The Southeast Michigan Council of Governments, SEMCOG, recently finalized a 7-county analysis of water infrastructure investment needs through 2045 for linear drinking water, sanitary sewer and stormwater assets. Based on the findings, an estimated $3.5 billion is necessary for continued protection of public health. Combined with transportation investment needs, the total annual investment is nearly $5 billion just to keep linear assets in good condition. This does not take into account other significant investment needs to address water treatment, wastewater treatment and extreme flooding events. With recent (June – July 2021), severe flooding events in the 7-county, Southeast Michigan Region, regional flood mitigation planning for future infrastructure investments has risen to the forefront. To support local, regional and state infrastructure planning efforts, SEMCOG is utilizing results from a future precipitation analysis, a flood risk study, and a regional asset data collection and condition assessment effort to address increased rainfall and extreme flooding events. Based on the future precipitation analysis, it is expected that the lack of stormwater collection capacity and flooded property and roadways will be exacerbated unless there are significant investment efforts and implementation of a collaborative management strategy. This presentation will share findings and products from that address regional climate resiliency including: - Precipitation estimates using regional climate models for 2050 and 2100; - A flood risk tool for transportation assets including roads, bridges, culverts, and pump stations; - A flooding app to track localized flooding locations; - A regional guidance document with alternatives to addressing future rain events in infrastructure planning and design; - Water infrastructure investment need estimates and background methodology for continued updates; and - A collaborative capital improvement project coordination tool across public and private utilities for future infrastructure planning. These regional projects represent valuable insight into the interwoven practices of transportation planning, stormwater management, and capital improvement investment. Learning Objectives Attendees of this session will learn about the methodology to estimate investment needs across a large regional metropolitan area. They will also learn about the flood risk tool for roads, bridges, culverts and pump stations; the flooding app to track local flooded locations; and their applicability in the long-range transportation planning process. Additionally, participants will learn of the future precipitation estimates for the region for small and large rain events and understand alternative approaches to integrating these estimates into planning/design efforts. Finally, attendees will understand how the region is supporting more coordinated project planning efforts for long-term cost savings and protection of public health.

Per- and Poly-Fluoroalkyl Substances (PFAS) are a large family of organic compounds, including more than 4,000 synthetic fluorinated organic chemicals used since the 1940s. PFAS have unique surfactant properties that make them repel both water and oil. Because of these properties, they have been used extensively in firefighting foams, surface coatings, and protectant formulations for consumer products, including paper and cardboard packaging products, carpets, leather products and clothing, construction materials, and nonstick coatings (ITRC, 2020). Manufacturers of these items often discharge to Water Resource Recovery Facilities (WRRFs). Landfill leachate discharge and household sewage are also common sources of PFAS in WRRF influent. Conventional WRRFs have proven to be relatively ineffective in removal of PFAS and discharge from WRRF is considered a major source of PFAS in the environment (Ahrens 2011, Chen et al., 2018). There is mounting evidence that continued exposure above specific levels of certain PFAS may lead to adverse health effects (USEPA 2016a, 2016b, ATSDR 2018a). PFAS concentrations in wastewater and sludge or biosolids are mass loading based. Long chain PFAS compounds discharged into WRRFs partition to the solids and end up in the resulting sludge or biosolids. The presence of PFAS in WRRF biosolids has raised a concern in the recent years for beneficial land application programs as PFAS could mobilize in soil, leach into run-off, infiltrate into groundwater or be taken up by biota (Lindstrom et al. 2011, Rich et al. 2015, Sepulvado et al. 2011). Within the PFAS family of compounds, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the two most common compounds and are a focus of Federal and State drinking water and environmental regulations. These compounds were commonly used in the manufacture of aqueous film forming foams (AFFF) for fighting aircraft fuel fires and other industrial and commercial products. In February 2019, the US EPA developed an action plan to limit human exposure to potentially harmful levels of PFAS in the environment. The short-term action plan includes testing for measurable PFAS and PFAS precursors in biosolids. The action plan was updated in February 2020 indicating that EPA is developing a risk assessment to better understand the potential public health and ecological risks associated specifically with PFOA and PFOS in land-applied biosolids. With mounting concern about the presence of PFAS in biosolids and the lack of specific guidance from the US EPA regarding the risks of these compounds within biosolids, some states have begun their own evaluations on this topic with suggested concentration limits of PFAS in biosolids used for land application. However, state regulatory agencies do not have a consistent approach to managing PFAS in biosolids. These concerns coupled with lack of consistent guidelines from the US EPA and state regulators has caused utilities to consider alternatives to eliminate the presence of PFAS in biosolids to minimize their risk exposure to potential future regulatory standards. As a result, technologies which can effectively destroy PFAS in biosolids based products are being investigated. One such technology is pyrolysis. Pyrolysis is the conversion or cracking of biomass or biosolids at high temperatures in the absence of oxygen. As most organics are thermally unstable, they can be split in a pyrolysis process by a combination of thermal cracking and condensation reactions into gaseous (pyrogas), liquid (bio-oil), and solid (biochar) fractions. With limited research available on the ability of pyrolysis to eliminate PFAS from biosolids and the fate of PFAS in the resulting effluents (solids, liquid, and air), there is a need to provide actual data for engineers and planners to evaluate as to the actual performance of the pyrolysis process with respect to PFAS reduction and fate. Jacobs and CharTech Solutions (CharTech) recently partnered to investigate the application of CharTech's High Temperature Pyrolysis Technology for biosolids management, and its efficacy in eliminating PFAS from the solid fraction. In addition, the transformation or elimination of PFAS compounds by measuring concentrations in the resultant bio-oil and pyrogas produced from the pyrolysis process were evaluated. This is one of the first analyses done using dried biosolids which captured PFAS data from the all output matrices including the resultant char, bio-oil and pyrogas fractions resulting from the pyrolysis of biosolids. Bench scale testing was performed in a continuously fed pyrolysis unit to compare the PFAS removal performance at 500 °C and 700 °C pyrolysis temperatures. Dried biosolids tested in the bench scale test were derived from un-stabilized waste activated sludge produced from two WRRFs operated by Jacobs. The solids were previously dewatered with belt filter presses to approximately 20 percent solids and subsequently dried in a batch thermal dryer fired with natural gas to evaporate water, resulting in a biosolids product that was approximately 93 percent solids. The dried biosolids material previously met Class A Exceptional Quality biosolids product status by achieving all pathogen and vector-attraction reduction requirements, as well as meeting the concentration limits of heavy metals according to the U.S. Environmental Protection Agency's (EPA) 40 Code of Federal Regulations (CFR) Part 503 Rule. Twenty eight of the most commonly measured PFAS compounds were analyzed in the feed biosolids, biochar, bio-oil and 31 PFAS compounds were analyzed in the pyrogas. Only six PFAS compounds (10:2 Fluorotelomer sulfonic acid, PFOS, N-Et PFO sulfonamidoacetic acid, N-Me PFO sulfonamidoacetic acid, Perfluorohexanoic acid, and Perfluoroundecanoic acid) were measured above the detection limits in the feed biosolids. Three PFAS compounds were detected in the biochar at the 500 °C pyrolysis temperature (Perfluorohexane sulfonic acid, Perfluorohexanoic acid, Perfluorooctanoic acid), all at less than 0.5 ppb (dry weight). No PFAS compounds were detected in biochar at the 700 °C pyrolysis temperature. PFOS was measured at 26.6 ppb in the feed biosolids but not detected in the biochar, bio-oil or pyrogas at either pyrolysis temperature. Although not detected in the dried biosolids, PFOA was detected at very low concentrations in biochar and pyrogas indicating a lack of complete destruction and/or transformation of precursor compounds during pyrolysis. Higher concentration of Perfluorohexanoic acid (PFHxA) in pyrogas at 500 °C compared to 700 °C was observed, suggesting greater destruction of PFHxA at a higher temperature. To better understand the PFAS fate through the pyrolysis process, mass balance analysis on biochar, bio-oil and pyrogas streams were conducted and removals of PFAS were estimated. The result of mass balance analysis indicated a total measured PFAS mass removal of 84.4% and 95.6% for 500 °C and 700 °C, respectively for all the PFAS tested in this study. This paper will describe in detail the testing apparatus and procedures used and provide a full description of the results measured. The information will be useful for engineers, planners, scientists, utilities, regulators and others interested in the evaluation of pyrolysis as a potential biosolids management alternative to minimize PFAS in biosolids.

For the past several years, the Water Environment Federation 'Recommendations to Improve the Stormwater Program in the U.S.' included 'Improve[ing] Stormwater Infrastructure Needs Data Collection.' The recommendation asks State Revolving Fund program managers to ensure that stormwater assets are included during Clean Watershed Needs Survey (CWNS) data to support advocacy for increased stormwater funding. Historically, less than half of states have reported stormwater asset needs in the CWNS. Today, few communities conduct proactive condition assessment and comprehensive master planning for stormwater systems and lack an understanding of long-term compliance costs. For stormwater needs to receive national recognition, program managers need to understand the condition of their assets, short and long-term costs, and the staffing and labor necessary to sustain their programs. If we can't clearly define our infrastructure, resiliency, compliance, and planning needs, we can't expect to get critical funding for it. In 2022, the EPA is conducting the next round of CWNS. This is an important opportunity for stormwater programs. The states often relying on local wastewater utilities to generate documentation that meets EPA standards. To meet these standards, all documents must clearly define the NEED, the SOLUTION, and the COSTS of the solution. Typical wastewater supporting documents include Asset Management Plans, Intended Use Plans, various grant and loan applications, and Facility Plans, among others. Stormwater programs may have documents like Preliminary Design Reports for clean water obligations under Combined Sewer Overflow Long-Term Control Plans, Watershed Management Plans (name varies among states) for impaired waters with implementation cost estimates, grant or loan applications, or Stormwater Master Plans, among others. Many stormwater programs, however, do not have these more traditional engineering reports or capital. EPA has suggested that alternative documentation is permittable, if approved by the agency. This presentation will provide an overview of alternative documentation approaches considered in EPA Region 1, the documentation generated for stormwater needs, and a detailed overview of the approach taken with the state CWNS coordinators. It will complement the EPA CWNS update proposed in an abstract from the EPA National Office, providing additional details on alternative documentation. It could be set up as part of a panel discussion suggested by NMSA on the future of the CWNS and how the stormwater community can better position for future needs documentation.

The City of Clive is rich in water resources. The geography of the watershed graces the city with miles of creekside bike paths and recreation. However, that same benefit of proximity, also creates a challenge for protecting property and assets during rain and high-water events. The challenge with this project was to create a framework and program to comprehensively address the needs of the traditional stormwater network while also addressing the surface water, creek condition, and various green stormwater controls throughout the City. The project included a modeling evaluation to prepare for extreme weather flooding events, examining staffing to address the full service needs for all stormwater drainage assets, fully developing an asset management inventory, creating a financial plan that adequately address the needs of the City utility, and creating communication tools to share this information with both the City's citizens but also with critical partners in the Walnut Creek Watershed and Des Moines River Basin. Financial responsibility is a cornerstone of the City's value system. The current stormwater utility has near zero debt service and a positively growing fund. City construction projects comply with uniform standards for stormwater management required of development projects. The City selected a new project evaluation methodology to continue to be forward thinking and financially sound. The comprehensive analysis will support decision making, equity in rate structure, and policy to support the shared benefits and burdens of the water resources assets. The Water Resources Master Plan took care to reflect the authentic vision of the City and its citizens. The approved vision includes statements regarding the City's relationship with the greater watershed, its approach to resiliency, the quality of life provided for its residents, and creating amenities where one can recreate safely. The vision statement laid the foundation for the evaluation criteria for all capital improvement projects. A defensible score to compare varied projects was necessary for the utility. The benefit score was then balanced with the financial obligations and needs of the utility. The financial evaluation tool created for this project allowed for multiple scenarios and approaches to be evaluated and compared quickly. Finally, the implementation plan including a tactical step-wise approach for how to implement sustainable change and a dashboard to track key performance indicators was developed to monitor and measure progress year to year. The presentation will highlight the challenges and provide others a guide to how we incorporated previous studies to break department silos and make final recommendations cohesive to the utility, adapted a public engagement plan to pivot from broad education and instead associate education with a direct action (impervious cover with rate changes, infiltration potential with incentive program, and green stormwater infrastructure controls with a targeted pilot plan), and finally how we designed our management tools to be adaptive. Over time, we should improve and consequently, our goals should change. Our targets will be adjusted. Our tools reflect reality and therefore are not static.

Population growth brings capacity issues, climate change brings increased frequency and intensity of storm events, and ongoing system blockages from FOG result in overflow conditions that impact our communities and the environment. Municipalities are subject to ever-tightening regulatory oversight where high cost consent decrees for sanitary sewer overflows (SSOs) and combined sewer overflows (CSOs) are becoming the norm. The typical response is expensive capital upgrades to collection system infrastructure and high frequency cleaning of collection system segments on a schedule. Faced with uncertainty, municipalities are staring down the prospects of significant infrastructure investments and billion-dollar consent decrees to protect residential property, local businesses and waterways -- without a significant increase in resources. Despite the potential penalties and the prospect of massive capital projects, the benefits they may produce are decades in the making and consume billions of dollars of municipal revenue. It is imperative, then, that we begin to understand the real-time operation of our existing collection system infrastructure to maximize utility, minimize costs and target investments to the appropriate and highest risk areas. For more than 500 sewers around North America, the solution involves innovative turbo charging of their collection system engine to take an aggressive stance on risk management. A data-driven early warning system designed combines a real-time view of the sewer and stormwater networks, weather and storm data and real time notifications allowing them to be proactive in responding to conditions and detecting emergencies before an overflow. Those who attend 'Turbocharged Engines' will learn how agencies of varying size are using real-time sewer monitoring technology to provide actionable information in order to protect the environment, safeguard public health and optimize investments in maintenance and capital improvements. Many collection systems adhere to the EPA's comprehensive capacity assurance, management, operations and maintenance (CMOM) programs to prevent CSOs and SSOs. Such measures include backup pumps, frequent cleaning in high-risk areas, capital projects and flow reduction measures that maintain the pipes at their design capacity. While these programs can be effective, they often do not allow utility staff to be proactive – particularly in the face of rapidly evolving events. To provide that next level of understanding, control and response, three cities in Texas turbocharged their sewer intelligence with real-time visibility into the status of their underground infrastructure. These municipalities deployed a network of SmartCover systems to provide real-time sewer level and trend analysis information to a centralized, online dashboard and mobile app. Designed with the unique challenges of a collection system in mind, the technology transmits data from a sensor in the manhole to a satellite in the sky to relay reliable sewer information throughout all conditions – a particular benefit in places like Texas where weather events can often disrupt terrestrial communications. The patented sensors are purpose-built to withstand the harsh conditions in sewer systems and can be installed and serviced without confined space entry. SmartCover provided each utility with an event management platform with localized weather data from the National Oceanic and Atmospheric Administration (NOAA) to rapidly respond to issues before they become environmental, public health and financial emergencies. This system architecture has revolutionized the utility's response, allowing changes in conditions to be monitored in real-time, while reducing the uncertainty around the conditions in the network. Knowing the level trends in the sewers has helped the utilities schedule maintenance when and where it is needed most, and more importantly has been critical in preventing overflow events. SILENT SENTRIES PROTECT ENVIRONMENT The City of San Marcos, TX, treasures the San Marcos River, a spring-fed river winding 75 miles providing a critical habitat for eight endangered species. Further, the region is of significant archaeological interest as one of the oldest continuously inhabited places in North America. Given the river's rich history and central role in the city, its protection is a primary focus. Yet, extreme weather events are making this increasingly difficult. Solution: To preserve the local waterways during extreme weather events, the city installed 10 SmartCover monitors in high risk spots and outflows. Results: Automatic advance notification of blockages has helped the city mitigate SSOs and monitor and report on CSOs, adhering to the Texas Pollutant Discharge Elimination System Small Municipal Separate Storm Sewer (MS4) requirements. SSO MITIGATION SEES IMMEDIATE ROI Heavy rain events contribute to sewer overflows in the City of Arlington, TX, damaging property, the environment and impacting public health. Solution: Installation of 10 SmartCover sensors and rain monitors to measure flow in typical sewer trouble spots. This event-driven system allows staff to react to any blockages and other potential overflow conditions before wastewater backs up into homes and businesses or overflows the system. Results: In the first few months, the City of Arlington was notified of three alarms that helped avoid sanitary sewer overflows-- more than paying for the systems in a short period of time. After a presentation to City Council, the initial deployment was expanded to 60 SmartCover units using NOAA rain data. CLEANING PROGRAM OPTIMIZATION RESULTS IN SAVING 95% San Antonio Water System was facing an EPA Consent Decree with an estimated cost of $1.2 billion. SAWS adopted the EPA's CMOM guidelines and instituted high frequency cleaning for their 110,000 manholes and pipeline segments. Effectively this meant SAWS established a program of cleaning high risk pipes with potential for overflows, and instituted routine cleanings at monthly, bi-monthly, quarterly, semi-annual and annual frequencies. As conscientious sewer operators, SAWS identified 200 high risk sites for regular monthly cleanings – whether the pipes needed cleaning or not. While prudent, the logistics, labor and equipment costs to maintain this level of effort was staggering. Solution: SAWS deployed 200 SmartCover sensors to collect data. SAWS effectively transitioned from a routine, calendar-based cleaning system, to a prescriptive 'as needed' cleaning program when automatically notified of blockages. Results: SAWS has experienced a 95% reduction in cleaning, ZERO SSO incidence and 216 SSO 'saves.' Nearly 1,300 cleanings were scheduled, but only 65 cleanings were identified and performed -- an estimated $1 million in savings. By trusting automated data analysis, the optimized maintenance schedule has led to significant positive benefits for the operator, environment, and communities served. Not only is SAWS effectively reducing wear and tear on pipelines from the routine cleaning, it's also allowing their operators to refocus on other pressing activities. CONCLUSION Operators in the City of San Marcos, City of Arlington and City of San Antonio have successfully turbocharged their collection systems with innovative technology. All cities reported reduced overflows and costs. These 24/7, silent sentries have brought peace of mind knowing sewers are being monitored, data is automatically analyzed and plenty of advance notice will be given.

Storm sewers are designed to safely convey runoff from rainfall events of a certain maximum intensity and/or depth. Depending on when the sewers were designed and built, in many areas of the world it is highly likely that the design storm frequency and intensity has changed, with storms getting more intense and the return interval of storms decreasing as climate change progresses towards higher temperatures. This is resulting in extreme flooding events occurring with increasing frequency and damage. In 2023, floods and flash floods caused around 2.1 billion U.S. dollars' worth of property and crop damage across the United States. Assessing the current and projected intensity and changing frequency of extreme storms is critical for utilities and municipalities to make changes to current sewer collection practices, to prepare for surface storage of flood waters, and to decide on future design standards for stormwater management. There are three aspects to stormwater planning that are not always understood or fully addressed. 1.Current patterns of extreme rainfall have already changed from the assumptions used in past studies. This requires a re-calculation of changes to extreme rainfall frequency and intensity already being experienced. 2.Rainfall intensity and frequency will continue to change in the future due to climate change. Understanding the magnitude of the change, as well as the differences in projected change depending on the storm duration and return interval is critical to preparing for future floods. 3.The challenge of understanding the uncertainty associated with extreme rainfall frequency estimates, both for current and future conditions cannot be underestimated. There is a need to understand the range of projections, as well as to extend the projections beyond the 5- to 10-year return interval often associated with collection system design. The purpose of this presentation is to address all three aspects of stormwater planning and present some tools and approaches to address each challenge. This paper will present: - Three practical methods for updating current extreme rainfall probabilities and making projections of climate induced changes. The approaches present innovative and unique methods of assessing changes for current extreme rainfall as well as projected changes that account for duration and return interval of rainfall events. These techniques have been developed and applied both in the US and abroad, and have been benchmarked against several existing Federal and State projections. - An innovative approach to developing synthetic storms and stochastically generating long precipitation time series that will help explore the full range of potential extreme rainfall events. This method can help better evaluate both current and future projected probabilities of extreme rainfall events. The issue of uncertainty in current and projected extreme rainfall increases the complexity of making stormwater management decisions but is critical for a more complete understanding of flood risk. The presentation will show that a semi-parametric stochastic approach, which generates synthetic storms of varying durations and volumes, allows a better exploration of current and future uncertainty in the estimates of extreme rainfall. It also provides the necessary data to develop annual exceedance probability estimates for return intervals that far exceed the length of rainfall data from rain gauges. This innovative method, developed in the past year, has been applied to projects in Arizona and New Mexico. Understanding flood risk when designing storm sewers can no longer rely on the tried-and-true process of using published estimates of extreme rainfall based on past rain gauge data, or even of NOAA frequency estimates. Climate change and a better understanding of the variability inherent in current data make it critical to broaden our assessments to meet the challenges of climate change and the uncertainties in the rainfall data we use. By exploring the full range of current and projected extreme rainfall and their associated return intervals, better decisions can be made in designing collection system upgrades, as well as to plan for surface conveyance of stormwater to avoid excessive flood damage during extreme rainfall events.

Introduction Greenhouse gases (GHGs) such as methane and carbon dioxide are common byproducts of chemical reactions within collection systems but are less commonly considered by municipalities during sustainability analyses. Understanding the scope of the impact of these GHGs requires an understanding of their relative effects on global warming. The Intergovernmental Panel on Climate Change (IPCC) created the Global Warming Potential (GWP) metric to compare different GHGs via an equivalency to carbon dioxide (CO2e), the reference gas. Methane has a GWP of 28, meaning that it has 28 times the impact on global warming as compared to carbon dioxide. After outlining and studying the theoretical reactions of sulfide generation in wastewater collection systems and calcium nitrate dosing for sulfide prevention, we hypothesize that dosing calcium nitrate for odor and corrosion control significantly reduces the overall impact of GHGs emitted by wastewater within collection systems. Objective In the proposed paper, we will set the groundwork to understand the theoretical mitigation of methane generation resulting from calcium nitrate dosing in US wastewater collection systems, as well as test the theoretical mitigation with a use case in Manatee County, FL. Theoretical Methodology In an untreated collection system, an anaerobic BOD reduction occurs in the wastewater as follows (all reactions assume methanol as carbon source for simplicity and consistency in comparison): SO4= + 4CH3OH → S= + 4H2O + 2CH4 + 2CO2 In a collection system being dosed with calcium nitrate for sulfide prevention, the intent is to drive an anoxic BOD reduction in the wastewater instead of anaerobic, which occurs as follows: 6NO3- + 5CH3OH → 5CO2 + 3N2 + 7H2O + 6OH- While more CO2 is generated in this reaction versus the anaerobic reaction, no methane is produced. Based on the comparison of these reactions and the GWP of methane, for every 1 lb of sulfide prevented, 25.25 lbs of net CO2e is prevented. Assuming that all GHGs are fully released from the wastewater into the atmosphere, we calculate that a maximum of 11.83 lbs CO2e can be prevented per gallon of 3.5 lb NO3-O/gal solution dosed into collection systems as part of an odor prevention program. In fiscal year 2021, theoretically a maximum of 71,887 metric tons of CO2e could be prevented as a result of all the chemical shipped to customers in the US by Evoqua for use in odor prevention. While it is recognized that a municipality choosing an odor prevention program will be incurring additional GHG emissions via transportation, manufacturing, provision of service, etc, the analysis of the use case study will focus explicitly on changes in GHG emissions specifically related to the theoretical reactions described above in relation to calcium nitrate dosing into the collection system. Application Manatee County Utilities (MCU) operates an expansive collection system involving over 800 lift stations (LS) with many long retention time force mains. The collection system conveys over 22 million gallons per day (MGD) of flow across three service areas to a corresponding wastewater reclamation facility for each service area. To significantly reduce corrosive conditions, MCU set a target atmospheric hydrogen sulfide (H2S) control objective of 20 ppm average and 50 ppm peak. MCU utilizes multiple solutions within their program, including calcium nitrate and pH shift technologies, to achieve these goals. For additional knowledge and to establish a baseline, we decided to also test the methane mitigation from dosing other chemicals by testing sites treated with magnesium hydroxide and calcium hydroxide. Four portions of the collection system were selected for sample testing. Two portions, N4B force main to N1B LS and Greenbrook 2 force main to Lakewood Ranch Riverwalk LS, are treated with calcium nitrate. Another section, Pope Road Master LS, receives flow treated with magnesium hydroxide. The final section, Tara 20 LS, receives flow treated with calcium hydroxide. A portable H2S gas monitor was deployed at each injection point and each control point to log continuous sulfide measurements. Grab samples were taken for dissolved sulfides, pH, temperature using gas detector tubes and a calibrated Hach portable pH probe. Gas samples were collected from the headspace of the wet wells using tedlar bags and CO2/CH4 concentrations analyzed via GC/MS by a certified third-party lab. Samples were collected at periodic intervals based on route efficiency and record keeping. Results and Discussion From six sample sets taken from the N4B force main to N1B LS, five showed a decrease in methane concentration from the injection point to the calcium nitrate-treated control point, with an average decrease in methane concentration of 38%. Half the samples showed an increase in CO2 emissions at the control point. Similarly, five of the six sample sets collected at the Greenbrook 2 force main to Lakewood Ranch Riverwalk LS saw a decrease in methane concentration with an average decrease of 13%. CO2 results from Greenbrook 2 mostly decreased in concentration, but only by small fractions. More data is needed to draw conclusions regarding CO2 results. Overall, methane was broadly reduced with nitrate treatment, with an average of 24% reduction in methane emissions during nitrate dosing. The CH4 concentrations at Pope Road Master LS treated with magnesium hydroxide were similar to that of the control points treated with calcium nitrate but showed lower CO2 values. The CH4 and CO2 concentrations at Tara 20 LS treated with calcium hydroxide were similar to the results obtained from the control points of N4B force main to N1B LS and Greenbrook 2 force main to Lakewood Ranch Riverwalk LS. This paper will go further into the analysis of the results, discussing outliers, testing challenges, and comparing test results to theoretical assumptions. We will also discuss the immediate and future steps to support the project, such as utilizing a continuous method of data collection for more robust data to decrease standard deviation. Another municipality has expressed interest in continuing the research within their collection system, which will provide more information on methane mitigation regarding different collection system designs, climates, and wastewater characteristics. We will also discuss the long-term sustainability target of evaluating GHG emission impacts from the full life cycle of calcium nitrate dosing for odor control, including manufacturing and transportation impacts. Benefits The theoretical mitigation calculation method would allow any municipality to calculate the methane mitigation they are achieving as a result of their odor control program utilizing calcium nitrate, making it easier to quantify the sustainability benefit of the program and communicate it with their community. As sustainability metrics become more important, including GHG metrics, these calculations can play a critical role in quantifying the overall GHG impact of the wastewater treatment and collection system and providing an additional method of GHG reduction. In the case of Manatee County (the County), the benefits are less theoretical. The County conducted a GHG Audit that was completed in June 2020, and while it took into consideration the wastewater treatment plants and overall utility operations, it did not examine GHG emissions from the collection system. This audit recommended a reduction of nearly 3,000 metric tons of CO2e a year to reach net zero by 2040. Understanding GHG emissions and particularly methane mitigation of the odor prevention program could allow MCU to demonstrate a more robust view of the wastewater contributors towards GHGs for the County as well as provide potential solutions towards the recommended reduction goal through a method that neither party may have considered beforehand. Whether or not wastewater authorities or utilities have their own GHG goals, they can provide benefit to their municipalities that are more likely to have them, as well as build public support through communicating the sustainability impacts of their operations.

Missouri has a strong partner for outreach and education activities. The Missouri Stream Team Program is a working partnership of citizens who are concerned about Missouri streams and two state agencies. Funded and staffed by the Missouri Department of Natural Resources and the Missouri Department of Conservation, the Stream Team Program has been around for over thirty years and has thousands of volunteers around the state. The Stream Team Program provides an opportunity for all citizens to get involved in water conservation through clean ups, water quality monitoring, storm drain stenciling, watershed restorations, and more. The program is citizen-based with program staff providing training, supplies, and expertise at no charge to help with stream projects and information. These activities are a natural fit to help MS4s reach their education and outreach requirements. Not only does the Stream Team Program help many Missouri MS4s with education and outreach, but also benefits many other elements in MS4 programs and increases resident awareness of stormwater issues.

Purpose: Hillsborough County (County), Florida, has experienced strong population growth in recent years, which has increased the demand on their existing wastewater collection system. To maximize the capacity of the collection system, the County started a comprehensive mainline cured in place (CIP) lining program. After CIP lining the mainlines, the County continued their infrastructure investigation and conducted a post CIP lining sewer inspection and rehabilitation program focused on infiltration reduction. The purpose of the post CIP program was to identify the source of lateral infiltration, public or private, and rehabilitate laterals up to the property line. Benefits of Presentation: Infiltration reduction minimizes increased wastewater flows experienced when the groundwater table is high and following wet weather events, while reducing the opportunity of sanitary sewer overflows. For gravity mainlines, infiltration is traditionally identified through the completion of Sewer System Evaluation Surveys (SSES) that include manhole inspections, flow monitoring, closed circuit television (CCTV) inspections, smoke testing and dye water testing. These assessment technologies quickly identify areas susceptible to inflow and infiltration (I/I). To identify individual laterals that were leaking post CIP lining, Electro Scan's Focused Electrode Leak Location technology (FELL) was used in combination with traditional lateral CCTV conducted in compliance with National Association of Sanitary Sewer Survey Companies (NASSCO) Lateral Assessment Certification Program (LACP) guidelines. Benefit 1 The presentation will benefit the industry by providing post CIP lining condition assessment results indicating that only lining gravity sewer mains will not reduce infiltration entering the system if tap connections and defective laterals are not sealed. Results of the investigation indicate that a comprehensive CIP lining program in a high I/I area should include the sealing of tap connections and lateral lines to the property line or cleanout. Additionally, the presentation will explain how newer technologies such as FELL can be incorporated into traditional SSES investigations to identify I/I. Benefit 2 This presentation will benefit the industry by identifying construction issues related to the repair and rehabilitation of tap connections and lateral lines utilizing chemical injection grout and full wrap CIP lateral liners. For example, Full Circle Lateral Repair Liners (FCLRL) that extended 3 feet from the mainline lateral tap connection do not require the installation of a cleanout; however, FCLRL repairs that extend more than three (3) feet require the installation of a cleanout to facilitate installation of the liner system. Benefit 3 To track the progress of this project and support the County's growing asset management program, the County developed a GIS asset registry to capture lateral tap connection points, lateral lines, and cleanouts. This presentation will explain how a GIS application was developed to collect locations of lateral line attribute data, and repair and rehabilitation information in real time. Status of Completion: As of 12/5/2023, the total project is approximately 70 percent complete. All FELL work is complete, 95 percent of the CCTV inspection work is complete, and approximately 30 of the lateral repair and rehabilitation work is complete. All construction work is scheduled to be completed in May of 2023. Conclusion: The County began post Cured in Place lining investigation work to address ongoing infiltration issues by utilizing the innovative FELL technology to identify leaking laterals in Hillsborough County's Clair Mel Area. Results of the FELL study indicated 25 percent of the sewer mains previously lined had laterals that were contributing infiltration to the system. Based on FELL infiltration rates traditional CCTV lateral inspections work was completed, which visually confirmed the presence of infiltration identified by the FELL technology. Based on CCTV inspection results, 53 percent of the lateral defects were located on the public side of the lateral and that the infiltration could be addressed by chemical injection grouting or a structural CIP liner. Overall, laterals are a significant source of infiltration entering the wastewater collection system. By sealing tap connections and lateral lines the amount of infiltration entering the system can be reduced which will maximize the capacity of the system and increase the useful life of aging infrastructure.

If performance data is provided to decision makers it often comes from manufacturers. Much of this data is derived from reputable sources such as the New Jersey Department of Environmental Protection (NJDEP) program, the Washington Department of Ecology Technology Assessment Protocol Ecology (TAPE) program, the International Best Management Practice Database (IBMPDB) or the Canadian Environmental Technology Verification (ETV) website but it is difficult for many decision makers to navigate these sources to confirm the data. NJDEP and Canada ETV both have lab data, but it is presented in different ways and the results do not always agree. TAPE has field data. The IBMPDB contains every kind of data but it is not curated so the quality of the data is not assured. The presentation will provide an update on activities aimed to make assessing performance data easier. It will also describe efforts underway to translate existing region verification programs into a national program, to simplify the job of choosing a stormwater control measure (SCM) A new national source of quality assured information, the Stormwater Testing and Evaluation of Products and Practices (STEPP) program, is leveraging resources from several different organizations in order to improve the way data is produced and reported going forward. STEPP, which was initiated by WEF and now led by the National Municipal Stormwater Alliance (NMSA), will provide stormwater managers with tools for evaluating performance of SCMs and guidance on how to use the tools. The initial focus will be on high priority pollutants of interest such as sediment, trash and plastics, and nutrients, but the vision is to expand the program in the future to include additional pollutants as well as including both proprietary products (manufactured treatment devices, or MTDs) as well as public domain practices, including green infrastructure. The presentation describes the STEPP program, how it is organized and how end users can take advantage of it. 2021 also saw the formation of a new ASTM Committee, E64 Stormwater Control Measures. This is a significant step for the industry, ASTM does not form new committees very often. Prior to this change all stormwater standards were developed by a subcommittee, C27.70 under the committee C27 Precast Concrete. This structure hindered effective standards development and that helped lead to the change. The new Committee has 4 subcommittees that includes Lab Evaluation, Field Evaluation, Apparatus and Research Processes, and Non-point Sources. These subcommittees are currently developing several standards and three new standards have been published so far this year. Additional subcommittees will be added as the committee evolves. This presentation will discuss an overview of the ASTM process and how it is relevant to the stormwater industry. It will also introduce the new standards and describe how the current ASTM work relates to STEPP.

Purpose Today many large utilities use hydraulic models to analyze system performance, but what about the future? You can use population projections to forecast regional growth in your model to get your base flow conditions. What about your rainfall? Are you using today's rainfall, maybe Atlas 14 from NOAA, to run simulations? That may be relevant for your current model, but what about the future? As climate change continues to occur, adjustments to the rainfall time series are also needed. This paper goes over how to update your hydrologic model with climate change so your rainfall events keep in step with any base flow changes as you model your system for future conditions. Benefits Planning for the future by using a hydraulic model is good practice to determine if your system can meet the demands of tomorrow. In the Hampton Roads region of southeastern Virginia, the local Planning District takes the US Census and works with each jurisdiction to determine growth in the area for the next 25 years. Planning for population changes is only half of the model equation. Rainfall also has an impact on system performance. As climate change occurs, the 10-year storm event that was used to estimate inflow and infiltration (RDII) into the collection system needs to be updated to capture the increase in rainfall intensity. That 5.6-inch rainfall event today could be a 6.8-inch event in 2050. If you are making upgrades to your system to overcome RDII challenges that exist today, will those improvements stand up to the more intense storms in the future? Status The Mid-Atlantic Regional Integrated Sciences and Assessments (MARISA) is a partnership with NOAA that has developed Intensity Duration Frequency (IDF) curve change factors for the mid-Atlantic region of the US. This work is presumed to be the basis of the NOAA update to the IDF curves that will become Atlas 15 and includes forward looking climate change impacts to rainfall across the US. HRSD has completed the creation of a future rainfall storm event using the local MARISA change factor. HRSD has also completed the creation of future base flows for half of the Service Area to setup the process for expanding the task to the remaining parts of the system. Running the model with the updated rainfall and population forecast for 2050 has shown a significant increase in flow. These modeled increased flows may require system improvements be programmed in the capital improvement plan. Conclusion As climate change continues to happen, planning for the future with today's budgets is more important than ever. While you can plan for growth - X acres of vacant land = Y number of new homes, planning for changes in rain intensity 25+ years from now is just as important. The system you plan today to handle a 10 year rainfall may only be a system capable of handling a 5 year event in the future. Incorporating climate change impacts to rainfall projection into your model along with population projections will provide insight to the limitations of your system and help you prepare your system for the future.

Municipal wastewater treatment plants (WWTPs) generate and emit greenhouse gases (GHG) throughout the plant via a number of activities and operations such as pumping, aeration, mixing, and sludge dewatering and digestion. As part of the collective efforts to achieve a 2050 'net-zero' emission goal, public utilities such as New York City, City of San Francisco (CA), City of Edmonton (Alberta), City of Calgary (Alberta) and Salt Lake City (UT) have started including quantitative sustainability indices as important factors to be evaluated when major capital improvements and O&M modifications are being planned for their water infrastructures. GHG emissions is one important sustainability index. In Canada, GHG emissions from major WWTPs are required to be reported to Environment and Climate Change Canada. A typical WWTP produces three major types of GHG: carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), both directly and indirectly. Direct GHG emissions occur at the site due to fuel consumption and the physical, chemical, and biological treatment processes. Those emissions are fugitive, heterogenous, and time-varying. Currently, three approaches are available for estimating GHG emissions from WWTPs. The first approach uses 'emission factors', such as the IPCC database, to estimate the rate at which a pollutant is released into the atmosphere (or captured) as a result of specific process activities. The second approach involves 'engineering principles and judgement' to estimate emissions based on engineering principles and judgment, using knowledge of the chemical and physical processes involved. Neither the first nor the second approach involves direct measurements. Rather, empirical coefficients are assumed which, often times, are not representative of the actual emissions at specific treatment facilities. The third approach may utilize emission monitoring systems such as the flux chamber method or the tracer method, which unfortunately are all based on point sampling, unable to capture the spatial and temporal heterogeneity of the GHG emissions at WWTPs. Due to the lack of monitoring method, so far, water utilities still rely on using the first two approaches for estimating their GHG emissions. Therefore, a robust field measurement approach is needed that is capable of capturing the dynamic, fugitive emissions at WWTPs. To achieve this, we have developed a hybrid method integrating the long range open-path Optical Remote Sensing (ORS) technology and inverse Dispersion Modeling (iDM) to continuously quantify GHG emissions from the wastewater treatment facilities on a real-time basis. The ORS instrument used in the field campaign consisted of an open-path tunable diode laser spectroscopy (OP-TDL) for CH4, a CO2 sensor, a portable meteorological station and 3-D sonic anemometer to record temperature, air pressure, relative humidity, and wind vector, and an open-path fourier transform infrared (OP-FTIR) for N2O. Both the OP-TDL and OP-FTIR scanned along multipaths to capture the 'big picture' of GHG plumes for dispersion model input for emission estimation. Backward Lagrange Stochastic model (bLS) was used to estimate the methane emission rate in real time. The system was first applied in the Bonnybrook WWTP, with an average daily flow of 324 million litre per day, located in Calgary Canada. Field measurements were conducted in autumn 2021, and spring of 2022. Signals were continuously captured and inverted to calculate the path-integrated concentrations of GHGs, with which the iDM model calculates the emission rates. The measured emission rate for methane ranged from 64-97 kg/hr, with the corresponding emission factor of 0.04-0.06 kgCH4/kgBOD5. For carbon dioxide, the measured emission was averaged at 0.29 ton/yr. Seasonal variations have been noticed. The team is currently working on calibrating a BioWin process model for simulating/predicting GHG emissions using the field measured emission data. Additional field measurements are also planned at a WWTP located in southeast US. This presentation will describe the newly developed ORS-iDS methodology and present the detailed results of continuous measurement from the field campaigns conducted during different seasons. The site-specific emission factors (EFs) developed based on the measurements have been compared with the literature and the IPCC values, which will also be presented to show the inaccuracy of using empirical, non-site specific emission factors. The diurnal and daily variation of emissions will also be characterized and presented.