Water budget of the Calera Aquifer in Zacatecas, Mexico

Authors: PRADO, JOSE - Autonomous University Of Zacatecas; Garbrecht, Jurgen; Moriasi, Daniel; DAVILA, FRANCISCO - Autonomous University Of Zacatecas

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 1/18/2013
Publication Date: 10/15/2013
Citation: Prado, J.J.M., Garbrecht, J.D., Moriasi, D.N., Davila, F.M. 2013. Water budget of the Calera Aquifer in Zacatecas, Mexico. In: Mojarro Davila, F., de LeonMojarro, B., Junez Ferrera, H.E., Bautista Capetillo, C.F., editors. Agua subterranean en Zacatecas. Zacatecas, Mexico: Agua y Sociedad. p. 211-226.

Interpretive Summary: In the Calera Aquifer Region of the State of Zacatecas, Mexico, limited rainfall and low agricultural water use efficiency in combination with fast growing industrial and urban water demand are contributing to groundwater depletion at an unsustainable rate. Limited data and planning tools were available for local government and nonprofit agencies to investigate groundwater management alternatives and develop strategies for sustainable agricultural, industrial and urban groundwater utilization. An annual, watershed-scale water budget analysis was conducted to identify alternative water conservation and water use scenarios, and to determine their effectiveness at reducing groundwater extraction. The scenario analysis showed that even with a 10% reduction in industrial and urban water use and a 50% reduction in irrigation water the annual groundwater deficit remains above 10 [106 m3/yr]. The political and socio-economic impacts of such large reductions in water use are likely to be unacceptable. To achieve a 50% reduction in irrigation water use will likely involve a combination of higher irrigation efficiencies, introduction of low water-demand crops, reduction in number of existing irrigation wells, land conversions, deficit irrigation, and irrigation regulations. However, circumstantial evidence suggested that the annual irrigation water reported in the literature and used in the water budget analysis was a low estimate while groundwater recharge from rainfall was a high estimate. Thus, projected annual groundwater deficits are potentially larger than reported in this study.

Technical Abstract: In the Calera Aquifer Region of the State of Zacatecas, Mexico, limited rainfall and low agricultural water use efficiency in combination with fast growing industrial and urban water demand are contributing to groundwater depletion at an unsustainable rate. Limited data and planning tools were available for local government and nonprofit agencies to investigate groundwater management alternatives and develop strategies for sustainable agricultural, industrial and urban groundwater utilization. An annual, watershed-scale water budget analysis was conducted to identify alternative water conservation and water use scenarios, and to determine their effectiveness at reducing groundwater extraction. The scenario analysis showed that even with a 10% reduction in industrial and urban water use and a 50% reduction in irrigation water the annual groundwater deficit remains above 10 [106 m3/yr]. The political and socio-economic impacts of such large reductions in water use are likely to be unacceptable. To achieve a 50% reduction in irrigation water use will likely involve a combination of higher irrigation efficiencies, introduction of low water-demand crops, reduction in number of existing irrigation wells, land conversions, deficit irrigation, and irrigation regulations. However, circumstantial evidence suggested that the annual irrigation water reported in the literature and used in the water budget analysis was a low estimate while groundwater recharge from rainfall was a high estimate. Thus, projected annual groundwater deficits are potentially larger than reported in this study.