A semi-circular bund (also known as a demi-lune or half-moon) is a rainwater harvesting technique consisting in digging semilunar holes in the ground with the opening perpendicular to the flow of water.[1][2]
Background
These holes are oriented against the slope of the ground, generating a small dike in the curved area with the soil from the hole itself, so they capture the rainwater running downhills.[3]