Conference Papers

W-SPHERE (Wastewater - SARS Public Health Environmental Response) as Global Data Center for SARS-CoV-2 detection in wastewater and environmental samples Andri T Rachmadi*, MSU, Postdoc, rachmad1@msu.edu. Collleen Naughton, UC Merceed, Asst Professor. Gertjan Medema, KWR, Lead researcher. Panagis Katsivelis, Ventic IT, Lead technician, and Joan B. Rose, MSU, Professor. Over a year since the declaration of the global coronavirus disease 2019 (COVID-19) pandemic there have been over 219 million cases and 4.55 million deaths recorded. Wastewater-based epidemiology (WBE) quickly adapted their existing methods to detect SARS-CoV-2 RNA in wastewater to track community spread of the virus. Wastewater surveillance has the potential to provide a real-time view of trends in community infection while public health struggles to monitor individuals and obtain good data to support testing, interventions (closures, masks, social distancing) and economic reopening policy decisions. The wastewater surveillance can also support vaccination implementation and tracking of variants of concern. Unlike COVID-19 case and mortality data, there was not a global dashboard to track wastewater monitoring of SARS-CoV-2 RNA worldwide. Currently, over 2600+ sites including cities and counties (regional systems) across the world are monitoring wastewater for SARS-CoV-2 or have communicated that they will be setting up for monitoring soon. Using COVIDPoops19 as a starting point the W-SPHERE datasets, along with their metadata and dictionaries, will be open for access and sharing across the globe in a number of reusable formats. The mission of W-SPHERE is to advance environmental surveillance of sewage to inform local and global efforts for monitoring and supporting public health measures to combat COVID-19. We use ArcGIS online dashboards for data visualization, case studies, and employ geospatial and statistical tools for data normalization standardization, comparison, and analysis. Methods for the W-SPHERE online dashboard included direct data extraction from available online dashboard worldwide, data from individual or team contributors, and input from SARS-CoV-2 environmental surveillance working groups from low and middle income countries. All the input parameters were uploaded into our standardized data form. The data form contains dashboard meta data, site detailed information, laboratory methods for SARS-CoV-2 detection, and sample details such as gene targets measured, collection method, SARS-CoV-2 concentrations, presence absence, limit of detection, and concentration unit. On the W-SPHERE dashboard, the user will have the option to select public health use cases based on specific characteristics such as the system setting (e.g. sewered, non-sewered system) or use case type (e.g. city level, national level, buildings, hospitals, etc.). The story map will provide a closer look at the different steps (e.g. design, monitoring, and execution) for developing a program that used the wastewater data for public health decision making. After a year of data tracking, wastewater surveillance for SARS-CoV-2 is conducted in over 53 countries, 2,082 sites, with 248 universities/institutions involved. A small subset (75) of those monitoring for SARS-CoV-2 in wastewater provide their data publicly and only thirteen provide limited downloadable data. Of the 53 that are conducting wastewater monitoring: 35 (65%) are in high-income countries, 11 (20%) are upper middle income, 8 (15%) are lower middle income, and 0% are low-income countries. Currently, W-SPHERE has 13 datasets available from 8 different countries consist of 528 sites and more than 20,000 samples. More datasets are being added weekly. Sites included sewage from wastewater treatment facility, sewer shed from building (eg. social service, correctional facilities) and environmental samples (impacted rivers). Of the13 datasets, 12 reported the detection SARS-CoV-2 using N1, N2 genes or both and only one dataset used the E gene (US-Honolulu). In the standardized datasets, information such as presence absence results and population served by the wastewater treatment are included. In addition, SARS-CoV-2 concentration trends (increase, slight increase, decrease, or no change) from a selectable time period are available. The trend was calculated by using linear regression with the five most recent measurements. As an open access dashboard, all the data are available for to download in csv format. As examples of the datasets from May to July 2021, 3 correctional facilities in New Mexico showed an increase trend of SARS-CoV-2 concentrations in their sewage, which was also observed at three Switzerland WWTPs which served more than 50 thousand populations and Ohio WWTPs which served more than 300 thousand people. There was a statistical difference between SARS-CoV-2 concentrations among the three datasets however representing the different populations served and likely number of infections in the last 6 months of sampling (January-June 2021), Kruskal-Wallis test (P<0.001, =0.05). Compelling case studies of wastewater surveillance for SARS-CoV-2 and uses in public health have been included. The Catalan surveillance network of SARS-CoV-2 is monitoring SARS-CoV-2 weekly from 56 WWTPs and used the information for i. estimated circulation of SARS-CoV-2 in communities where clinical testing is far from optimal or less available, ii. assessment of the efficacy of containment measures implemented by Health authorities in different areas of the Catalan territory and iii. identification of potential outbreaks in monitored municipalities (forecasting of clinical cases, i.e., early-warning). Another example from the Dutch demonstrated that the trends of the virus served an indicator of undertesting in city areas and early warning and localization of resurgence. Wastewater surveillance has been a powerful tool for providing information that helped to build resilience to the COVID-19 pandemic. However, there is a severe lack of data in low-income countries, limited data sharing publicly and challenges in analysis of the data to communicate to public health officials for decision making.

INTRODUCTION The Town of Cary, NC Utilities Department serves a population of roughly 175,000. Cary is a regional leader in sustainability and climate change mitigation with an ambitious goal of reducing town wide GHG emissions by 25 percent by 2025 and by 100 percent by 2040. A high-level study conducted in 2011 showed water and wastewater services account for approximately 60 percent of Cary's municipal GHG emissions. More recently, in conjunction with GHG emission accounting research led by the Stantec Institute for Water Technology and Policy, Cary developed a comprehensive emissions inventory for their three water reclamation facilities (WRF), one water treatment facility (WTF), and one major pump station to both measure progress related to emission reduction activities and to incorporate GHG impact analyses in alternative selection processes. One of the WRFs included in the inventory is the 18 million gallon per day (MGD) Western Wake Regional Water Reclamation Facility (WWRWRF), commissioned in 2014 and discharging to the Cape Fear River. The WWRWRF solids handling facility includes belt filter press thickening of waste activated sludge (WAS) and thermal drying via two BioCon dryers with a combined capacity of 1,489 wet pounds per hour. The dried biosolids are processed through a pelletizer and distributed as a Class A product for land application. The facility's original design included an energy recovery system (ERS) that would combust dried biosolids to generate heat for the drying process, thereby offsetting natural gas consumption. The ERS was removed from the design with the intent to revisit installation in the future. In October 2022, Cary commissioned Stantec to assess the GHG emissions impact of installing an ERS using the newly developed GHG inventory tool. The purpose of this paper is to provide an overview of Cary's GHG emission inventory tool, understand is applicability for utilities of all sizes and treatment technologies, present the results of the GHG emission impact analysis and provide considerations for incorporating GHG evaluations in facility planning and alternative selection processes. METHODOLOGY Cary's GHG was developed for a baseline year of 2021 and is an Excel-based calculator specifically focused on water and wastewater facility emissions. The calculator sources reference data and equations from the Local Government Operations Protocol, IPCC Guidelines, EPA GHG Emission Factors Hub, EPA Waste Reduction Model, and the Biosolids Emissions Assessment Model (BEAM). The tool was developed with a user-friendly interface and can be quickly updated annually to monitor emissions over time or applied as a decision-making tool by comparing capital improvement or operational optimization alternatives. Energy recovery systems accept and combust dried biosolids from a dryer and recover the waste heat from the combustion process for dryer operation. The end product is ash, which can either be disposed via a landfill or beneficially reused as a construction material amendment. The heat produced by the ERS offsets the natural gas required to heat the dryer. WWRWRF's 2021 GHG inventory was used to assess the theoretical GHG impact of installing an ERS. Installation of an ERS is anticipated to impact GHG emissions in five areas: 1.Reduced natural gas combustion by the dryer 2.Reduced GHG offset from biosolid land application 3.Reduced end-product hauling 4.Increased electricity consumption from ERS equipment motors 5.Increased direct emissions from combustion processes There are several energy recovery technologies available to WRFs. However, this evaluation assumed the Veolia ERS system would be installed as it is designed to integrate with the BioCon dryers already in operation at the WWRWRF. The design criteria assumed a throughput of 1,489 lb/hr, consistent with the existing dryer system nameplate capacity and energy consumption estimates were provided for the full system capacity and are summarized in Table 1. The GHG impact from the ERS was assessed for 2021 only and during that year the WWRWRF dryer throughput averaged 636 lb/hr. Electricity consumed by the ERS system was estimated by multiplying the expected energy draw at design capacity by the ratio of the actual and design loads. The ash production rate is approximately 40 percent of 2021 dried biosolids production rate and the average hauled distance for ash disposal was assumed to be 30 percent of that of biosolids land application. Based on Veolia-reported values, the ERS is assumed to provide 68 percent of the dryer's heat demand and the remaining is provided by natural gas combustion. While the ERS does require some consumables for flue gas treatment such as urea, emissions associated with its transport were not included as consumption is estimated at less than one tote per year. In addition, no changes in facility or administrative costs were assumed. There is not current guidance on GHG emission estimates from an ERS. Therefore, solids combustion emissions were calculated using the 'Combustion' tab in BEAM, which is specifically intended for solids incinerators. BEAM calculates Scope 1 emissions from solids combustion as well as the biogenic CO ‚‚ emissions that arise from the conversion of the organic matter in the solids to CO ‚‚. Per LGOP and IPCC guidance, biogenic emissions can be estimated and monitored but do not need to be included in a facility's inventory. RESULTS Results of the analysis are presented in Table 2 and Figure 1 and show the existing and theoretical (with ERS) emissions in 2021. The results of this analysis show that installation and operation of the ERS system would have increased 2021 solids handling related GHG emissions by 36 percent. Nearly all of the ERS combustion emissions are as nitrous oxide, which is particularly difficult to estimate, with significant variability in emission factors. As such, actual emissions may vary based on how well the energy recovery system is maintained and operated. The difference in GHG emissions is also heavily influenced by the elimination of land application practices, which currently provide Cary with a significant emission offset. This is demonstrated in Figure 1, which shows there would not be any 'negative' emissions without land application practices. As previously mentioned, Cary may beneficially reuse the ash product for construction materials, but this practice is not expected to provide the same magnitude of offset since it does not directly increase carbon sequestered biomass. While a more complete evaluation of all financial, environmental, and social impacts of the technology alternative is recommended, this work demonstrated Cary's ability to quickly and effectively quantify the GHG emission impact of a technology alternative. In addition, this evaluation revealed the tradeoffs within the circular economy as an alternative intended to reduce reliance on fossil fuels may result in reduced production of value beneficially reused biosolids.

The design and implementation of stormwater best management practices (BMPs) is based on regulations and guidance that tries to anticipate and model the impacts of each system. The deployment of in-situ sensors along with stormwater BMPs has allowed communities to more accurately understand BMP performance before, during, and after rain events. This has led to a more accurate accounting of BMP performance and reduced costs by municipalities in complying with their MS4 permits and TMDL compliance goals. Our research has specifically focused on documenting the performance of permeable pavement systems, which are often governed in their implementation by the soil on which they are installed. The permeable pavement system chosen for this work is PaveDrain, a system comprised of permeable articulating concrete blocks (P-ACBs). P-ACB systems differ from traditional permeable pavers because they have 1) open joints and 2) are able to handle heavy traffic loads. The open joints means this system handles more rain water, and is easier to maintain (cleaning process is required less frequently and is easier to perform). The suitability to handle heavy traffic loads means that PaveDrain can be used in additional applications like roadways, traffic aisles, and truck stops. For this work, the following sites were studied: Table 1. Studied Sites The sensor system monitors water level in the stone base, with a nearby weather station monitoring rainfall, temperature, barometric pressure and relative humidity. As can be seen in the figures below, water enters the base quickly during rainfall events, and over time exfiltrates from the stone base into the soil [where present, the height of internal drainage structures is notated]. Figure 1 Measured rainfall and water level with corresponding subgrade infiltration rates. In both sites, most runoff draining into the BMP has exfiltrated into the soil, reentering the natural water cycle in a decentralized fashion within 24 hours of the end of a rainfall event. Instantaneous rates of exfiltration with high hydrostatic head pressure reached close to 1.00 in/hr. Average rates of exfiltration over the first 48 hours are 0.40 in/hr0.50 in/hr. For most jurisdictions stormwater designs would expect clay soil to infiltrate at 0.04 in/hr, a full order of magnitude less than the rates being measured in the field. The discrepancy between observed and expected values is attributable to the heterogenous nature of soil. While clay soil is present, so are more permeable soils which form 3-dimensional networks and paths for water to exit the BMP system leading to significantly elevated performance. Furthermore, based upon these values, modeling was done to understand the value of TSS and TP removal beyond what is typically credited to a permeable pavement system. Source loading and management modeling software (WinSLAMM) was used to reevaluate the installed system in Cudahy, utilizing site-specific parameters including measured subgrade infiltration rate and product-specific performance properties representative of the P-ACB system (PaveDrain) [Figure 2]. It was determined that pollutant removal costs required to close compliance gaps can be reduced by a factor of 12 when modeling implements measured data and parameter definitions that reflect system capabilities. [Table 2] Figure 2. Subgrade sediment accumulation impact on pollutant removal. Table 2. Economic impact of SLAMM enhancement and in-situ sensor system. In communities that have high percentages of impermeable cover (e.g., urban cores), the use of low-maintenance, high-performing BMPs like P-ACBs, would allow all communities to more effectively address stormwater challenges, especially in the face of more extreme rainfall events.

Introduction In general, the two options for biosolids incineration are multiple hearth furnaces and FBI units. In the 1970s, tighter emission regulations were introduced, which encouraged the replacement of multiple hearth furnaces with fluidized bed incinerators. Veolia Water Technologies & Solutions (Veolia) is an established industry leader in high temperature fluidized bed (HTFB) incineration, also known as fluidized bed incineration (FBI). Over the years, Veolia has replaced several multiple hearth furnaces (MHF) with specialized FBI units. These include: Ypsilanti (1 MHF replaced with 1 FBI), TZ Osborne Greensboro (1 MHF replaced with 1 FBI), Green Bay (2 MHF replaced with 1 FBI), Mill Creek (6 MHF replaced with 3 FBI), Southerly (4 MHF replaced with 3 FBI), and Sutton (3 MHF replaced with 3 FBI). Emerging PFAS air and solids regulations have impacted the process design of FBI systems. This presentation will review: - Drivers of multiple hearth replacement by fluidized bed incinerators - The greenhouse gas emissions quantification of a current fluidized bed incinerator and associated air pollution control compared to that of a multiple hearth furnace - Impacts of PFAS regulations on process design of FBI systems Why are Multiple Hearth Furnaces Being Replaced by Fluidized Bed Incinerators? Multiple hearth furnaces (MHF) are circular steel units with multiple hearths (shelves) where biosolids are fed. The solids are raked towards the center of the hearth where the combustion air rises. Biosolids burn in the MHF at a range of 572-1796oF (Vallero, 2008). Biosolids fall through holes in the hearths where they drop to the hearth below, until they reach the bottom of the furnace (as ash), where it is removed (United States Environmental Protection Agency, 2003). Veolia provides a teardrop shaped fluidized bed incinerator, where biosolids are fed directly into or above a fluidized sand bed. The bed is fluidized via preheated air that is injected into a windbox, which then forces the air through tuyeres that are embedded in a refractory arch dome. The tuyeres evenly distributes the combustion air through the sand bed to ensure homogenous temperature throughout the bed. Veolia FBI reactors are operated with a freeboard temperature of ~1550oF. The emissions regulation that prompted the replacement of MHF with FBIs was the Clean Air Act of 1970. Two distinct advantages that FBIs have over MHF are that there is significantly less excess air required (40% versus 75-100%, respectively) and the ability to operate autogenously (United States Environmental Protection Agency, 2003) (Winchell, et al., 2021). Greenhouse Gas Emissions Impacts on Replacements of MHF with FBIs Veolia has developed a methodology to quantify greenhouse gas emissions, utilizing ISO 14064-2 as a guide and applied it on multiple projects, including that of fluidized bed incinerators. Initially, a base case and a project case are determined. For the purposes of this presentation, the base case is a multiple hearth furnace application, and the project case is a fluidized bed incinerator application. Water, electricity, natural gas/fuel, and chemical consumption are all taken into consideration. Using emissions factors to convert these values into tonnes of CO2 equivalents per year, we can quantify the GHG impacts of a MHF replacement with an FBI. This quantification is ongoing, but results will be presented if this abstract is selected. The results of these quantifications can be used to justify selecting one unit process over another, such as choosing a granular activated carbon unit over a sorbent polymer composite unit. PFAS Regulation Impact on FBI Process Design Similar to regulations influencing multiple hearth replacements in the 1970s, emerging PFAS regulations will also influence what unit processes will be used in incinerator systems. Currently, there is limited published data on the PFAS treatment ability of a high temperature fluidized bed incinerator. There are air pollution control unit processes however, used in FBI systems that have proven effectiveness on the treatment of PFAS compounds. In the United States, if the incineration system is new, it must be designed to meet MACT LLLL requirements, which includes the removal of mercury, dioxins, furans, cadmium, lead, NOx, SO2, HCl, and particulate matter (Figure 1). The main addition in a MACT LLLL system is a granular activated carbon (GAC) unit. In drinking water applications, the use of a GAC unit for PFAS treatment is common (Winchell, et al., 2021). Using a GAC unit, PFAS treatment efficiencies can exceed 99% in water streams (Barr Engineering Co., Hazen and Sawyer, 2023). It is important to note that the efficiency of PFAS treatment using a GAC unit is dependent on the chain length and the presence of competitors (total organic carbon, volatile organic compounds) (Barr Engineering Co., Hazen and Sawyer, 2023). There is proven ability to treat PFAS in water streams using GAC units, but limited data available for the treatment in gas streams. However, there is much data on the removal of acid gases (PFAS thermally converts to hydrogen fluoride (HF)) using wet scrubbers, which are used on almost all our incinerator trains (Wang, et al., 2022). If the incinerator system is existing and a furnace replacement or retrofit is being performed, the system must be designed to meet MACT MMMM requirements (Figure 2). In this system, instead of a GAC unit, a sorbent polymer composite system (SPC) is used for mercury removal. However, the PFAS treatment ability of SPC units has not yet been studied (Barr Engineering Co., Hazen and Sawyer, 2023). Summary Multiple hearth furnaces have been replacing by fluidized bed incinerators since the early 1970s, however, the greenhouse gas emissions impacts have not been measured. Using Veolia methodology, we can quantify the impacts of these replacements, while also identifying areas where emissions could potentially be reduced (for example, selecting certain air pollution control unit processes over another). Depending on if the fluidized bed incinerator is replacing a MHF or is part of a brand new plant, the air pollution control equipment may be different. This may also impact the PFAS treatment ability of the system, as GAC units have been proven to treat PFAS, whereas SPC units have yet to be studied. It is imperative that studies be conducted to analyze not only flue gas PFAS concentration (before and after air pollution control units), but to treat PFAS-laden ash slurry as well.

Drinking water, wastewater, and stormwater (water sector) utilities are experiencing more costly operational and financial impacts from the increased frequency and severity of climate change-related disasters. As a result, the financial and insurance industries are increasing their focus on climate change risk in their assessments of water sector utilities. Thus, it is important that water sector utilities properly identify, manage, and disclose climate change risk and resiliency efforts not only to ensure that they can continue to reliably and effectively provide essential water services, but also because doing so can influence the utilities' credit ratings, investor relations, and ability to attract investors and access insurance coverage at an affordable price. In 2022, the U.S. Environmental Protection Agency's Creating Resilient Water Utilities (CRWU) initiative convened a Financial Working Group comprised of subject matter experts from the financial and insurance industries, academia, and water sector utility managers to address this topic. The Workgroup participated in a series of virtual and in-person meetings from June 2022 through January 2023. The Workgroup recognized that water sector utilities that effectively identify, manage, and disclose climate change risk and resiliency efforts in a responsible manner are more highly rated, broaden the investor base, improve insurance access and pricing, and gain more support from ratepayers. The Workgroup further discussed three main topics: 1) data to identify climate change threats at water sector utilities; 2) methods and practices to identify and assess climate change risks; and 3) effective outreach and disclosure practices to manage these risks. This session will include a presentation of the working group's process, findings, and continued work along with an interactive panel discussion including key working group members. The panel will highlight the varying sector perspectives and discuss commonalities and areas for the sectors to better collaborate. An audience-driven question and answer session will follow the presentation and panel discussion.

Several countries in the Middle East have experienced accelerated growth since the mid-1970's when their current sewerage systems were designed. The Abu Dhabi Sewerage Services Company (ADSSC) is the service provider for sewerage services throughout the Emirate of Abu Dhabi. Many of its existing sewerage infrastructure assets were overloaded and reaching the end of their intended life. ADSSC embarked on a major capital improvement program (CIP). One of the key components of the CIP was the construction of a deep tunnel which includes approximately 40 kilometers (km), 25 miles of deep tunnel sewer (with internal diameters of 4.0, 5.0 and 5.5 meters; which equal 13, 16 and 18 feet, respectively), as well as over 50 km (30 miles) of micro-tunnelled link sewers, a large new main tunnel pumping station at the downstream end of the deep tunnel sewer (largest PS in the world) and the decommissioning of 35 existing sewerage pumping stations. One of the key challenges faced by the implementation of the deep tunnel was related to tunnel ventilation and odor control. With the proposed tunnel route passing through some of the premier developed areas, the directive from higher authorities was clear; no odors and limited odor control facilities would be permitted. To accomplish the stated goal, a unique approach of several (regional) odor control systems were designed and installed along the new deep tunnel and at the downstream tunnel pumping station. Proper sizing, appropriate treatment technology, careful siting, and effective operation were required to ensure the deep tunnel, drop structures, and link sewers were well ventilated and maintained at a negative pressure under all normal operating conditions and that emissions were controlled to prevent offsite odor impacts. By so doing, odors would be contained and removed, helping assure ADSSC's goal of no odors would be achieved. Each regional odor control system consists of multiple extraction fans, first stage biotowers, a treated effluent water feed system, and final stage carbon polishing units. The regional odor control systems were designed to extract air directly out of the tunnel, retaining the concept of allowing drop structures to naturally ventilate link sewers and allowing the regional systems to extract the air collected within the tunnel for treatment. Given the size and complexity of this massive investment, the project design team elected to proceed with a physical model study during the design stage. The model study aimed to validate and refine certain design concepts associated with the drop shaft structures with an emphasis on hydraulic performance and the proposed odor control approach. In addition, CFD modelling of vortices and sewer hydraulics was performed to optimize the design. Moreover, liquid and headspace sampling of the sewer network was undertaken during the design stage as well as during the first years of operation when the Deep Tunnel Sewer was slowly taken online. A detailed analysis study was conducted a few years after initial start-up and commissioning for the purpose of quantifying performance and identifying areas of improvement. To address the challenges associated with analyzing the complexities associated with the existing tunnel and link sewers, a sewer process computer model was completed for simulating the various operating conditions and gaining understanding of possible root causes for some odor generation and fugitive emissions. The results of all measurements and the modelling were documented and analyzed, and some key findings from the study included: The main odor hotspots were identified:

Inadequate ventilation from the deep tunnel due to operational issues at the regional systems

Highly septic sewage entering the deep tunnel at several locations

Surcharging of local network pipe in some areas

Best fit solutions for each odor hotspot provided

This presentation will share some key lessons learned from (a) the design methodology during the detail design phase, (b) the commissioning during start-up phase, and (c) the first few years of operation.

Purpose: The purpose of this presentation is to provide the attendees with planning and design criteria and solutions when dealing with the design of a sewer lift station within a tsunami and sea level rise impact zone. Background: The City of Bellingham is located approximately 100 miles north of the City of Seattle in Washington State, 20 miles from the Canadian border. The city's Roeder Lift Station is located near the industrial area along Bellingham Bay and serves much of the northern part of the city. The existing lift station was suspected to be operating under reduced reliability conditions during peak storm events. The city contracted with Carollo Engineers to complete an alternatives analysis and design to increase the existing lift station's pumping capacity from approximately 8 million gallons per day (mgd) to 18 mgd. The existing dry-pit/wet-pit station is located on a small city-owned parcel of land surrounded by Port of Bellingham (Port) and Burlington Northern Santa Fe (BNSF) railroad properties. The station's existing 18-inch diameter force main is routed through a city utility easement on Port and BNSF properties including crossing under a BNSF spur track to reach the discharge manhole location. Two lift station retrofit alternatives and one new submersible lift station alternative were evaluated, including installation of a parallel force main alternative. The selected alternative included a new submersible lift station 1,100 feet north of its current location. The lift station design included a combination of variable speed driven non-clog submersible pumps and screw centrifugal pumps in self-cleaning pre-rotation basins with a pumping range of 1 to 18 mgd. Other improvements included 2,500 lineal feet of parallel 14-inch and 28-inch diameter HDPE force mains with trenchless installation beneath the railroad, installation of a 36-inch diameter PVC gravity sewer main and manholes, and miscellaneous 24-inch diameter HDPE water main replacement. Design Challenges: During the planning and design of the sewer lift station replacement, several design challenges came to light. These included the limited property owned by the city and the lack of a viable location near the existing station, the presence of a creek just west of the proposed station location, and issues related to the stations location near Bellingham Bay including tsunami and seal level rise impacts. The first challenge encountered by the design team was the lack of city-owned property near the existing station. Two of the replacement alternatives included retrofitting the existing station infrastructure while a third alternative included constructing a new adjacent station. The lack of property available to the city required relocating the proposed lift station. Further validating the need to relocate the station was the presence of Squalicum Creek approximately 2,000 feet upstream of the proposed station location. The existing gravity sewer crosses the creek before entering the station and the top of the pipe is exposed in the creek bed. The city has future plans to improve the creek which would require lowering the sewer line. An analysis was completed to look at installation of a deeper gravity sewer or installation of an inverted siphon. The two challenges having the greatest impact on the design of the new sewer lift station were sea level rise and tsunami impacts. Based on FEMA mapping, the location of the new lift station is within the 100-year flood plain. The potential impact of flooding became painfully apparent during November 2021 when a major rain event caused significant flooding at the proposed lift station site. Adding to the challenge, the FEMA flood maps do not take into consideration future long-term change due to climate change and the rising sea level. Sea level rise predictions for our project area ranged from 1.1 to 11.7 feet above the base flood elevation. Through multiple modeling efforts the design team settled on a sea level rise impact of 1.5 meters and a 100-year storm event to set the initial water surface elevation used for design. The final challenge impacting the design of the replacement lift station was the fact that the new site was located within the Tsunami Design Zone. With the State's adoption of the International Building Code, we were required to use the Washington Tsunami Design Zone Map to determine whether Risk Category III or IV structures needed to be designed for tsunamis. The tsunami inundation elevation at the project site was identified as 21 feet based on mapping. Ultimately, the impacts related to tsunami inundation controlled the site design and the new station was elevated 9 feet above the existing grade. Status and Conclusions The project was bid for construction in April of 2023 with an engineer's estimate of $18 million including tax. The city received four bids ranging from a low bid of $17.5 million to $21 million. The project is currently under construction with an estimated completion date of Spring 2026. The design of the replacement sewer lift station was impacted by multiple surrounding water bodies which lead to many lessons learned throughout the design. Scour within Squalicum Creek caused exposure of the existing gravity sewer line. Future improvements to the creek impacted the depth of the future sewer upgrade requiring a deeper lift station wet well. This factor required construction of a new lift station and would not allow retrofit of the existing station. The location of the new lift station site and its proximity to Bellingham Bay caused the need to design for sea level and tsunami impact zones. Lessons that were learned during the design included understanding that FEMA flood plain mapping does not take sea level rise into account and that tsunami inundation can have a more significant impact on the final grade of the proposed site. Additionally, the design of the on-site structures themselves relative to the thickness and strength of the structure walls can be affected by the potential for tsunami impact loads. Finally, construction in a historically intertidal zone overlaid by fill required ground improvement design to stabilize the soils before construction could begin.

Odor Control Technology isn't Enough Without Effective Capture Effective odor control is not just about the technology, it is also about the capture and containment of the odor. Choosing and sizing a wet scrubber or any odor control technology is critical, however the best technologies are insignificant if nuisance odors continue to escape before they can be treated. Such issues with capture and containment of odor were present at Orange County Sanitation District (OC San) Plant No. 2 biosolids Truck Loading facility. OC San Plant No. 2 is located in Huntington Beach, California, along the Santa Ana River (which has a raised walking/bike path) and is located near residences, Huntington State Beach, a few parks, and some commercial properties. The Plant is currently treating an average wastewater flow of approximately 60 million gallons per day (MGD). The function of the Truck Loading facility is to store the dewatered biosolids and to load to the hauling trucks for offsite beneficial reuse. Newly installed centrifuges, which improved biosolids dewatering, increased odor generation at the storage and Truck Loading facilities and triggered complaints by plant personnel and community members. To address these nuisance odors, a scientific approach was implemented that consisted of four main parts: gathering data, targeted sampling, air movement monitoring, and designing a custom air capture system based on the information collected in the previous steps. This paper will provide an overview of the approach utilized and highlight key elements that aided in understanding and solving the problem. Gathering Data: A series of questions were asked to find where and when the problem was occurring. To understand and solve the problem, collaboration with the OC San Maintenance, Operations, and engineering staff was crucial. Through this collaboration, it was determined that the odor in the Truck Loading bays was caused by the centrifuge-dewatered biosolids in the truck loading operation. Odors were released when the biosolids dropped through the storage silo knife gate valves and filled the truck trailers. Odors continued to be released from the accumulation of biosolids on surfaces of the truck and Truck Loading bays from the loading process. Minor system contributors included fugitive odors where biosolids accumulate but were difficult to clean, including the floor grates associated with the truck scales, which trap biosolids from washdowns. This information determined that the central issue surrounding the Truck Loading facility was the lack of containment infrastructure. Continuous dataloggers were installed to identify the pattern of hydrogen sulfide and ammonia occurrence throughout normal operations for several weeks. Trucks generally drove into the loading bay from the north, where a door closed behind it, to prevent the wind from blowing the odor out through the facility. The original design of the building assumed that winds would dominate from the south side, and that thus air would be sufficiently contained by the door on the north while ventilation drew out the foul air. The presence of odors indicated that this design was less effective than anticipated in capturing the stronger lingering odor, and further analysis was needed to determine the best containment and ventilation approach. Targeted Sampling: Next targeted sampling was conducted to quantify the odor by pinpointing the constituents of the odor, and their concentrations so that effective capture and containment can be customized. This sampling and analysis measured a complete set of odor-causing constituents such as hydrogen sulfide and ammonia on a continuous basis as well as grab samples for other speciated reduced sulfur compounds/VOCs during the most concentrated periods of Truck Loading, at the higher areas of the loading bay, as well lower regions of the bays (Understanding that the mix of compounds present consisted of both heavier and lighter than air compounds). Air Movement Monitoring: Air movement in the Truck Loading bays was simulated using a series of smoke tests for both existing and considered future conditions. The smoke tests were conducted with smoke candles that released a large amount of smoke (up to 40,000 cubic feet) within a small period of time, to simulate the sudden release of odor while the trucks were being loaded. Each test simulated either existing or potential ventilation conditions. Potential conditions included simulating the presence of a door on the south side of the building, differing ventilation rates, and differing quantities of supply air provided. By observing the movement of the smoke during this array of conditions, conclusions were drawn about the movement of odor throughout the truck bay, including the locations of dead zones, the effectiveness of an additional door on the south side for containment, and the effectiveness of the existing ventilation system at clearing air through each region of the truck bay. The smoke tests made it clear that a second door was necessary to contain the smoke within each bay. Tests which simulated a door made clear other weaknesses with the existing ventilation system's layout, including dead zones near the ceiling. Design of a custom system: The above tests and observations indicated the specific problems that were causing issues with odor control at this particular facility. Alternatives evaluation and conceptual design of improvements to the system were entirely customized to the height and length of the building. First, a door was recommended on the south side of the Truck Loading facility, to contain the odors within the building. Positive air supply was recommended at low and high heights to move foul air with odorants heavier than air observed in step 2, and sweep dead zones found near the ceiling in step 3. A U-shaped exhaust duct layout at ceiling level was recommended to capture the most concentrated foul air on both sides, where the smoke tests indicated most of the smoke was accumulating. The above method of identification of the distinct contributors to the odor control issue at this facility was instrumental in creating a custom design to address the concerns thoroughly and efficiently. Without the observations and collaboration in the earlier steps, the conclusions that allowed for a custom solution would not have been possible.

The Inflation Reduction Act (IRA), signed August 2022, brought sweeping changes to how water and wastewater utilities evaluate project opportunities as United States continues to push the energy transition.The IRA is the largest energy incentive legislative effort in U.S. history, providing unique opportunities for public and private utilities. For the first time, tax-exempt organizations can obtain tax credit funding through direct payments - for qualifying clean energy or efficiency projects. These tax credits can total as much as 50% or more of the qualifying project costs. Many utilities are already taking advantage of these tax incentives which can reduce local funding requirements. Qualifying project examples are solar for water or wastewater treatment plants, waste energy recovery for wastewater treatment plants and more. Sustainability projects for utilities which qualify for the IRA tax credits include biogas, solar, clean hydrogen, wind, hydro, electric vehicles and more. In certain circumstances the cost of the equipment, such as biogas at wastewater treatment plants, is only a small portion of the eligible property for the tax credits. This presentation will provide an overview of the IRA, the utility sector's approach and general trends related to the IRA in the early stages including the significant requirements related to maximizing the credit amount. Relevant lessons learned and case studies in the first year of this impactful legislation will also be shared. [u]Learning objectives[/u] Participants of this educational session will be able to: 1. Outline current tax incentive opportunities pertaining to utilities 2. Understand examples of qualifying projects 3. Determine qualifying projects for one's utility

Introduction The Metropolitan Water District of Southern California (Metropolitan) and the Los Angeles County Sanitation Districts (Sanitation Districts) are collaboratively exploring water recycling possibilities through the Pure Water Southern California (PWSC) project. The full-scale endeavor would involve the construction of an Advanced Water Treatment Facility (AWTF) with a capacity of 150 million gallons per day (MGD) at the Sanitation Districts' A.K. Warren Water Resource Facility (Warren Facility) in Carson, CA, previously known as the Joint Water Pollution Control Plant. The AWTF would produce treated water for indirect potable reuse, with potential for direct potable reuse in the future. The Warren Facility, with a capacity of 400 MGD, currently operates as a high purity oxygen activated sludge (HPOAS) facility and discharges its treated effluent (non-nitrified secondary effluent) into the ocean. Metropolitan has established the Grace F. Napolitano PWSC Innovation Center (Napolitano Center) to formulate the design and operating criteria for the 150 MGD AWTF, while ensuring compliance with regulations. Within the Napolitano Center, a demonstration plant with a capacity of 0.5 MGD has been developed. The Napolitano Center's process train comprises a membrane bioreactor (MBR), followed by reverse osmosis membranes, and ultraviolet light with an advanced oxidation process. Nitrogen management is a pivotal aspect of the PWSC project. Consequently, the Napolitano Center's MBR process was designed with flexibility to accommodate different nitrogen removal configurations. The full-scale implementation of biological processes aimed at transforming or removing nitrogen may result in an increase in greenhouse gas (GHG) emissions from the Warren Facility. A specific concern revolves around nitrous oxide (N2O), primarily generated during nitrification and denitrification processes in wastewater treatment plants. N2O is a potent GHG, with the Intergovernmental Panel on Climate Change (IPCC) estimating its 100-year warming potential at 296 times that of CO2 (Ehhalt et al., 2001). Estimating, measuring, and, when necessary, mitigating GHG emissions that contribute to climate change are integral components of the broader sustainability and public health mission in wastewater treatment. The Sanitation Districts have demonstrated a strong commitment to sustainability, achieving carbon-negative status in both 2021 and 2022. Greenhouse Gas Emissions from Wastewater Treatment In the context of GHG emissions, wastewater treatment facilities play a relatively minor role in the overall emissions landscape. To provide perspective, in 2022, these facilities accounted for just 0.8% of the total US GHG emissions, equivalent to 41.8 million metric tons of carbon dioxide equivalents (MMT CO2eq). More specifically, wastewater treatment contributed 2.8% of the total US methane (CH4) emissions and 5.5% of the total N2O emissions (EPA, 2022). Despite their relatively modest overall contribution, there is considerable variability among individual facilities and processes. For instance, a 2010 study conducted by Ahn et al., which investigated N2O emissions from ten wastewater treatment plants, uncovered a wide range of emissions, from 0.0001 to 0.071 lb N2O/lb N-day for a given plant. In a more recent study by the IPCC, encompassing the ten plants studied by Ahn et al., along with an additional 20 facilities, emissions were reported in the range of 0.0003 to 0.071 lb N2O/lb N-day (IPCC, 2020). For the purpose of GHG inventorying, the IPCC and the United States Environmental Protection Agency (U.S. EPA) have established default emission factors for wastewater treatment plants based on available data, with values set at 0.016 and 0.015 lb N2O/lb N-day, respectively (IPCC 2019, U.S. EPA 2021). These default values are derived from the available data and, as such, they can result in substantial overestimation or underestimation of actual GHG emissions at an individual facility. Therefore, the accurate measurement of process emissions becomes essential in ensuring precise GHG inventorying and the evaluation of new treatment processes. Project Objective and Emissions Measurement Description To assess the potential N2O emissions resulting from the implementation of a large MBR process at the Warren Facility, emissions were measured from the Napolitano Center MBR process. In May of 2023, the system operated as a secondary MBR process, with a primary effluent feed flow of approximately 0.5 MGD and an average Total Kjeldahl nitrogen (TKN) concentration of 70 mg N/L (Figure 1). In this configuration, primary effluent was introduced into an anoxic tank to supply carbon for denitrification. Subsequently, this liquid was directed to the aerobic tank, where ammonia was nitrified to nitrate. The nitrified water was then recycled back to the anoxic tank for denitrification. These processes were then followed by membrane filtration conducted in separate membrane tanks. A fraction of the solids retained by the membranes was continuously returned to the front of the aeration tank. For emissions measurement, the anoxic and aerobic tanks were temporarily enclosed using scaffolding and plastic sheeting, which was connected to metal ductwork and an exhaust fan (Figure 2, Figure 3). One of two membrane tanks was also covered with plastic sheeting and connected to metal ductwork and an exhaust fan. Each tank was maintained under negative pressure during the emissions measurement process. Full enclosure of the tanks captured the emissions from the tank surface area and, as such, the resulting emission estimate would not be subject to the spatial variabilities that tend to affect studies that utilize other measurement techniques, such as probes or floating emissions capture systems. In the first two weeks of May 2023, gas-phase N2O emissions were monitored from the fully enclosed aerobic, anoxic, and MBR tanks using a calibrated Innova photoacoustic sensor (PAS) (Innova Air Tech, Denmark) configured to record data at two-minute intervals. Standards were run daily, and the lab analyzed 24 grab samples for comparison with the PAS data. Emissions were assessed over approximately 24-hour periods for each tank, involving four days of measurements for the aerobic tank, two days for the anoxic tank, and one day for the MBR tank. In the case of the aerobic tank, both steady-state and induced process upset emissions were recorded. The determination of emissions used the concentration (in parts per million, ppm) as recorded by the photoacoustic sensor and the measured gas velocity within the ductwork. Emission factors were calculated as the fraction of influent nitrogen lost as N2O and as the mass N2O emitted per MGD. Project Results As anticipated, under steady-state conditions, the aerobic tank exhibited the highest N2O emissions factor of 0.0008 lb N2O/ lb N. The average aeration rate of atmospheric air was 300 standard cubic feet per minute (scfm). In contrast, the anoxic tank and the MBR tank recorded emissions of 0.0004 lb N2O/ lb N, resulting in an overall process emission factor of 0.0016 lb N2O/ lb N (0.16%) or 0.96 lb N2O/MG. It's worth noting that during steady-state operation, the anoxic tank utilized low-intensity aeration at a rate of 100 scfm. Replacing this mixing method with mechanical mixing could reduce emissions from this tank by minimizing stripping. The MBR tank maintained an average air flow rate of 180 scfm. In the broader context, it's important to highlight some limitations in this study. The data collection suffered from limited temporal resolution, as it was conducted over a two-week period during a single season. Nevertheless, despite these limitations, the overall process emission factor of 0.0016 N2O-hr/ lb N-hr was an order of magnitude lower than the emission factors established by the EPA and IPCC, which are 0.015 and 0.016 N2O/ lb N, respectively (IPCC 2019, U.S. EPA 2021). This is particularly noteworthy, given the use of aeration mixing in the anoxic tank, which might have increased emissions from that specific tank. Additionally, it's worth noting that the overall emission value falls within the lower end of the range reported in the IPCC study of thirty facilities, where emissions ranged from 0.0003 to 0.071 lb N2O per lb N processed per day (IPCC, 2020).

Introduction: The water and wastewater industry is facing new challenges in the chemical supply chain due to recent pandemic conditions, hurricanes, and wildfires. As a result, Water Resource Recovery Facilities (WRRFs) are looking ways to improve the chemical resiliency of their facilities during chemical shortages, emergencies, or any disruption in chemical supply chain. The main objective of this paper is to assess the risk from chemical shortages, and present strategies to WRRF's to mitigate risk through consequence and vulnerability reduction. Background: Recently, Hazen has teamed with Orange County Sanitation District (OCSan) to conduct the Chemical Resilience Study for their Plant 1 and Plant 2. The approach to quantitatively assessing and managing risk is based on the ANSI/AWWA J100 Standard: Risk and Resilience Management of Water and Wastewater Systems. The J100 standard provides the framework for assessing baseline conditions as well as improvements following the implementation of risk mitigation. Risk is defined as follows: RISK = Consequence X Vulnerability X Likelihood Table 1 summarizes the approach to reduce consequence and vulnerability for OCSan. This approach will allow to assess baseline risk for WRRFS, as well as provides clear path to reduce the risk, either by reducing the consequences of supply disruption or improving system resilience (i.e., reducing vulnerability). Table 1: Approach Adopted to Reduce Risk for OCSan Methodology: The following methodology was developed to reduce the risk of WRRFs to chemical shortages and disruptions - Chemical Risk Analysis: Estimating the likelihood of chemical shortage requires understanding the chemical supply chain and availability of substitutes. Industry trade groups and chemical suppliers were contacted to understand manufacturing locations and the sources of raw materials. - Vendor Alternatives. Alternative vendors were identified using information from industry trade groups, as well as reviewing chemical bids from OCSan and similar utilities. The use of chemicals in other industries which might be supplied by alternate vendors was also reviewed. - Delivery Alternatives. Alternative forms of deliveries including bulk liquid, totes, and dry chemical delivery with onsite dilution were also investigated - Chemical Alternatives. Alternative chemicals were identified to existing chemicals Findings The chemicals evaluated in OC San Chemical Resilience Study are grouped under four main categories and listed in Table 2. These chemicals are used in the following plant process areas: preliminary treatment, primary treatment, secondary treatment, odor control, effluent disposal, solids handling, and power generation. Table 2: Chemicals Evaluated at OCSan Chemical Resilience Study Chemical interruption to facilities could result from the following conditions: - Lack of delivery access due to a natural disaster - Interruptions from manufacturers and/or vendors - Chemical shortages - Increased cost of chemicals - Increased demand in other industries - Delays in deliveries - Regulatory changes Evaluation of the baseline conditions for OCSan's chemicals identified that most chemicals used have over two weeks of storage available in the event of interruption. The only chemical with less than a week of storage capacity was ferric chloride at Plant 1. Ferric chloride is the mostly used and frequently delivered chemical at Plant 1 and Plant 2 with less than 3 days between deliveries. Bleach was also identified as a chemical with frequent deliveries at Plant 1. Both ferric chloride and bleach are critical chemicals in order for OC San to meet permit requirements in their air quality and discharge permits. Table 3 was developed for OCSan to highlight the criticality (based on consequence score), average chemical use, and consequences of chemical interruption for chemicals used at Plant 2. Table 3: Summary of Chemicals Used at Plant 2 Figure 1 shows the overall risk score calculated for the chemicals used at OCSan. The score brings together the consequence, vulnerability and likelihood assessments. As can be seen in Figure 1, Bleach and Ferric chloride have the highest risk for chemical disruptions. Our full paper will include more details about the consequence, vulnerability and likelihood assessments and will provide a list of alternative chemicals that could be used to replace existing chemicals. Figure 1: Risk score for chemicals used at OCSan

Introduction Sludge generated from wastewater treatment typically goes through a series of handling processes such as thickening, stabilization and dewatering, before its final use or disposal. Anaerobic digestion is widely applied in medium to large water resource recovery facilities (WRRFs) for sludge stabilization. In anaerobic sludge treatment, fugitive methane emissions can occur from digesters (due to aging infrastructure), downstream storage, from associated pressure relief valves and pipework, and also due to methane slip through combined heat and power (CHP) engines and biogas upgrading. For example, work in Denmark over the past few years has quantified methane emissions at 69 biogas facilities and shows methane emissions account for up to 7.5 percent of the gas production at WRRFs (Fredenslund, A.M et al., 2021; Scheutz & Fredebslund, 2019). Large leakage of methane may negate the positive climate impact from biogas energy recovery and contribute significantly to the facility's operational carbon footprint. A portion of the methane generated is dissolved in the digestate, which can also be released during the downstream dewatering or sidestream treatment processes. In addition, long-term sludge drying (e.g., in lagoons) is commonly applied in many countries, such as Australia, due to its ease of operation and low operational costs. Methane generated from sludge drying lagoons is typically not captured and can be a significant greenhouse gas (GHG) emission source. In the US, a country-wide standard methodology for quantifying GHG emissions from the wastewater sector does not exist. Among the available reporting protocols, methodologies for quantifying fugitive methane emissions from sludge treatment and biogas handling are limited to combustion of biomass and biogas, which essentially assumes zero methane emissions from anaerobic digestion and biosolids dewatering processes. The latest Biosolids Emissions Assessment Model (BEAM 2022) has recommended a minimum of 1 percent of methane in biogas as fugitive emission and allows a user-input value if site-specific data are available. The lack of consistent methodology and lack of facility level measurement result in significant risk to facilities in the estimation of their fugitive methane emissions through the sludge treatment and biogas handling processes. This paper presents an overview of challenges and issues in quantifying fugitive methane emissions from sludge treatment and biogas handling, impacts on GHG inventory and practical tips for reducing methane emissions based on global experience to date across a growing number of case studies. Benchmarking Fugitive Methane Emissions Methodologies and Key Considerations In the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, a three-tier method is described for quantification of methane emissions from WRRFs. Tier 1 provides global activity and emission factors; Tier 2 provides for local in-country activity factors and/or emission factors and Tier 3 methods require facility level monitoring. Accurately quantifying fugitive methane emissions requires Tier 3 facility level measurement using methods such as differential absorption lidar (DIAL), tracer gas dispersion (TDM) and inverse dispersion modelling (IDM), which may be combined with point source leak detection or other process unit methods to determine location of leaks. This practice remains emerging with significant work ongoing in Europe to provide facility level quantification and mitigation at WRRFs. Elsewhere, Tier 2 methods are common. The UK Carbon Accounting Workbook is used by Utilities to report on operational emissions and includes country-specific (Tier 2) theoretical emission factors associated with the most common sludge and biosolids processes in the UK, with emissions based on mass of methane per unit of tonnes dry solids of raw sewage sludge (UKWIR, 2020). In the Australian National Greenhouse and Energy Reporting (NGER) framework, methane process emissions are indirectly estimated using sampled influent and/or effluent streams and application of assumed biogas generation and percentage biogas utilization to calculate the net tonnes of CO2 equivalent released to the atmosphere. This approach considers facility level data but does not require direct measurement of the GHG, hence still considered Tier 2. Emissions from biogas flaring is based on best practice flow rate measurements of the flared biogas and its methane concentration. Different facilities may have a range of approaches to sampling process streams for operational, planning or reporting requirements. Sampling locations, frequencies and methodologies can result in inaccuracies in estimating the fugitive methane emissions. The recently published IWA book 'Quantification and Modelling of Fugitive Greenhouse Gas Emissions from Urban Water Systems' includes additional information on fugitive methane emissions from a range of wastewater treatment, sludge and biogas handling processes, estimated through facility level monitoring (IWA, 2022). Table 1 provides a summary of key methane emissions from global case studies including both those which directly monitor methane emissions and those which use various alternative GHG accounting methodologies, generally aligned with Tier 2 level approaches. A more complete table will be provided in the full paper. In the absence of global full scale monitoring data to estimate fugitive methane emissions, existing methodology estimates may be beneficial for benchmarking emissions from sludge treatment and biogas handling processes however, Tier 3 level facility monitoring is required to accurately estimate methane emissions and to validate any mitigation efforts. Monitoring and Reducing Fugitive Methane Emissions Whilst published literature studies of methane mitigation are limited, practical examples of programs for monitoring and mitigation across European countries show the criticality of direct methane emissions monitoring, and operational approaches to mitigate methane emissions through regular survey, proactive leak detection and repair and independent certification. Table 2 summarizes some of the key sources and (limited) mitigation approaches from work to date; further details to be provided in the full paper. In future planning, it is critical that decisions regarding anaerobic versus aerobic sludge digestion consider fugitive emissions from existing and proposed assets. Conclusions Fugitive methane emissions from sludge treatment and biogas handling processes are a significant source of GHG emissions which must be monitored and mitigated by utilities taking action to reduce their carbon footprint. These emissions are particularly critical for WRRFs with anaerobic digestion and open anaerobic systems such as sludge drying ponds. There is lack of consistent methodology for quantifying and monitoring these emissions in North America, which could lead to over- or (more likely) underestimation of their contributions to the overall GHG footprint for the WRRFs. As shown by ongoing work in Europe, facility level measurement is critical in quantifying the fugitive methane emissions. This paper will provide practical recommendations to WRRF operators to guide best practices for methane monitoring and mitigation throughout the facility life cycle.