Wells were first constructed at least eight thousand years ago .
Wells were first historically vary in construction from a simple scoop in the sediment of a dry watercourse to the stepwells of India , the qanats of Iran , and the shadoofs and sakiehs of India .
Wells were first constructed at least eight thousand years ago and historically vary in construction from a simple scoop in the sediment of a dry watercourse to the stepwells of India , the qanats of Iran , and the shadoofs and sakiehs of India .