Water Supply (Sep 2021)
Estimating the future hydric needs of Baja California, Mexico. Assessment of scenarios to stop being a region with water scarcity
Abstract
This paper shows the actual conditions of freshwater availability in Baja California (BC), Mexico. It aims to estimate the water needs by 2030, and propose scenarios to move out of the scarce water region classification defined by international organizations. A population of 4.1 million people was defined for year 2030 as a target to provide at least 1,000 m3 of water per capita. As agriculture is the main water consumer in the region, empirical decomposition and optimization methods were used to define the trend line of the principal crops production and to establish the optimum conditions for planted surface reduction and water gain. The results show that by 2030, BC will need a total of 4,105 hm3 of water to be classified as a non-water scarcity region; in 2018, BC had 3,045 hm3 of renewable water per year, therefore 1,060 m3 will be needed. The best option in economic terms to attain this goal was the reduction of croplands in Mexicali with a cost of around 82 million US dollars. Although this option is the best quantitatively, the political and social implications of it are enormous; however, the correct management of the resource in critical conditions will require difficult decisions. HIGHLIGHTS In Baja California, 87% of the water supply is used in agricultural activities.; In 2017, Baja California had a water availability of 849 cubic meters per capita per year, this classifies it as a region with water scarcity.; By 2030, Baja California will need to obtain by actually unknown sources 1,060 cubic hectometres of water to be re-classified as a non-water scarcity region.; In the short-term, the installed capacity of wastewater treatment and desalination plants in Baja California will not be enough to satisfy the future water demand.; Technically speaking, the only feasible option to eliminate the water deficit is the reduction of 35,558 ha of croplands, but this action would have a huge political and social impact.;
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