The carbon footprint associated with water management policy options in the Las Vegas Valley, Nevada

A system dynamics model was developed to estimate the carbon dioxide (CO2) emissions associated with conveyance of water from the water source to the distribution laterals of the Las Vegas Valley. In addition, the impact of several water management policies, including water conservation, reuse, and population growth rate change was evaluated. The results show that, at present, nearly 0.53 million metric tons of CO2 emissions per year are released due to energy use for water conveyance in distribution laterals of the Valley from Lake Mead, located 32.2 km (20 miles) southeast of the Las Vegas at an elevation of nearly 366 m (1200 ft) below the Valley. The results show that the reduction in per capita water demand to 753 lpcd by 2035 can lower the CO2 emissions by approximately 16.5%. The increase in reuse of treated wastewater effluent within the valley to 77 million cubic meters by 2020 results in the decrease of CO2 emissions by 3.6%. Similarly, change in population growth rate by ±0.5% can result in CO2 emissions reduction of nearly 12.8% by 2035 when compared to the current status.