. Atlantic Watershed . Pacific Watershed
. Endorheic Basins
Argentina is a wide and diverse country with a continental areaof about 2.700.000 Km2. The great extension in latitudinal sense,which establish several climate characteristics and rain falldistribution, besides the relief diversity, bring about numerousdrainage patterns. More than one hundred basins and water surfaceregions (many of those which surpass the international boundaries),constitute the Argentina's river network .
Surface and Groundwater hydrology of Argentina has been includedinto a primary database to define the National Water ResourcesInformation System (NWRIS). Administrativeboundaries, human settlements, surface watersheds(*), rivers,lakes, dams, power developments and gauging stations were digitized.It has also been incorporated ground water regions, related withsurface rocks and aquifers type along the country.
1:2.500.000 scale maps were employed to define the main geographicaldatabase, including points, lines and polygons features. The differententities were grouped, named and renumbered according to an establishpriority system.
The NWRIS is a watershed oriented database,considering river basin boundaries as a relevant geography nearnessfor water resources and environment management.
The NWRIS is presented in ArcView 2.1 format andwill allow government offices, private institutions and plannersrelated to environmental and water resources organizations toobtain, add and integrate different source of data in Argentina'sterritory. Actually, it's linked to other database such as: WaterQuality Database, National Census & Statistical Institute,the Databook of Lakes and Reservoirs and the National MeteorologicalService.
PC ARC/INFO (1) and ARC/VIEW 2.1 (2) were the software appliedto define the NWRIS structure.
(*) It's the area of land drained by a river and it's tributaries.
The National Directorate for Water Resources Management (NDWRM)was created in 1969, then appointed within it's Ministry of Publicand Services Work, which undertook pioneer task in water resourcesplanning at federal level.
The main Directorate duties are related with:
National water policies execution
National water resources assessment and planning.
Hydrometeorology network operation
Construction and maintenance of national water public works.
Management of international water resources
International cooperation
Capacity building
As UNESCO and OMM said " No water resource management ordevelopment whether it be for the purpose of water supply forthe population, agriculture, industry or energy production, ispossible without an assessment of the quantity and quality ofwater available" (7).
In this context, the NDWRM since 1991 recognized this fact andresolved that all efforts should be undertaken at National Levelto increase technical and financial resources to strength activitiesrelated to water resources assessment, remarking the importancethat Data collect, Data processing and Data dissemination represent.
Three types of date are usually required:
I. Data on the water cycle , hydrometeorological network
II. Data on water use projects an infrastructure, water publicworks
III. Thematic Data (maps), which are utilized to interpolate networkdata to any point of the area under consideration, water balance,basin topography, DTM's, etc.
The National Water Resources Information System (NWRIS),deals with all the types of data required to follow-up the maintasks of the NDWRM.
One of the main objectives of designing a GIS is to provide theorganization and transference of knowledge to researchers andmanagers. As mentioned earlier, the original motivation for NWRISdevelopment was to facilitate the access to hydrological and watersheddata to government offices, private institutions and plannersrelated to environmental and water resources organizations toobtain, add and integrate different source of data all along thecountry.
According to this ideas, the NWRIS was organizedinto a series of branches that are described as "logical"in BR> the related bibliography.
According with what was expressed above, the data base designwas discussed and geographical features and their attributes wereidentified and codified. Two 1:2.500.000 scale maps were digitizedto define the main geographical database, while their characteristicwere procured from different sources:
a. Map of Surface Water Regions and Basins of Argentina (5)
b. Groundwater map of Argentina (6)
c. Human settlements, obtained through the National Statistical& Census Institute data base
d. Dams, power developments and gauging stations, provided bythe National Directorate for Water Resources Management
Just now, the inclusion of features numerated above, potentialthe interaction of administrative boundaries, human settlements,surface watersheds*, rivers, lakes(4), dams, power developments, gauging stations and ground waterregions related with surface rocks and aquifers type of Argentina'sterritory (3). These were grouped, named and renumbered accordingto an establish priority system.
I. Physical
I.1- Surface Hydrology
I.1.a- Administrative boundaries
I.1.b- Human Settlements .... Link to the National Statistical& Census Institute Data Base.
.... Link to the Water Quality Data Base
I.1.c. Rivers: a- Name
b- Province
c- Basin
I.1.d. Lakes: a- Name .......Link to the Databook of Lakes andReservoirs of Argentina
b- Province
c- Basin
I.1.e. Basins: a- Name
b- Province
c- Watershed
d- Administration Authority
I.2. Groundwater Hydrology:
I.2.a Main groundwater regions
I.2.b Surface rocks
I.2.c Type and characteristics of aquifers
II. Measurement Centers:
II.1 Hydro-meteorological stations:
II.1.a. Synoptic
II.1.b. Hydrometric
II.1.c. Phreatrimetric
II.1.d. Evaporimetric
II.1.e. Climatological
Each of these has been codified and differentiated, and couldbe retrieved by:
1. Identification number
It's the area of land drained by a river and it's tributaries.
b. International number
c. Name
d. Geographic coordinates (lat.-long.)
e. Province
II.2. Gauging stations:
II.2.a. Discharge:
a. Identification number
b. River
c. Location
d. Geographic coordinates (lat.-long.)
e. Elevation
f. Province
III. Hydraulic Constructions:
III.1 Dams
III.2 Power developments
III.3 Drainage buildings
III.4 Irrigation facilities
III.5 Defense buildings
Each of these has been codified and differentiate and could beretrieve by:
a. Identification number
b. Name
c. Coordinates
d. Province
e. Type of building
f. Status
PC ARC/INFO was the basic software applied to process the rawinformation. It was utilized both to digitize and add the attributesto the geographical entities belonging to the database. Once thedifferent Coverage were defined, ARCVIEW was usedto design several Views with specifics Themes,defining particular Projects.
The available combination make almost impossible to describe eachone of them. There's no limit to the number of different Viewsand Layouts related with the database contents,and this is one of the powerful reasons that justify the system.Each user decide what to retrieve, combine and display relatedto specific specialists requirements. The amount and quality ofinformation, in addition to software potentiality and flexibility,define the NWRIS effectiveness.
NWRIS was originally developed with PC ARC/INFO,but due to data and variables increment, we are now transferringto ArcInfo Workstation, both software were designed by the EnvironmentalSystem Research Institute, USA.
Because of it's complexity, water resources data analysis andland use planning demand a large amounts of detailed informationof various types, moreover, government offices often require predictionson the future status of resources and land use, applying temporal,spatial or statistical analysis for water resources management.
The purpose of this paper is to describe the experiences regardingwith the ability to arrange and transfer information within acomputer aided support system, to a countless of governments andprivate organizations, related with water resources and environmentmanagement.
Unfortunately, the results in extensive geographically orientated,besides graphics size restraint and the available combination,make almost impossible to describe and present each of them.
Figure N°1 shows the essentialelements of NWRIS, constituted by more than onehundred basins and water surface regions, which are primary divided,according to the drainage flow, in three main groups:
. Atlantic Watershed
. Pacific Watershed
. Endorheic Basins
The authors would like to thank to the authorities and institutionsthat made this study possible.
1-Environmental Systems Research Institute, 1994. PC ARC/INFO3.4.2.
2-Environmental Systems Research Institute, 1995. ARC/VIEW 2.1
3-Giraut M., Ludueña S., 1996: Cartografía HídricaSuperficial y Subterránea de la República Argentinay su integración a partir de un Sistema de InformaciónGeográfica. XVI Congreso Nacional del Agua. San Martínde los Andes. Neuquén.
4-Giraut M., Fioritti M., Ludueña S. 1997: Manejo Interactivodel Catálago de Lagos y Embalses de Argentina a partirde un Sistema de Información Geográfica. PropuestaMetodológica. Inédito.
5-INCYTH, 1986. Mapa de Cuencas y Regiones Hídricas Superficialesde la República Argentina, Escala 1:2.500.000.
6-INCYTH, 1989. Mapa Hidrogeológico de la RepúblicaArgentina, Escala 1:2.500.000
7-UNESCO-OMM, 1988. Evaluación básica de los recursoshídricos. PNUD.
April 1997, Buenos Aires, Argentina.
Miguel Angel Giraut , Marcelo Gaviño Novillo and SebastiánLudueña
Dirección Nacional de Gestión de los Recursos Hídricos
Ministerio de Economía y Obras y Servicios Públicos
Hipólito Yrigoyen N°250 Piso 11. Of 1109. C.P. 1310Buenos Aires - Argentina
e-mail: mgirau@meyosp.mecon.ar