Modeling the Climatological Potential for Water Conservation in Aquaculture

Abstract

Aquacultural pond management in the southern United States needs to consider water losses from infiltration beneath the pond, evaporation from the pond surface, and overflow. Sources of water to be considered are rainfall and pumped groundwater. This study examined two management methods and their effects on water conservation and groundwater pumping needs: 1) maintaining the pond full; and 2) the 6/3 management scheme, in which 7.5 cm (3 in.) of water is added when the pond level drops 15 cm (6 in.). The management schemes were applied to ponds having two infiltration rates, 0 cm/day and 0.2 cm/day. Daily pan evaporation and rainfall measurements for a 30-year period were used to simulate pond water level and pumping required to maintain pond water level for both management methods and infiltration rates. In ponds with negligible infiltration the 6/3 management method reduced average annual groundwater use by 69 cm or 68%. In ponds with 0.2 cm/day infiltration the 6/3 method reduced average annual groundwater use by 87 cm or 57%. The 6/3 method permitted greater use of rainfall while reducing groundwater pumping in aquacultural ponds with daily infiltration rates of up to 0.2 cm/day.