Conjunctive management of surface and groundwater resources under projected future climate change scenarios

• Published in: Journal of hydrology (Amsterdam) Vol. 540; no. C; pp. 397 - 411
• Main Authors: Mani, Amir, Tsai, Frank T.-C., Kao, Shih-Chieh, Naz, Bibi S., Ashfaq, Moetasim, Rastogi, Deeksha
• Format: Journal Article
• Language: English
• Published: United States Elsevier B.V 01.09.2016; Elsevier
• Subjects: Aquifers; Climate Change; Conjunctive use; ENVIRONMENTAL SCIENCES; Fractional programming; Groundwater; Inflow; Management; Multi-reservoir system; Projection; Reservoirs; Runoff; Uncertainty; ASW, USA, Louisiana; Climate change; Conjunctive use; Uncertainty; Fractional programming; Multi-reservoir system; Groundwater
• ISSN: 0022-1694; 1879-2707
• DOI: 10.1016/j.jhydrol.2016.06.021

•Conjunctive use of future surface water and groundwater resources is investigated.•Climate change impacts on future inflow and conjunctive use are studied.•MILFP provides an efficient approach to optimize conflicting objectives.•Future inflows are projected from an ensemble of hydroclimate models.•Uncertainty in runoff projection is quantified via BMA. This study introduces a mixed integer linear fractional programming (MILFP) method to optimize conjunctive use of future surface water and groundwater resources under projected climate change scenarios. The conjunctive management model maximizes the ratio of groundwater usage to reservoir water usage. Future inflows to the reservoirs were estimated from the future runoffs projected through hydroclimate modeling considering the Variable Infiltration Capacity model, and 11 sets of downscaled Coupled Model Intercomparison Project phase 5 global climate model projections. Bayesian model averaging was adopted to quantify uncertainty in future runoff projections and reservoir inflow projections due to uncertain future climate projections. Optimized conjunctive management solutions were investigated for a water supply network in northern Louisiana which includes the Sparta aquifer. Runoff projections under climate change scenarios indicate that runoff will likely decrease in winter and increase in other seasons. Results from the developed conjunctive management model with MILFP indicate that the future reservoir water, even at 2.5% low inflow cumulative probability level, could counterbalance groundwater pumping reduction to satisfy demands while improving the Sparta aquifer through conditional groundwater head constraints.