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This paper covers the unique challenges, goals, and design of the grit system for SFPUC's new 250 MGD headworks facility at their Southeast Plant (SEP). Their grit challenges stem from the configuration and operation of SFPUC's collection system. The project goals include resiliency and high level of redundancy to protect of downstream equipment in all flow scenarios. This requires targeted solutions to achieve high performance requirements within a constrained space. This paper will review the approach Carollo Engineers, Inc. used to understand SFPUC's grit issues, select the technology, and implement customized solutions to address design challenges of the new grit removal and grit handling facilities.

The original Benjamin Franklin quote, "If you fail to plan, you are planning to fail" rings true, especially in a post-covid era. In the spring of 2020, as the country shuttered its schools and businesses, water and wastewater utilities across the nation were forced to invoke their Emergency Response Plans and Continuity of Operations Plans to ensure our nation's critical infrastructure remained operational. Granted, these plans were successful and solidified the value of resiliency planning, however they also revealed a significant gap with respect to digital resiliency planning. Digital resilience relies upon enlisting technology planning and emerging digital solutions to ensure business continuity and safeguard operations. Although the traditional resiliency planning successfully ensured continued operations, most utilities were not adequately prepared for the digital requirements to send non-essential staff home to work. Telecommuting infrastructure (networks, mobile devices, etc.) was generally lacking for most utilities, and while traditional telecommuting tools are not practical for the Operations & Maintenance staff, proper digital resiliency planning can ensure sustainable and safe operation for all staff, now and well-beyond COVID. Although most frontline workers at treatment facilities have to be on-site to maintain and operate the critical infrastructure, Operators and Maintenance staff can still leverage leading-edge tools, such as Augmented Reality (AR) and knowledge management systems to safeguard quality operations and their own personal safety. This new breed of personal and portable computing technologies enables workers to view and interact with digital information in a hands-free manner. Using wearable devices, the user is delivered a first-person perspective of virtual information, such as text and images, with the surrounding physical environment to receive context-specific data and knowledge. This ultimately provides frontline workers with a first-person perspective of all relevant resources, including manuals, operating procedures, and even video, right at their fingertips.
Key Takeaways: Strengthening digital resiliency using AR yields numerous benefits to the Utility industry, including the following:
- Emergency response and quality performance
- Institutional knowledge capture and transfer
- Empowering the Next Generation of Utility experts
- Remote viewing, communication and support

Enhanced biological phosphorus removal (EBPR) is considered a potentially efficient and economical process to meet stringent phosphorus (P) discharge requirement in wastewater treatment plants (WWTPs). The success of EBPR depends on the presence of adequate organic compounds in the influent wastewater. In plants with low influent organics, addition of an external carbon source is necessary to support both denitrification and EBPR. In recent years, glycerol, has obtained great attention as a non-corrosive and economical alternative supplemental carbon source for EBPR process. Many facilities with different influent characteristics, configurations and anaerobic retention time have observed improvement in the EBPR process after glycerol addition. Although utilization of glycerol has been increased in WWTPs, the number of studies investigating its role on EBPR process is limited. The overall goal of this study is to investigate glycerol driven EBPR process and develop effective operation criteria. To achieve the objectives, a survey of full scale EBPR facilities utilizing glycerol as supplemental carbon source, batch testing and 16S rRNA gene amplicon sequencing were conducted. The effect of glycerol on phosphorus release and uptake kinetics was evaluated via full scale assessment and batch testing. Microbial composition of various glycerol acclimated sludge samples was assessed to identify a correlation between glycerol usage and the growth of different PAO groups. This study aims to propose an anaerobic metabolic model for PAOs with glycerol as the carbon source.

In California, the San Francisco (SF) Bay has become one of the most nutrient-enriched estuary in the world due to high nutrient discharges into the watershed (Cloern and Jassby, 2012). Research shows that the SF Bay has been gradually losing its resiliency to nitrogen (N) and phosphorus (P) pollution and may suffer from severe water quality impairment in the near future (Cloern et al., 2020; Novick and Senn, 2014). While wastewater discharges are considered a major contributor of nutrient point-source pollution to the environment (Drolc and Zagorc Koncan, 2002), most municipal wastewater treatment plants (WWTPs) in the SF Bay do not have biological nutrient removal (BNR) processes. In an effort to protect water quality and meet future nutrient discharge limits, 37 WWTPs in the SF Bay have participated in nutrient reduction studies led by the Bay Area Clean Water Agency (BACWA) (Falk et al., 2018). The short-term objective of these studies is to evaluate the current treatment performance and seek opportunities for total nitrogen (TN) reduction via treatment optimization or upgrading. The long-term objective is to incorporate total phosphorus (TP) reduction into the treatment process. Among these 37 WWTPs, several of them have an anaerobic selector in the secondary treatment process. Although the original intent for this design feature was filaments control, some of these facilities have reported unintended N and P removal. This provides an interesting opportunity to evaluate the technical feasibility of optimizing and/or upgrading existing systems to achieve N and P removal. However, to the best of our knowledge, no previous study has examined the carbon fractionation and microbial community compositions in these plants and their influence on nutrients reduction rate. Therefore, the objective of this study is to quantify the impact of operational parameters (e.g., retention times) and influent characteristics (i.e., COD fractions) on N and P reduction capacities in these WWTPs. This may enable us to identify facility specific features that will provide information in the nutrients removal design decision making process. Because this is an ongoing project, only operational and analytical data is presented here. Microbial community characteristics using 16S rRNA gene analysis will be performed to determine the dominant polyphosphate-accumulating organisms (PAOs), ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) communities in these systems.

Sufficient macronutrients are critical for biological wastewater treatment, especially in aerated stabilization basins (ASBs), which require continuous bacterial synthesis. However, it is not usually practical to add theoretical nutrient requirements, due to the cost of nutrients and concerns about effluent nutrient concentrations. Bioaugmentation, or the addition of viable bacteria to the system, has been observed to reduce the nutrient requirements in aerated stabilization basins. A bench-scale aerated stabilization basin study was performed to confirm the benefits of bioaugmentation. Six reactors were fed Kraft paper mill wastewater, along with high or low doses of ammonia polyphosphate blends and bioaugmentation/no bioaugmentation. Over the course of the study, all reactors that received supplemental nutrients or bioaugmentation showed better biochemical oxygen demand (BOD) removal than the control reactor, and the reactor that received high nutrient showed similar BOD removal compared to the reactor that received low nutrient and bioaugmentation.

I’m just a bill, sitting here on Capitol Hill… While almost everyone 45 years old or older knows the refrain, we rarely consider the linkage between environmental regulations that shape wastewater-treatment operations/projects and the legislated authority that Congress must create to frame that structure. Instead, questions like: “Doesn’t the United States (US) Environmental Protection Agency (EPA) understand that making all co-digestion biogas renewable identification numbers (RINs) only Advanced (or “D5”) instead of Cellulosic (or “D3”; that are worth 2 to 2.5 times the value of D5s) discourages water resource recovery facilities (WRRFs) from recovering more resources?”; or “Why doesn’t the Renewable Fuel Standard (RFS) fairly provide for electric RINs (e-RINS)?” are heard all too often. This paper is less about how Congress creates laws – and more about what happens afterwards to make federal policy and programs that deliver benefits to the public at-large and the environment.

The Fairfax County Department of Public Works and Environmental Services (DPWES) owns and operates the 67 mgd Noman Cole Jr. Pollution Control Plant (NCPCP) in Lorton, VA. The facility uses preliminary, primary, secondary and tertiary treatment to meet stringent wastewater discharge criteria for the effluent that ultimately flows into the Chesapeake Bay. DPWES is in the process of implementing $700M in capital improvement and reinvestment projects over the next 10 years. These improvements will span the entire treatment process as well as many support systems and ensure the County continues to maintain a high-quality effluent for decades to come. In 2014 Fairfax County undertook an evaluation of their disinfection process to address aging infrastructure and develop a long-term approach for resilient tertiary treatment through implementation of advanced disinfection technology, sustainable design, and alternative delivery construction. This case study provides a summary of Fairfax County's award winning Disinfection Improvements Project from design, through construction, and commissioning. It will focus on the unique aspects of the project that demonstrate Fairfax County's approach to securing a resilient future and provide valuable insight for utilities planning high-profile capital improvement projects.

As of November 2020, COVID-19 has led to more than 63 million cases and 1.47 million deaths with 270,481 of those deaths in the US. While COVID-19 commonly presents as a respiratory illness, symptomatic and asymptomatic individuals shed the COVID-causative agent (SARS-CoV-2) in their stool. This observation has motivated significant efforts to quantify SARS-CoV-2 in wastewater. The ultimate goal of these measurements is to offer an assessment of the disease prevalence within a community, which is an approach referred to as wastewater-based epidemiology. The quantification of SARS-CoV-2 in wastewater relies on concentrating and assessing the number of viral particles in wastewater using SARS-CoV-2 specific genes (nucleocapsid, N1 and N2). Recent work evaluated the performance of several concentration methods, including ultrafiltration, electronegative membranes, and polyethylene glycol (PEG) precipitation (1). The PEG method demonstrated high yield and consistent recovery. In the same study, for quantification, the SARS-CoV-2 N1 was measured at a slightly higher but significant value compared to N2. Work is ongoing to develop robust protocols for SARS-CoV-2 quantification. However, to fully realize the potential of wastewater-based epidemiology, additional methods must be developed to normalize the SARS-CoV-2 concentrations to population equivalence. It is well known that wastewater concentrations vary significantly with wet weather flow, thus a normalization technique must account for variations in wastewater strength. Wastewater concentrations under dry weather will also change with transient populations, and this is especially important for a college town or business community with commuter activity. Biomarkers can be used to determine the number of individuals contributing fecal matter to a sewershed. Ideally, biomarkers are specific to human waste, stable in wastewater, and consistently shed at known rates. This abstract reflects work to develop wastewater-based epidemiology as a tool to inform public health decisions by normalizing SARS-CoV-2 concentrations using four biomarkers. Weekly SARS-CoV-2 concentrations in influent wastewater were determined from two wastewater plants in Lawrence, KS. These concentrations have been normalized with four different biomarkers, and this SARS-CoV-2 data has been statistically correlated with COVID-19 case data. The overall purpose is to determine the most predictive metric for public health surveillance.

An increasing number of water resource recovery facilities (WRRFs) are considering options for beneficial use of biogas due to an increasing focus, both internally and externally, on resource recovery and sustainability. Conversion of biogas to electricity (through cogeneration) and to renewable natural gas (RNG) (for pipeline injection or vehicle fueling) are often considered side by side as alternatives that can produce revenue and reduce the greenhouse gas footprint of WRRFs. While there are a large number of WRRFs across the country that have operated cogeneration systems over the last decades, operating costs can vary significantly depending upon the technology selected, condition of the raw biogas, and age of the system. In addition, while the technology used to convert biogas to RNG is established, pipeline injection and vehicle fueling projects remain relatively few and far between in the U.S. These unknowns make it difficult to quantify O&M costs for utilities considering a biogas utilization project. This complicates the evaluations of these systems, since long-term operating and maintenance (O&M) costs are a significant factor in selection of a recommended alternative.