In silico macro-imagineering of Salton Sea alternative futures under climate uncertainty and water transfer considerations

Abstract

The aim of the present research was to simulate the Salton Sea elevation, volume, and total dissolved solids (TDS) to assess 34 different scenarios through the year 2024 in order to better evaluate the effects of potential water management scenarios. Parameterization of an existing Salton Sea simulation model, i.e., Salton Sea Stochastic Simulation Model (S4M), was performed to account for either an increase (+), decrease (−), or no change in precipitation (Pi), evapotranspiration (Eto), and river flow volume (Ri) in the Salton Sea Basin while simultaneously implementing two different water management policies: (1) water transfers to the Salton Sea end after 2017 (based on the Quantification Settlement Agreement (QSA)) or (2) water transfers to the Salton Sea at 2017 levels continue into the future. The S4M is formulated as a compartment model based on difference equations with a daily time step using STELLA® 8.0 software. One-way analysis of variance (ANOVA) and Bonferroni multiple post hoc statistical tests were performed using IBM® SPSS® Statistics v. 22.0 with α (Type I error) = 0.05. A significant difference existed between the Baseline scenario with water transfers ending in 2017, i.e., − 241 feet above sea level (fasl) and about 69,000 ppm TDS, and the scenario with continued water transfers at 2017 levels, i.e., year 2024 end simulation of − 236.95 fasl and 61,000 ppm TDS. The results indicate that in order to improve conditions for fish and keep salinity ≤ 50,000 ppm, continued QSA water transfers cannot achieve such a result alone, ceteris paribus.