A prototype natural draft cooling tower has been designed and built on site at the El Paso solar pond. The tower's purpose is to provide cooling water to a low pressure flash evaporation unit which is producing fresh water from a brackish supply. This project was undertaken to eliminate the use of a forced draft cooling tower being used for the same purpose, thereby eliminating the parasitic fan load. The design of the tower is based on the results of a model study performed at the Mechanical and Industrial Engineering Department of The University of Texas at El Paso. The data acquired from operating this model was correlated by linear regression and a design equation was determined. This equation was then used to size the prototype tower. Preliminary testing of the prototype tower appears to confirm the validity of the model study.