Working Group: Watermanagement / Waterresources
 
 

Institute: Hydroisotop GmbH,
Laboratorium zur Bestimmung von Isotopen in Umwelt und Hydrologie

Scientists:
Dr. Markus Forster
Dr. Gerold Heinrichs
Dr. Susanne Voerkelius


 

1. Project objectives

The description, evaluation and modeling of the water demand and water availability as well as water quality in the focus region of the WAVES project in Piauí (PI) and Ceará (CE) are the key issues of the working group Watermanagement / Waterresources.

Main objectives for the first six month of 1999 were to:

• continue the measurements for the water balance
• develop the groundwater model within the WARIG-Water Balance Model
• develop the local soil water model within the WARIG-Water balance Model
• intensify water quality investigations in Picos and especially in Tauá with the Brazilian counterpart
• develop scenarios (Scenario Group)
• perform a description and evaluation of water-projects in Ceará and Piauí
• develop a concept for a film about WAVES and for the "Picos information day"

2. Progress and results

2.1 Water balance / WARIG

In 1998 Hydroisotop performed the concept for the water balance model WARIG in the Picos focus area. Together with the German groups Landscape Ecology, Weihenstephan and Soil Ecology, Hohenheim and the Brazilian group of DHME, Teresina, the 6 different modules of WARIG were developed within the last 8 months. In addition to the coordination of WARIG Hydroistop is working in the modules "Monitoring", "Groundwater Modeling", "Soil Water Modeling" and "Surface Run-off Modeling".

• The "Monitoring" of the surface run-off at the Rio Guaribas during the 1999 spring, which was carried out together with the DHME, results in the best continuos data available from the area. With "quasi"-continuous measurements of precipitation, water tables and surface water flux we have now the basis for the calibration of surface, soil water and ground water models.

• The groundwater balance model within the WARIG-Project is a 2-layerd regional-scale groundwater model comprising the most important aquifer of the Guaribas-basin, the Serra Grande - aquifer and the covering mudstone layer of the Pimenteiras – aquitard. The investigation is aiming at evaluating the groundwater balance to estimate the vulnerability of the resources and the possible long-term withdrawals for future water supply. As input data for the model, the groundwater recharge was calculated via the surface runoff model and the soil water model, the flux for aquifer and aquitard was estimated from water balance calculations. Spatial distribution of hydraulic parameters has been based on hydrogeological aspects. In absence of detailed watertable measurements the calibration of the model was performed by using isotope data, especially carbon-14.
• The modeling of surface run-off and soil water balance within WARIG based on two scales. The regional modeling is made by the SCS-surface-run-off-module (Weihenstephan) and the SIMPEL-soil water-module (Weihenstephan) for the whole investigation area of about 5000 km² with soil data from the University of Hohenheim. This two large scale models are calibrated by a local modeling of surface run-off and soil water balance at eight selected representative sites using the model HILLFLOW. This local modeling is carried out by Dietrich Halm, Hohenheim, who is subcontracted for this work by Hydroisotop. The evaluation and calibration of the two models are mostly finished.

2.2. Water quality

The investigations about the water availability and quality in the region of Tauá were continued. In Tauá surface- and rainwater (cisterns) are used predominantly. The people in this region are informed officially about the effects of microbiological polluted waters and are provided with chlorine for water disinfecting. From this reason from microbiological point of view these waters mostly are impeccable. Restrictions for the use of the dam waters as drinking water are only observed at the end of the dry season. In some dams, the yearly turnover is only low. In cases of long drought or low turnover the evaporation causes high degrees of mineralisation, eutrophication and high organic content in the water.

Available groundwaters often are not suitable for use because of their high degree of mineralisation. The water scarceness of the last year resulted in program for the installation of mobile equipment for water desalinization in Ceará so that these water sources can be used for drinking water. In the region of Tauá eight desalinisators were installed by NUTEC.

2.3. Scenarios

In the frame of activities of the scenario group our subgroup developed the reference scenario under the aspects of decentralization for different regions in Piauí and Ceara (see Hyperwaves). The frame conditions for this scenario were elaborated at the "water workshop" in Kassel.

2.4 Water projects

The investigations of some "water-projects" in Piauí and Ceará were undertaken. The purpose is to get knowledge about the regional effects of this projects and deduce the most effective procedures to attain a sustainable water availability for drinking water, agricultural and industrial purposes to improve life quality. The know-how about the potentials and problems of these projects can be a contribution to optimize actual and future water-projects. The investigation of the water projects is part of expert experience that will be used for the development of scenarios for the regional development.

Up to know following projects were visited and described: Projeto de Irrigacao Baixo Acaraú, SISAR in the region of Sobral, Projeto Piloto in Vale do Gurgeia, Acude Publico Petronio Portela in Sao Raimundo Nonato, Distrito de Irrigacao do Plato de Guardalupe , Boa Esperanca, Perímetro Irrigado Várcea do Boi / Acude Favelas by Tauá. The results of a qualitative estimation of the projects are, that the success depends on the following criterions: thorough exploration, tenacity and continuity during the whole phase of realization, capacity building to train the people to be initiative and responsible by their own and at least water must be a subject to charges that enables the maintenance of the installations. Some projects show, that the benefit and economy of the investment can be intensively enhanced by a management, that takes care of the above mentioned criterions. A realization of this criterions can be found in the projects in Sobral (Ceará) and in Boa Esperanca (Piauí).

3. Partnership and cooperation

During the stay of Gerold Heinrichs (March) and Susanne Voerkelius ( April) in Brazil water-quality investigations in Tauá and Picos and water balance investigations in the region of Picos were performed with our partners of DHME and UFC. The workshop in Fortaleza and seminar in Teresina were used for presentation of results and discussions with colleagues of the WAVES project as well as with state and municipal authorities (for example DNOCS, AGESPISA).

In Fortaleza a visit to the FNS was undertaken to discuss the kind of coordination of water quality investigations and the investigations of the FNS / UECE who is working on waterborne diseases. This group starts with the evaluation of former investigations. Our subgroup in cooperation with UFC will take up a questionnaire of FNS / UECE.

Representatives of the COGERH in Fortaleza provided us with data about the dams in the region of Tauá. They showed strong interest in common future water quality investigation in the areas that are intensively used by irrigation farming. The NUTEC informed us about operation of mobile desalinization techniques and their economic efficiency.

In Fortaleza two technical talks with the director of CPRM-Ceará and president of the ABAS-Nucleo Ceará, Claudionor Carvalho de Araujo and his hydrogeolocial staff took place. In addition, a joint field trip with the CPRM specialists to the Pecém-industrial site were performed. The contact to the specialists of the CPRM was very helpful to point out the regional and technical problems of the hydrogeology in the Northeast of Brazil and gave an impression of the Brazilian projects. For the future implementation of the WAVES-results the contact to governmental institutions will be unalterable.

From the 25.06 to 24.07.1999 Mrs. Margarita López Gil from our Counterpart DHME, Teresina visited Germany. She was following an invitation of Hydroisotop and the Chair of Landscape Ecology. The main targets of this visit in Germany were information transfer, modeling the water balance in Guaribas basin and calibration of the water balance model WARIG, developed by the German WARIG group, as well as discussion of results. Mrs. Gil joint us at the WAVES-Workshop in Köln. She was mainly working at the Hydroisotop with some stays at the Chair of Landscape Ecology. There stay will results in a joint publication, which is in preparation.

Workshops in Potsdam, Fortaleza, Teresina and Köln were used to present project results about the model WARIG, water quality investigations, scenarios and the calculated water availability in the region of Picos.

Oral presentation and posters of our group are excepted at the IAH congress in September 99 in Bratisalva and at the Tropentag in October 99 Berlin. Our group submitted an extended abstract for the congress publication of the IHA.

4. Project management structure

4.1. Information day in Picos, Meeting in Teresina

We see the necessity of a better contact of the WAVES project with the local and regional governmental institutions and authority’s. Therefore we suggested a WAVES-Information-Day within the focus area and a information meeting in Teresina. Under the coordination of Hydroisotop members of different German and Brazilian working groups form the organization team.

The area around Picos is the main focus area of the WAVES-project and at the same time it is an example area of the Piauí government for future watermanagement. Therefore a meeting in Teresina is planned with representatives of the government and local authorities for information transfer. This could be a possibility for the foundation of the "Water association of the Rio Guaribas Basin- Comitê de Bacia/Agência de água de bacia", which is planned within the "Plano Estadual de Recursos Hídricos (PERH)". Some authority’s have already been contacted and there is a positive feedback on our proposal. The work in advance is performed by Hydroisotop and especially Magarita Lopez (DHME). First discussions took place in Brasilia, Bonn and Teresina.

Within the last years in the area of Picos different scientific and practical measurements were carried out from German and Brazilian scientist, often with the help of the local authorities, local co-operations and people. Therefore our working group suggested to perform an "information day" for these people. This is an approach to show the people of Picos the results and interpretations of these investigations and to give a preview of ongoing and planned studies. For the project WAVES this will be the first step for the direct and local transfer of the results. Coordinated by Hydroisotop, the organization for this information day already started and is performed by Joachim Herford (subgroup Agronomy), Inacio Barros (Agro-Ecosystem), Bettina Bach (subgroup Agroeconomy), Valdira Brito and Magarita Lopez (DHME) and Francisco Veloso (UFPí). The date for the information day is planned for November.

4.2. Film about the project WAVES

The general concept and ideas of the project WAVES are relatively unknown. Therefore our subgroup suggested the production of a WAVES-Information-Film within the frame of the BMBF/CNPq bilateral cooperation between Brazil and Germany. First discussion took place in Bonn and a preliminary film-script was developed by Hydroisotop.

5. Outlook

We will continue our field work on the investigation of hydrologic parameters in the region of Picos and the investigation on waterquality, -structure and water- management in the region of Tauá together with our Brazilian partners. For this purposes a travel to Brazil is planned in October / November.

Within WARIG the actual status permits now the simulation of future scenarios.

The development of a more detailed scenario for the focus region is planned. The organization for the "WAVES film" and the Picos information day will go on. The obtained results in the project will be presented in form of a report at the IHA congress in September in Bratislava. Together with all three German water groups there will be an oral presentation at the "Deutsche Tropentag" in Berlin in October. At the end of September the whole project WAVES will be presented at a workshop of the international bureau of the BMBF in Hannover.