Abstract: The invention provides a soil irrigation solar still system of the type hng a material transparent to solar radiation, supported in a non-planar, arched or sloped roof configuration above a darkened channel containing an impure liquid in such a manner as to allow radiant energy to heat and vaporize the impure water, to provide purified water for irrigation purposes, as the result of purified water which condenses on the underside of the transparent material due to the evaporation of the impure water in the channel rolling down along the underside of the transparent material, characterized in that the channel is suspended above an excavated area in the soil, the excavated area having side wall rims spaced apart from outer edges of the channel, forming an open chamber therearound, and the roof is provided with outer edges extending beyond and terminating adjacent the respective side wall rims of the open chamber, whereby a portion of the vaporized water circulates through the space between the side wall rims an