Abstract: One or more water distillation chambers are provided wherein water containing salt or other impurities enters an upper inlet at a chamber and flows down a solar heated evaporative surface. The evaporative surface may be the interior of a pipe or the surface of a bottom sheet enclosed by a cover. In this way, the steam produced in the process will be constrained and be guided into a steam drum. The steam drum interior has cooling tubes whereby vapor entering the steam drum will be condensed into fresh water and collected for use. The cover may be heated to limit the amount of vapor condensing back into water before entering the steam drum. Multiple evaporation chambers and steam collection stages limit the distance water vapor must travel before entering a steam drum of a given stage, thereby minimizing the loss of water vapor through re-condensation before the vapor enters the steam drum.