Charco dams are a traditional means of water harvesting in arid and semi-arid landscapes of Eastern Africa, especially in Tanzania. This type of dam has a deep reservoir and limited surface area which helps to reduce water-loss from evaporation. Charco dams are built to collect rainwater and runoff water from flat surfaces. As a result, they are suitable for livestock watering and crop irrigation, but less suitable for domestic use (unless the water is treated). Typically, trees and shrubs are planted around the edges of the dam to act as windbreaks to further reduce evaporation. Small earth dams may vary significantly in size based on the water storage capacity needed. Storage of up to 1000m3 is possible, beyond which a pond is considered large and will require different building protocols. Dams need to be thoroughly planned in order to ensure their feasibility, longevity, and safety. Please make sure to consult the additional supporting resources provided for more specific details on how to plan and build a Charco dam, or talk to a local extension officer for help on planning and implementing a Charco dam in your landscape.