Regency of West Sumba, East Nusa Tenggara Province is a developing region which has experienced watershortage for domestic use in many villages. Possibly one third of the area is considered as a karstic region, sincelimestone dominantly occupies this area. Drilled wells which exist in the area did not show significant yields, whichmay be due to karstic conditions of limestone beneath or due to marly conditions of the limestone. In karst conditionthe only water available is in solution channels of the limestone, however, to drill wells penetrate into theseunderground channels are very difficult. Only if this solution channels become underground rivers which exposed to thesurface, then, it is possible to map these routes. Finally, wells can be arranged such a way to penetrate into suchunderground rivers. Preliminary geophysical prospection using a geoelectric method at least supports a part of theseconclusions. Future water development should involve detail investigation on the karst water resources and the surfacewater resources of West Sumba.However, the available sources from karst area such as springs and underground rivershould be exploited first before the others.Partly by pumping and the rest by gravitational means.Keywords: karstic, limestone, geoelectric methodsBambang Soenarto; Peneliti Muda – Bidang Hidrologi Pusat Litbang Sumber Daya Air
