Progress on legal and practical aspects on water reuse with emphasis on drinking water – an overview

The present study highlights the evolution, the progress and the prospects of future practices of water reuse in the world. The objective was to produce a comprehensive timeline on the global evolution and progress of water reuse. This was achieved through the analysis of the state of the art on the subject. The present study is a qualitative research, where three aspects have been considered to highlight the global evolution of water reuse: i) Regulations, Standards, Criteria or Guidelines (RSCG); ii) Indirect Potable Reuse Projects (IPR); and iii) Direct Potable Reuse Projects (DPR). The study focused on both legal and practical aspects of water reuse and considered 3 timelines in the context of RSCG, IPR and DPR: 29 RSCG instruments, institutionalized from 1918 to 2020, where only 4 instruments were solely dedicated to drinking water reuse; 10 IPR projects; 5 DPR projects. To achieve good, effective results, the regulatory framework must support the objectives of a structured water reuse policy in addition to guaranteeing legitimacy and maintaining public confidence. Integrated water and wastewater management, based on technological and scientific advances, has become a relevant aspect for implementation of more adequate measures by decision makers to address future global water challenges.

Fate and persistence of antibiotic-resistant bacteria and genes through a multi-barrier treatment facility for direct potable reuse

Given the availability of technological solutions and guidelines for safe drinking water, direct potable reuse of reclaimed water has become a promising option to overcome severe lack of potable water in arid regions. However, the growing awareness of the presence of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG) in corresponding raw wastes has led to new safety concerns. This study investigated the fate of ARB and intracellular and extracellular ARG after each treatment step of an advanced water treatment facility in Windhoek, Namibia. The New Goreangab Water Reclamation Plant (NGWRP) produces drinking water from domestic secondary wastewater treatment plant effluent and directly provides for roughly a quarter of Windhoek's potable water demand. Procedures to study resistance determinants were based on both, molecular biology and culture-based microbiological methods. TaqMan real-time PCR was employed to detect and quantify intracellular resistance genes sul1, ermB, vanA, nptII and nptIII as well as extracellular resistance gene sul1. The NGWRP reduced the amount of both culturable bacterial indicators as well as the resistance genes to levels below the limit of detection in the final product. The main ozonation and the ultrafiltration had the highest removal efficiencies on both resistance determinants.

Atrazine Removal from Municipal Wastewater Using a Membrane Bioreactor

As the demand for potable water increases, direct potable reuse of wastewater is an attractive alternative method to produce potable water. However, implementation of such a process will require the removal of emerging contaminants which could accumulate in the drinking water supply. Here, the removal of atrazine, a commonly used herbicide, has been investigated. Using real and synthetic wastewater, as well as sludge from two wastewater treatment facilities in the United States in Norman, Oklahoma and Fayetteville, Arkansas, atrazine removal has been investigated. Our results indicate that about 20% of the atrazine is removed by adsorption onto the particulate matter present. Significant biodegradation of atrazine was only observed under aerobic conditions for sludge from Norman, Oklahoma. Next-generation sequencing of the activated sludge revealed the abundance of Noncardiac with known atrazine degradation pathways in the Norman aerobic sludge, which is believed to be responsible for atrazine biodegradation in our study. The detection of these bacteria could also be used to determine the likelihood of biodegradation of atrazine for a given wastewater treatment facility.

Composite toxicity assays for enhanced assessment of decentralized potable reuse systems

Decentralized direct potable reuse systems present new opportunities for resilient and sustainable facilities of the future, but potential risks must be studied carefully using advanced methods that consider potential toxicity from known and unknown oxidation byproducts.

Removal and growth of microorganisms across treatment and simulated distribution at a pilot-scale direct potable reuse facility

Multi-barrier advanced treatment trains are able to purify wastewater to drinking water standards, but improved methods are needed to better understand microbial concentrations, viability, and growth potential throughout treatment and distribution.

Toilet power: potable water reuse and the situated meaning of sustainability in the southwestern United States

<p>Proposals to recycle urban wastewater for potable purposes are at the forefront of water development. In this article I combine political ecology's attention to networked relations with Q methodology to identify the shared positions of select stakeholders in the southwestern United States, an urbanizing region increasingly reliant on potable water reuse. I employ critical Q methodology to provide a contextual understanding of how water and sanitation technology shapes subjects and environments. The analyses reveal two distinct sanitary subjectivities, which I label neosanitarian and ecosanitarian, whose views most sharply diverge regarding the appropriateness of direct potable reuse and composting toilets. The findings highlight the situated meaning of sustainability and also underscore the role that wastewater and water reuse play in shaping ecologies, which in turn, helps to identify the environments of elimination that make specific innovations in the water sector possible. In conclusion, I suggest that in the broader context of potable water reuse, the toilet is in a perniciously powerful position to make city-spaces and shape the future citizenry.</p><p><strong>Keywords</strong>: infrastructure, urban metabolism, Q methodology, water recycling, composting toilet</p>