SHALLOW GROUND WATER INVESTIGATIONS IN TERAI OF NEPAL

The Terai of Nepal is the country's prime food producing region. This is a strip in the range of 25 to 45 km wide which forms the northernmost part of the Gangetic alluvial basin. The length of the strip is about 800 km, and the total area involved in the project is about 21,300 km2.

The investigations carried out by the UNDP/UNDTCD project were partly classical hydrogeological work (drilling, test pumping, water levels monitoring, etc.) and partly advanced computerized work, notably the establishment of a ground water information system (GWIS) using the United Nations Ground Water Software Series (DOS). The software for GWIS and for modeling of ground water basins was written by J. Karanjac and D. Braticevic for the UN. J. Karanjac acted in this project as a Chief Consultant in the period from June 1987 through June 1990.

The outputs of the project were the following:

• A computerized data base with about 1500 selected shallow tube wells, dug wells, and drilled wells.
• About 150 project-drilled exploration-observation-test wells.
• About 400 pumping tests.
• About ten mathematical models covering various districts within the Terai.
• Various water level maps (depth to water, absolute elevation piezometric maps, etc.)
• Reports on drilling methods in the Terai; and
• Assessment of the shallow ground water development potentials in the Terai and definition of specific exploitation criteria for different areas.