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Hand-dug wells are circular holes. about one metre (m) in diameter and 10 to 30 m in depth, dug with human labour. The wells tap water from shallow aquifers for domestic water supply, small-scale industries, and small irrigation schemes. Many hand-dug wells exist in Nigeria and in many developing countries. They are important in both urban and rural communities.The wells are dug with hoes, shovels, pickaxes and diggers. Water and cuttings are removed from the hole using a human-powered bucket-rope-pulley arrangement. Three to four men dig the well in shifts. Well construction cost is cheap, as low-scale technology and manpower are used.Problems with hand-dug wells include susceptibility to pollution/contamination; drastic declines in water level during the dry season; low well yields; silting-up of wells, and caving-in or collapsing of well walls, etc.New designs are suggested to improve the efficiency and performance of this ancient technology. In Nigeria, wells should be completed in March when the water level is deepest. Well yield is improved by using slotted concrete rings to screen the aquifer. Anti-pollution devices are also proposed for better water quality. Such wells would provide more potable water to the urban and rural poor.An improved type of slotted concrete ring has been designed for use in the screened portion of the well. N o nperforated concrete rings are used in the non-productive portions of the aquifers or above the water table, to prevent caving or collapsing of Well walls. A convex cover forms a protective rim extending beyond the circumference of the well, to prevent the entrance of surface contaminants. Water from the dug-wells IS pumped through an external filtration system into an overhead storage/treatment tank using an inexpensive pumping system.All of these designs are suggested to improve the efficiency of the wells; to provide stability to the wells and better well yield, and to lessen the incidence ofpollution/contamination within the well and its surrounding environment.