High salinity food wastes management has been a challenge because it is inhibitory to conventional biological processes such as anaerobic digestion or composting [1]. Haloferax mediterranei (HM) is a hyperhalophilic microorganism capable of producing polyhydroxyalkanoate (PHA) from wastewater with salinity in the range of 7-30% [2]. Such a high salinity environment also protects HM from culture contamination by other indigenous organisms that came with the wasted materials [3]. Moreover, the high osmotic pressure in HM cells also allow the cell wall to burst in fresh water and thus offer low energy and chemical free PHA recovery [4]. Hence, this study demonstrated an innovative pathway enabling the bioconversion of high salinity food wastes to PHA by taking advantage of HM. The outcomes of this study include: (1) confirmed the positive effect of high salinity food waste on volatile fatty acids (VFAs) production; (2) verified that unrefined VFAs can be directly used as feedstocks for high PHA productivity; (3) proved that by fresh water can be used to open the cell walls of HM for high PHA recovery without chemical addition.

Facilities throughout the United States are successfully implementing low dissolved oxygen (DO) and suboxic nutrient removal (SBNR) operations using a variety of plant configurations and controls strategies to decrease energy consumption while achieve high effluent quality standards. As part of a Department of Energy project, several facilities participated in workshops to identify common operational strategies and challenges for low DO/SBNR operational. From the workshop, it was determined that successful low DO/SBNR systems can be achieved with a variety of aeration process configurations and controls strategies. Aeration demand and blower turndown were the largest obstacles in achieving low DO operations. Instrumentation is key: understanding which probes are appropriate and the importance of probe location can significantly influence process performance. In addition, Los Angeles County Sanitation Districts is implementing SBNR operations at the Pomona Water Reclamation Plant which will provide real-world guidance on SBNR execution and operations.

With increasingly stringent effluent phosphorus requirements, the use of chemical phosphorus removal has increased. Chemical phosphorus removal in wastewater treatment has been used both as an independent/conventional process instead of biological phosphorus removal system and is nearly always included in tertiary effluent polishing to meet more stringent regulations. This interactive session at WEFTEC 2023 includes various chemicals typically used in wastewater treatment for phosphorus removal, mechanisms in chemical phosphorus removal, specifically for aluminum-based and iron-based chemical salts, dosage and mixing requirements for optimum phosphorus removal, and solids production due to chemical addition for phosphorus removal. In an interactive section, the attendees will calculate chemical dose requirements for aluminum-based and iron-based chemicals to achieve various levels of effluent phosphorus concentrations, e.g. 1 mg P/L or 0.1 mg P/L, identify the impacts of mixing on dose requirements, and estimate the sludge production. A fact sheet is scheduled for publication by the Water Environment Federation (WEF) in 2023. This interactive session is based on the work of the Chemical Phosphorus Removal, a subgroup for Phosphorus Removal Design Group, a subcommittee formed under Municipal Resource Recovery Design Committee (MRRDC) of Water Environment Federation (WEF). The goal of the Chemical Phosphorus Removal subgroup is to summarize the current knowledge in the fundamentals and provide design criteria for chemical phosphorus removal processes.

The National Alliance for Water Innovation (NAWI) is the U.S. DOE’s 5-year, $110M research Hub focused on desalination and water reuse. NAWI is organized into three Topic Areas in which projects are managed and coordinated: Materials and Manufacturing R&D (M&M), Process Innovation and Intensification R&D (PI&I), and Data, Modeling, and Analysis (DMA). In its first 3.5 years, NAWI has established the largest integrated DOE Innovation Hub (108 Research Consortium member organizations, 440 Alliance member organizations) anchored around its APRIME vision for lowering the cost and energy of desalination and water reuse. NAWI has selected 74 research projects to date, and several have reported major advances in desalination research and technology in leading scientific publications.

Technologies that leverage Artificial Intelligence (AI) and advanced data analysis have been emerging in the water industry to ensure the stability and longevity of critical infrastructure. Three case studies are presented in this paper to showcase real-world examples of how AI has been used to reduce operational costs, detect issues to optimize spending, and streamline the design of water infrastructure assets. The challenges of implementing new technologies in the water industry will also be presented, particularly when traditional practices and processes need to be maintained to ensure customer satisfaction and reliability. The technologies presented in this paper 1) significantly reduce energy consumption at the raw water pump station, 2) decrease the pipe condition auditing effort by up to 30%, optimizing renewal spending by as much as 20%, and 3) reduce the time to generate a conceptual WWTP design by up to 80% to enable alternatives analysis of innovating technologies.

This manuscript describes a full water reuse system installed to treat biodiesel wastewater. Cooking oil and grease from grease traps are waste and are transformed into clean biodiesel fuel – a resource. Wastewater treatment system includes oil and grease trap, fine screen, equalization tank, nanobubbles enhanced flotation system, Hybrid UASB anaerobic bioreactor, aerobic MBR, and optional RO. Sludge is dewatered with screw press and used as animal feed. Treated water is reused in cooling towers.

The Industrial Multi-Sector General Permit (MSGP) and its state-specific versions currently regulate stormwater discharges from specific industrial sectors as defined by their SIC/NAICS codes. Municipal Separate Storm Sewer (MS4) permits regulate MS4 agencies, typically cities and incorporated areas, and generally require that cities implement a range of Best Management Practices (BMPs), including in some cases, inspection and enforcement of discharges from commercial and industrial land uses that are not covered under an MSGP. In two U.S. Environmental Protection Agency (USEPA) regions, the regulatory approach of residual designation has been used to develop new stormwater permits specifically for Commercial, Industrial, and Institutional (CII) land uses, which require owners/operators of such properties to implement BMPs to reduce the discharge of pollutants from their properties. The first CII permit in EPA Region 9 in California is currently under development. This permit is for two watersheds Los Angeles County and will capture CII properties of 5 or more acres that are currently not covered in the California’s Industrial General Permit (IGP) and portions of properties covered under the IGP that are excluded (e.g. rooftops and parking lots). This includes the Ports of Los Angeles and Long Beach as well as a range of other CII land uses. The permit includes requirements for operators to implement BMPs, including potentially structural treatment control BMPs, to meet Water Quality Based Effluent Limits (WQBELs) that are specified for certain receiving waters within the permit. Permittees may participate in a regional stormwater capture and retention project or construct their own stormwater capture and retention system in lieu of meeting WQBELs. The permit has not yet been finalized and these conditions are subject to change.

Stormwater is managed to prevent flooding and reduce the water quality impacts of discharging stormwater to surface water. Infiltrating stormwater into the subsurface is a common stormwater management method that is effective at decreasing stormwater runoff but can transfer that stormwater to groundwater. The 2020 Supreme Court of the United States decision in the case of Hawaii Wildlife Fund et al. vs. County of Maui ruled that the functional equivalent of a point source discharge to a Water of the United States (WOTUS) are subject to regulation under the Clean Water Act (CWA). Engineered stormwater infiltration methods may be subject to regulation under the CWA if they result in functional equivalent of a direct discharge to a WOTUS. Human health and the environment will benefit as the courts side with holistic management within the water cycle.

Microvi MNE biocatalysts are polymers that contain a high concentration of bacteria specifically select for different wastewater treatment applications. The Microvi MNE biocatalysts were implemented for sidestream treatment of ammonia at OLSD in 2021 after lab- and pilot-scale testing results supported full-scale application. With an average applied ammonia load of 183 kg N/day at a 5 percent weight to volume packing density, the Microvi MNE bioreactor was able to remove an average of 128 kg ammonia-N within weeks of startup, equating to 75 – 80 percent of the design ammonia-N load. The ammonia-N removal is likely limited by the relatively dilute ammonia-N sidestream concentration of 250 – 350 mg N/L as evidenced by continuously increasing specific ammonia-N loads removed over the range of applied ammonia-N loads, suggesting that there is additional treatment capacity. The advantages of this technology include simplicity and flexibility of operation, rapid startup time, and potential footprint savings.

FHR, which is the largest refinery in Minnesota, processes not just oil, but propane, asphalt, and oil to produce transportation fuels. Such unit operations, especially during crude oil processing, generate millions of gallons of raw wastewater. The waste stream is first processed for oil and solids removal before an activated sludge process with the addition of powdered activated carbon (PAC). Due to challenges in capacity, operability, and effluent quality with the existing clarifiers, FHR decided to install MBR trains from Koch Separation Solutions (KSS) and portioned the incoming flow into two streams, with the MBR fully utilized and the remainder processed by the clarifiers. The focus of this case study is on providing an in-depth analysis of how an MBR system performs when compared to conventional clarification in this challenging environment. Effluent turbidity, total suspended solids, and membrane permeability trends are presented, along with footprint and labor comparisons.

Small community wastewater treatment plants must overcome unique challenges that larger facilities do not face. Small plants often have the same mechanical complexity and effluent standards as larger facilities, but without the benefits of stable flow/loadings, operational flexibility, easy access, and buffered protections from toxicity or industrial loadings. The Stevens Pass Sewer District (SPSD) provides a successful case study of a plant which must weather such challenges and merge a technically advanced treatment system (a 379 m3 /d [0.1 MGD] membrane system with nitrogen removal capabilities) with the unique challenges of small system dynamics. The facility reduces ammonia levels to near non-detect despite being carbon deficient, while also responding to nearly instantaneous shoulder season shifts in influent flows and loading. Staff work through extreme logistics challenges with full winter isolation, while working with residents to address the significant impacts of acute events to the plant process.

There are multiple challenges that have faced First Nations communities in effectively treating their wastewater, due to severe weather faced in Northern Canadian winters, resource constraints, or difficulties in access to equipment or expertise in maintaining and operating a wastewater treatment plant. This paper discusses how, in spite of these challenges, the use of a submerged attached growth reactor has helped meet nutrient limits in these colder climates while being simple to operate through two case studies based in different remote First Nations communities. This paper will be of interest to all community planners, consulting engineers, wastewater operators and regulators working with remote and/or small to mid-size communities in need of nutrient removal.