, the possible impacts in the areas of destination are studied, from the triple viewpoint of the water quality effects, the possible biological effects, with special attention to the migration of species, and the socio-economic impacts in the receiving areas. Once the environmental compatibility of the diverse solutions considered was studied, the economic aspects of the transfers were analysed. These included the economic optimization of the possible alternatives and their total costs and resulting prices, the cost-benefit analysis of the project, the contrast of the results obtained against the prices paid at present, the possible prices according to other origins of the water and the level of water demand than can tolerate different price levels. In short, the objective is to evaluate the economic reasoning of the different options of the transfer.
As a consequence of the above, the solution finally adopted by the Plan, in accordance with the Report issued by the National Water Council in January 2001, foresees the transfer of 1050 Hm3/year with origin in the zone of the Low Ebro of the Water Resources Plan of the Ebro basin, with destination to the territorial ambits of the Water Resources Plans of the internal basins of Catalonia (190), Júcar (315), Segura (450) and South (95). This mobilization represents something less than 1% of the renewable resources of the Spanish territory.
Ortoimagen of the Ebro delta, object of an specific analysis in the technical documentation of the Plan
The calculation hypothesis made in the above mentioned technical documentation are finally assumed in the Law of the Plan by establishing the principle of guarantee of the present and future demands of all the uses and duties of the transfering basin, included the environmental restrictions, in such a way that the development of the mentioned basin cannot be limited by the forecast of transfers, being diverse technical conditions established to this end. In the same way, with regard to the transfered waters, the Law of the Plan limits its possible destinations, so that they can only be used for the following purposes:
- To guarantee the present and future uses of the urban supply in the receiving basins, provided that a rational and efficient management of the water is applied.
- To improve the environmental conditions of those ecosystems, fluvial sections, aquifer sectors or elements of the natural water environment that are subjected at present to an intense degradation.
- To consolidate the supply of the existing irrigation duties as established in its corresponding Water Resources Plan of basin, that are in a precarious situation, both by situations of infra-duty or by lack of enough guarantee, provided that a rational and efficient management of the water is applied.
- To eliminate the present unsustainable situations, due to the existing overexploitation of the receiving basin aquifers, and to reestablish the equilibrium of the environment ensuring the subsistence of the duties linked to these aquifers.
Finally, it should be pointed out that the approval of the National Water Resources Plan made possible to complete, after long years of complicated and arduous work, the process of hydrological planning conceived and designed by the Law of Waters of 1985.