Total Dissolved Solids Contribution to the Colorado River Associated with the Growth of Las Vegas Valley

In the past 38 years, the Las Vegas Valley (LVV) in Nevada has grown tremendously from a population of 273,288 (1970) to 1,986,146 (2008). This increase in population is coupled with exponential water demands and wastewater generation. With the growth of the valley, the salinity release from households and large hotel resorts has increased the level of TDS in the wastewater effluent, ultimately increasing the TDS in Lake Mead and Colorado River. In this research, a dynamic simulation model was developed to estimate TDS discharge into the Colorado River from the Las Vegas metropolitan area. Future per capita water uses for LVV were used to estimate future salinity discharges. The results revealed that with water conservation efforts, the TDS concentration in LVW will increase by about 14% in the year 2035. Reduction to 10% of the population using water softeners by the year 2035 will reduce TDS concentration by 126 mg/L.