Evaluating the sustainability of indirect potable reuse and direct potable reuse: a southern Nevada case study

Abstract

This case study presents a framework for evaluating the sustainability of indirect potable reuse (IPR) and direct potable reuse (DPR) in Las Vegas, Nevada. A system dynamics model was developed to simulate population growth, water supply, water quality, energy costs, net present worth (NPW), and greenhouse gas (GHG) emissions. The model confirmed that DPR could achieve a net reduction in energy costs of up to US$250 million while still ensuring an adequate water supply. However, the high NPW of DPR ($1.0-$4.0 billion) relative to the status quo IPR approach ($0.6 billion) represents a significant economic hurdle, although future monetization of salt loadings and GHGs could reduce that disparity. DPR with ozone-biofiltration would also be hindered by an estimated concentration of total dissolved solids of up to 1,300 mg/L. Despite these barriers to implementation in Las Vegas, certain site-specific conditions may make DPR more attractive in other locations. K E Y W O R D S direct potable reuse, indirect potable reuse, net present worth, sustainability, system dynamics, water supply

The Impact of Advanced Treatment Technologies on the Energy Use in Satellite Water Reuse Plants

“…Water reclamation has been practiced in the form of wastewater treatment plants (WWTP) using centralized treatment facilities located at low elevations to allow gravity collection of wastewater from metropolitan areas. In the United States, applications of water reuse in order of descending water volumes are agricultural irrigation, industrial recycling and reuse, landscape irrigation, groundwater recharge, recreational and environmental uses, nonpotable urban uses, and potable reuse [11,12]. Internationally, with few exceptions, water reuse is being practiced in a similar fashion as in the United States, including in China [13], Japan [14,15], Europe [16,17], and Africa [18].…”

Design Aspects, Energy Consumption Evaluation, and Offset for Drinking Water Treatment Operation

“…Energy conservation and sustainability is one of the pressing issues being faced by the water industry today as drinking water treatment and wastewater treatment are highly energy-intensive processes [1]. These processes account for about 2% of the United States' total energy use, resulting in the emissions of about 45 million tons of greenhouse gases (GHG) [2].…”

Online monitoring of bromate in treated wastewater: implications for potable water reuse

“…7,8 Therefore, controlling bromate ion formation is a significant challenge for AWTPs without an RO membrane treatment process, which has gained attention as an alternative of RO-based AWTP for potable reuse in inland locations. [9][10][11] Online monitoring of bromate ion concentrations after ozonation can help improve the safety of recycled water, which will aid the implementation of countermeasures such as reduction of ozone doses up to the guideline-prescribed values. However, the bromate ion concentrations in partsper-billion (μg L −1 ) are analyzed using laboratory-based analytical techniques such as ion chromatography coupled with suppressed conductivity followed by a post-column reaction 12,13 and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS).…”

“…7,8 Therefore, controlling bromate ion formation is a significant challenge for AWTPs without an RO membrane treatment process, which has gained attention as an alternative of RO-based AWTP for potable reuse in inland locations. 9–11…”