Analysis of scenarios to adapt to climate change impacts in the Rio Conchos Basin

This investigation assesses some water management scenarios to adapt to and mitigate the impacts of climate change on the water resources of the Rio Conchos Basin, a main tributary of the bi-national Rio Grande Basin. The water problems in the basin are characterized by recurrent long drought periods, increasing water demands, and low efficiencies; consequently, significant deficits are experienced, not only in the water system, but also for water delivery to the US-Mexico 1944 treaty. Future climate change will exacerbate the intense competition for water resources on both sites of the border. First, an assessment was made of climate change impacts on water resources of the basin under IPCC emission scenarios A2 and A1B for the period 2040-2099. Second, simulation and analysis was done of water management scenarios that have the potential to mitigate the effects of climate change. Because a reduction in river discharge is expected, these scenarios envision an increase in groundwater use, especially in drought periods, and a decrease in water demands and an improvement in water use efficiency. Under climate change conditions, results show that reliability and resiliency of the water system will tend to decrease; consequently, the vulnerability of the system increases over the time. Furthermore, the proposed scenarios indicate some adaptation measures that could make the system more reliable and less vulnerable in meeting water demands for irrigation and municipal uses.