Abstract: An impoundment for farming shrimp located in the proximity of salt and fresh water sources defined by a retaining wall defining a substantially rectangular area with a channel adjacent to the inner side of said wall and a central portion having its bottom surface above the plane of the bottom surface of the channel. One reservoir for storing salt water is located in a location of said rectangular area in close proximity to the salt water source and it also discharges the salt water contained therein into the rectangular area. Another reservoir for storing fresh water is located in the rectangular area in close proximity to the fresh water source. Another pumping assembly is used for pumping the fresh water from the fresh water source into said second reservoir means. A barrier divides the rectangular area so that two sub-areas are defined and one of the subareas being farther away from the reservoirs includes an opening of relatively small diameter.