Triple bottom line costs for multiple potable reuse treatment schemes

Abstract

As populations around the world continue to grow and communities appreciate the difficulty in securing new water supplies, water reuse is expected to expand in the coming years. Other factors, such as localized drought severity and increased community and regulatory pressure may also increase the application of water reuse. The level of treatment provided in water reuse projects varies significantly throughout the world depending on numerous factors, such as regulations, water quality, end uses of the treated water, and public influence. Selecting the appropriate treatment technology and level of treatment can be a complex decision. Recent experiences within the water reuse industry have demonstrated that governmental and nongovernmental organizations and advocacy groups can influence selection of a higher or more costly level of treatment than is fit for the water purpose. This is partially because of a failure to consider the full financial, environmental, and social elements of the triple bottom line (TBL). The focus of this report was to develop and apply a TBL framework to help guide sound selection of the treatment process. The objective is to match the treatment to the intended use without expending unnecessary funds or energy or emitting excess greenhouse gas (GHG) and other air emissions, while minimizing other environmental and social costs. Although the present research addresses water reuse only, the TBL approach is equally applicable toward evaluating the full suite of water supply and demand alternatives.Environ. Sci.: Water Res. Technol. This journal is More communities than ever are investigating the feasibility of implementing potable reuse projects to increase their water supply and protect against periods of drought. The complexity of this task is compounded by the variety of reuse treatment technologies, which can differ in terms of benefit to the end user as well as in the true cost of implementation. This paper examines the benefits and costs of various levels of treatment for potable reuse applications. A triple bottom line (TBL) analysis was performed that includes financial, environmental, and social elements to help ensure that the right treatment process is applied for the intended use without expending unnecessary funds, energy, greenhouse gases, and other social and environmental costs.

Viral Surrogates in Potable Reuse Applications: Evaluation of a Membrane Bioreactor and Full Advanced Treatment

“…From a design perspective, discrepancies between observed versus regulatory LRVs can result in overly conservative and potentially unsustainable treatment train designs (Schimmoller et al 2015). Therefore, the water reuse industry is now considering virus LRVs for membrane-based processes, particularly for MBRs, and to identify rapid methods for validating process integrity and performance.…”

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

“…The unit cost curves in Plumlee et al () were actually based on 2011 U.S. dollars. The estimated costs were first adjusted to 2015 U.S. dollars using the relevant construction cost index (ENR, ), and further adjustments for the time value of money were based on a discount rate of 3% for consistency with Schimmoller et al (). Similar adjustments were made for the Nevada Groundwater Development Project and the DPR pipeline.…”

“…When considering various water supply alternatives, the evaluation and optimization of life cycle cost can be invaluable to the decision‐making process (Bradshaw, Ashoori, Osorio, & Luthy, ). A more comprehensive triple bottom line analysis might even be warranted because of its ability to simultaneously consider the social, environmental, and economic implications of an engineering design (Haak, Sundaram, & Pagilla, ; Schimmoller, Kealy, & Foster, ; Schoen et al, ). With respect to social considerations, the recent literature demonstrates that, when designed and operated properly, potable reuse systems provide adequate protection of public health (Amoueyan, Ahmad, Eisenberg, & Gerrity, ; Amoueyan, Ahmad, Eisenberg, Pecson, & Gerrity, ; Chaudhry, Hamilton, Haas, & Nelson, ; Pecson et al, ; Pecson, Trussell, Pisarenko, & Trussell, ; Soller, Eftim, Warren, & Nappier, ).…”

“…With respect to social considerations, the recent literature demonstrates that, when designed and operated properly, potable reuse systems provide adequate protection of public health (Amoueyan, Ahmad, Eisenberg, & Gerrity, ; Amoueyan, Ahmad, Eisenberg, Pecson, & Gerrity, ; Chaudhry, Hamilton, Haas, & Nelson, ; Pecson et al, ; Pecson, Trussell, Pisarenko, & Trussell, ; Soller, Eftim, Warren, & Nappier, ). Particularly in California, potable reuse treatment trains often use both low‐pressure and high‐pressure (i.e., reverse osmosis [RO]) membranes, but when not mandated by local regulations or necessitated by salinity management, the use of membranes may lead to excessive costs or overall sustainability concerns (Bradshaw et al, ; Schimmoller et al, ). Alternative treatment trains using ozone (O 3 )‐biofiltration have been identified as “equivalent” on the basis of public health (Trussell, Salveson, Snyder, Trussell, & Gerrity, ) and are more cost and energy efficient (Gerrity et al, ; Herman, Scruggs, & Thomson, ), but these benefits must be evaluated against certain water quality limitations, including higher concentrations of total organic carbon (TOC) and total dissolved solids (TDS) in the final product water.…”

Water reuse versus water conveyance for supply augmentation: Cost and carbon footprint

“…A similar contrast was found regarding greenhouse gases and other air emissions, with RO‐based schemes using more energy and thus having a greater environmental impact under these two metrics. The net present value of all TBL costs combined was the lowest for the GAC‐based treatment (Schimmoller et al, ).…”