ABSTRACTThe Kufra and Sarir basins of Libya have huge ground‐water resources. Three well fields–Sarir, Kufra, and Jalo–have been constructed for irrigation purposes. The Tazerbo and West Sarir well fields are under construction. Wells in these well fields have tapped only a small portion of the total ground water available. The hydrological behavior of the Sarir well field (determined by using analytical and numerical models) indicated a leaky artesian aquifer and a significant partial penetration effect. Long and short‐term pump tests did not provide true estimates of the values of transmissivity and the coefficient of storage.A steady‐state model of the Kufra and Sarir basins indicated a minimum of 80 m3/s of underflow entering from Tibesti, Chad and Sudan. A transient model was constructed to pump a total of 120 m3/s from 14 well fields. The simulation indicated that sufficient drawdown was available to last at least