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OVERVIEW The number of communities in the United States that have established stormwater utilities continues to experience steady growth. As stormwater management increases in complexity, localities are realizing that a dedicated funding source and equitable recovery of costs from within the community are essential for sustainable management of stormwater. Since the 90's, the City of St. Petersburg, Florida (City) has maintained a stormwater utility with revenues generated from stormwater user fees, based upon the amount of impervious surface area measured on each utility customer's parcel, The City has used a 'one-size-fits-all' approach to charging residential customers for stormwater service since its inception. While charging the same fee for all residential parcels has limited the complexity and administration, key stakeholders within the City expressed concern over the fairness and equity of the approach. At the same time, City Council was asking for ways to incentivize green infrastructure to reduce the volume of stormwater entering Tampa Bay. Stantec assisted with the evolution of the City's stormwater utility by creating a statistically sound tiered rate structure for residential customers thereby increasing equity. A menu of green infrastructure options based on a cost of service analysis was created to address the Council's desire to offer a robust credit and incentive program. Since transparency and fairness were a priority for City Council, Stantec helped develop a Stormwater Review and Appeals Portal to allow customers to review impervious area and billing tier in advance of rate adoption. This was a successful collaboration between Stantec and the City which resulted in adoption of a new rate structure and credit policies. This session will highlight the innovative solutions developed to create a transparent, equitable recovery of increasing stormwater management costs and provide insight into how to successfully engage citizens in the process. BACKGROUND There are several challenges that precipitated this comprehensive review of the City's current stormwater fee approach and underlying data: (1) impervious area measurements were mostly collected in 1989 and were not representative of current conditions; (2) revenue requirements increased due to CIPs needed to address flooding and water quality issues; (3) current flat rate fee structure for residential properties reduces equity between residential parcels with large variation of impervious area; and 4) Non-Single Family Residential parcels were charged on their impervious surface area measurement. The City outlined the following key objectives: 1) Digitally map impervious area for all parcels in the City limits to establish a master Geographical Information System (GIS) and analyze and calculate area; 2) Revenue Sufficiency Analysis including a ten-year financial management program; 3) Cost of Service Analysis to allow development of new rates by customer class; 4) Develop a tiered rate structure and update fee calculation methodology; 5) Integrate utility billing system with updated impervious area; and 6) Update the Stormwater Mitigation Credit Program to recognize onsite stormwater management systems and incentivize green infrastructure. IMPERVIOUS AREA DEVELOPMENT Prior to developing a more equitable rate structure, implementation of City-wide Single-Family Residential Parcel's (SFRP) impervious area data by parcel was needed. Impervious surface area for non-SFRP was based on measurements calculated in 1989 (in most cases). Stantec utilized existing high-resolution aerial imagery and GIS image classification techniques to create a geodatabase with an estimate of current impervious area by parcel for the City limits. Stantec explored a modernization of the SFRP fee structure that will serve to enhance equity by recognizing impervious area differentials across the single-family residential parcels. REVENUE SUFFICIENCY ANALYSIS AND COST OF SERVICE Stantec performed a detailed revenue sufficiency analysis (RSA) to evaluate the sufficiency of current stormwater rate revenues over a multi-year projection period, and provided the basis for a plan of annual stormwater rate revenue adjustments necessary to satisfy all financial requirements identified during the projection period from Fiscal Year 2020 through FY 2029, including: 1) Operating and maintenance costs; 2) Capital improvement program costs; 3) Existing and new debt service expenses and corresponding net income to debt service coverage ratios; and 4) Adequate operating reserves. The City is anticipating $2 million in borrowing in Fiscal Year 2020 with additional debt needed in future years to support the capital needs. As such, the RSA identified the need for an increase in stormwater revenues of 9.09% in FY 2020 to satisfy the identified cost of service. The detailed cost of service and revenue requirement results from the RSA were used as the basis of the stormwater fee and credit/incentive programs calculated. FEE STRUCTURE RECOMMENDATIONS Two separate fee structures were recommended for SFRP and Non-SFRP based upon the distribution of impervious area. A tiered fee structure was recommended for SFRP which provided simplicity, while recognizing impervious area differentials. See Figure 1 for a distribution of tier breakpoints. Tiers allow the City to recognize differentials in SFRP impervious area that are of statistical importance and provide administratively efficient price signals across more than 75,000 individual parcels. A four-tier configuration was created that conforms to the underlying distribution of impervious area, while accomplishing the enhancement of equity in this customer class over the current fee structure. Configuring the tier breakpoints based on statistical distribution ensures that the tier break points fit the underlying property data and are not arbitrary and capricious. A parcel-specific fee structure is recommended for Non-SFRP, based on the actual measured impervious area per parcel expressed in terms of SFU. This approach ensures that each parcel's unique impervious footprint is accounted for and the fee levied is proportional, given the wide array of parcel configurations in this customer class. CREDIT AND INCENTIVE PROGRAM A review of the City's existing credit program was performed to identify opportunities to encourage installation of green infrastructure. To determine the appropriate monetary value of the stormwater fee credit or incentive, it was first necessary to estimate the reduced costs incurred by the City as a result of the property owner's on-site management activities. Stantec performed a cost of service analysis to determine those costs that are incurred regardless of the use of and contributions to the stormwater system (often termed base costs) and those that are related directly to stormwater contributions (often termed quality and quantity costs). The City decided to update their policy by offering credits for stormwater management systems and parcels that discharge directly to tidal water based on the percentage reduction estimated in the cost of service analysis. A stormwater incentive is a one-time rebate towards the purchase and installation of qualifying green infrastructure that will provide an annual benefit to the City's stormwater management utility over the life of the infrastructure. The values of the incentives were developed based on the potential reduction in costs associated with reduced stormwater contributions from parcels implementing the control activities and are outlined in Figure 2. LESSONS LEARNED FROM CUSTOMER ENGAGEMENT Once the tiered rate structure was developed based upon the new impervious area data and the revenue requirements, extensive public outreach was performed by the City to inform the public about the new tiered system, share ways property owners could review their impervious area, and address concerns regarding the new methodology before new rates would become effective on October 1, 2019. Stantec and the City designed a Web Portal for citizens to easily review their impervious area, see frequently asked questions and submit an appeal, comment or question. See Figures 3 and 4 for examples of the Web Portal functionality. The ArcGIS based Portal was linked directly to the parcel for City research and response. We learned the stormwater fee structure needs to not only be easy for the community to administer, but more importantly, easy for the community to understand.

INTRODUCTION Many communities are seeking ways to meet stormwater management goals to maximize positive environmental, economic, and social outcomes. Moreover, many of the traditional 'low-hanging fruit' projects that support these efforts are no longer available. Communities are now looking to optimize their existing infrastructure to deliver better outcomes, without solely relying on extensive retrofits or building new stormwater systems (Mullapudi et al., 2018). One example of such a community is the City of Atlanta, Georgia. Like many cities, Atlanta is challenged by a growing population using more resources, aging stormwater infrastructure, urban flooding, and the increasing frequency and intensity of extreme storm events. The City of Atlanta Department of Watershed Management (DWM) addresses these challenges in a number of ways, one of which is to optimize existing stormwater infrastructure to achieve better environmental outcomes. Dean Rusk Park (Figure 1) is one example in Atlanta. Dean Rusk Park is an urban park in Southwest Atlanta, with an 8,590 cubic meter (2.3 MG) stormwater detention pond serving a 38 hectare (94 acre) drainage area. Among the challenges at Dean Rusk Park is undersized downstream conveyance infrastructure, which experiences an increased flood risk during large storm events. To mitigate the risk of downstream flooding, Atlanta DWM implemented continuous monitoring and adaptive control (CMAC) technology at Dean Rusk Park Pond. CMAC uses data from field-deployed sensors (e.g., water level sensors) and the local weather forecast to automatically control stormwater release rates in real-time and better prepare for and respond to precipitation events (Roman et al., 2017). The primary objective of CMAC at Dean Rusk Park Pond is to predictively discharge water before storm events to create additional storage capacity in the pond, thereby reducing the rate and volume of wet weather discharge. CMAC is being implemented in phases. The first phase of the project occurred in September 2018 when a communications and control panel, water level sensor, and rain gauge were deployed on site. This phase also included virtually deployment of automated control logic, in which control decisions (e.g., [i]drawdown the pond in advance of storms[/i]) are simulated to better understand the result of a particular control regime on the Pond. Notably, the data collected during this phase served a critical role in the design of other enhancements to Dean Rusk Park. The second phase includes installing the actuated butterfly valve on the Pond's outlet control structure. The valve will be connected to the on-site control panel, and automatically regulate outflow from the Pond in real-time to prepare for and respond to storm events. This phase is expected to be completed prior to the end of 2019. METHODOLOGY, RESULTS, AND CONCLUSION To evaluate the proposed control logic for reducing wet weather discharge at Dean Rusk Park Pond, the researchers have collected water level and precipitation data since October 2018. Water level data, in context with a stage-storage relationship and a stage-discharge relationship, was used as an input to a hydraulic model to estimate discharge and inflow over the course of one year. Inflow was then calibrated using on-site precipitation data in context with the approximate contributing drainage area. To compare the proposed control logic to the traditional passive stormwater pond, wet weather discharge rate and volume were evaluated for both the observed passive pond and the simulated pond with adaptive controls. The comparison methodology can be found in Marchese et al., 2018. The researchers found that by simulating pre-event drawdown up to 25.4 cm (12 in) below the permanent pool, and targeting zero discharge during wet weather, the tested control logic at Dean Rusk Park Pond is able to reduce wet weather discharge rate and volume for a range of storm events. One example is seen in the evaluation of a precipitation event that occurred on November 12-14, 2018, in which back-to-back storms resulted in a total of 10.2 cm (4.0 in) of precipitation (Figure 2). The observed passive pond at Dean Rusk Park discharged peak flow at approximately 113 liters per second (4.0 cfs), whereas the simulated CMAC pond only discharged at a maximum of 28 liters per second (1.0 cfs). Similarly, the observed passive pond captured approximately 34% of the wet weather inflow volume, and the simulated controlled pond captured 74% of the inflow volume for this event. Figure 2 was generated using observed data from the existing passive pond and hydraulically simulated performance for the adaptively- controlled pond. In addition to enhancing the hydraulic performance of Dean Rusk Park Pond, the City of Atlanta DWM intends to evaluate and utilize adaptive control technology to improve stormwater management across their watersheds. This solution can be integrated into the larger stormwater management effort in Atlanta, which includes empowering data-driven decisions, maximizing the benefit provided by public resources and improving natural resilience throughout the community.

Background The Northeast Ohio Regional Sewer District's Regional Stormwater Management Program (RSMP) was initiated in 2013 to address flooding, erosion, and water-quality issues across community boundaries. The RSMP is the basis for managing the Regional Stormwater System (RSS; Figure 1), which includes culverts and regional storm sewers, streams, in-line detention basins, and ponds and lakes receiving drainage from an area greater than 300 acres. When functioning properly, these assets manage, clean, and convey stormwater runoff and natural drainage within the District's 347 square mile service area (Figure 2). Decades of deferred maintenance, poorly-planned development, and increases in impervious surfaces have negatively impacted RSS function and quality. The District manages and improves the RSS through the RSMP. Specifically, the District completes watershed master plans, hydrologic and hydraulic modeling, data management, inspection, maintenance, monitoring, financing, design, and construction projects. Additionally, the District provides customers access to technical support and resources. Over the long-term, these efforts will help to optimize RSS function, thereby improving water quality, mitigating the effects of flooding, and reducing stormwater-induced erosion. The District's Stormwater Construction Plan (SCP) is part of the RSMP, and it guides the implementation of stormwater system improvements. Typical projects on the SCP include stream restoration, conveyance improvements in culverts, bank stabilization, basin improvements, and general maintenance of the RSS. Challenge Each year the District completes efforts to prioritize projects in the SCP and to formalize a budget request for the following year's program. The original process was modeled after the planning process used for wastewater and collection system infrastructure. It presented three primary challenges to the long-term planning for the RSMP: -- Inconsistent scoring: Four separate groups within the District's Watershed Programs Department manage and implement the RSMP. The responsibilities for tracking and reviewing information from each group was not streamlined, which often complicated the review process and scoring results. Additionally, project scores were not well distributed. -- Indirect connection to RSMP goals. The original framework used a Business Risk Exposure (BRE) tool. The BRE scoring was based on the risk of not completing the project, where the probability of failure accounted for 50% of the score. The BRE tool did not directly account for program priorities of addressing flooding, erosion, and water quality issues. -- Overlooked existing data. The scoring process did not incorporate valuable sources of new data generated from stormwater master plans, asset condition inspections, communication with customers, and maintenance. Objective The District addressed the three challenges with the prioritization process and focused on developing an improved framework for maintaining a long-range SCP. Specific objectives included: -- Establish consistency among projects in terms of evaluation, cost estimating, scoring, and prioritization criteria; -- Consolidate and consult existing data for the annual SCP planning cycle; -- Improve tools for project nomination and scheduling processes; and, -- Develop tools to visually explain the implementation status of the SCP. Approach The effort was organized in two phases. The first phase included a comprehensive review of the program, focusing on nomination forms and procedures, and observing tools and interactions during annual meetings. This provided an understanding of data sources and inputs, metrics, workflows, and tools used to develop the SCP. Additionally, this phase included review of the distribution of scoring results to identify deficiencies in evaluation criteria, and screening other stormwater management programs similar to the District's RSMP. The second phase focused on process improvement, including a new project tracking template and a revised scoring tool. The tracking template was an online SharePoint Project Nomination Form (Figure 3) completed in a web browser. The form includes details related to project background, inspection and maintenance history, results of field observations, a summary of asset condition and risks, project costs, and documentation of coordination with customers. Responsibility for entering project information is shared among internal staff from each of the four groups within the Department. The forms are structured to be continuously updated, and each section of the form allows staff to provide a recommendation for the project. The revised scoring tool was developed based on the program goals and data. It includes six separate scoring factors (Figure 4) to evaluate a project and is directly related to the information contained in the SharePoint Project Nomination Form. The scoring factors align to components of the District's RSMP, performance of RSS assets, and regional considerations. It is based on the anticipated benefits of the project rather than the risk of not completing it, and it prioritizes projects that meet RSMP and asset management goals, assigning higher scores to projects that provide Regional Benefits -- for example: system resiliency, co-benefits, and distribution in the service area. The new scoring tool (Table 1) was applied to a representative set of 20 projects, and scores were compared to those from the original BRE scoring tool to identify changes in scores and prioritization. The scoring metrics, values, and weights were reviewed and refined during workshops with District staff. This collaboration helped build support for the refined process. Results The process improvement recommendations were applied to the 2019 and 2020 SCP planning cycle, and results were positive. Key outcomes included the following: -- Improved communication during annual nomination meetings. Distributing responsibility for completing the Project Nomination Forms required that at least one representative from each group in the District's Department input and manage project data. This helped to improve communication, increase the efficiency of annual project validation meetings, and reduce uncertainty in scoring and prioritization. -- Integrated existing RSMP data. The scoring criteria rely on data generated from ongoing data collection efforts and address the observed deficiencies of the former BRE scoring tool. -- Scoring prioritizes RSMP goals and regional impact. Aligning the scoring tool to the goals of the RSMP prioritized projects that are anticipated to reduce flooding and erosion and improve water quality. The use of weighting in the scoring values distributed the scores. -- Visual tools elegantly convey information about the Stormwater Construction Plan Microsoft PowerBI software was used to demonstrate how program data can be tracked and visualized across watersheds and communities, and in terms of project phase, schedule, and costs (Figure 5).

San Diego's Public Utilities, Wastewater Collection Division (City) maintains 3,050 miles of gravity sewer. More than 15-years ago, their CMOM program was implemented to reduce dry-weather SSOs employing the 'best practice' (1) of system-wide cleaning every five years and trouble-spot, high frequency cleaning. By 2014, a 90% SSO reduction to 0.93/100 miles was achieved. These exceptional results came with corresponding cost increases including: --

The DC Clean Rivers Project is DC Water's massive infrastructure program, including green infrastructure (GI), to reduce combined sewer overflows (CSOs) into the District's waterways. DC Water's GI program involves the construction of innovative GI technologies that include bioretention (rain gardens) in planter strips and curb extensions, permeable pavement on streets and alleys, GI streetscapes and parks, and downspout disconnection (including rain barrels). To date, DC Water has constructed over 360 GI facilities and enrolled approximately 300 homes in the downspout disconnection program. This extensive construction has required outreach to over 8,400 homes and businesses including over 100 meetings with the community and distribution of over 30,000 door-to-door flyers. Construction projects in an urban environment present unique challenges and constraints. Unlike many utility projects that impact one specific area, DC Water's construction of GI occurred in over 300 separate locations, including alleys and planter strips, areas directly adjacent to homes and businesses. Facilities are located throughout vastly different neighborhoods that vary socioeconomically and have distinct neighborhood, council, and civic association representation. The success of DC Water's GI program depends, to a great degree, upon community education, awareness and active communication during the implementation of its GI program. Ensuring that the public is adequately informed of construction and the associated impacts is not only essential to public acceptance of GI, but is critical to keeping the project on time and budget. Inadequate outreach can result in public complaints and the resulting local government intervention can cause delays and even work stoppages or scope changes. DC Water's outreach program is a strategic approach for educating and engaging residents, property owners, key stakeholders, and the general public to promote and facilitate installation of GI on the public right-of-way and private property. A comprehensive public outreach program was developed to ensure adequate communication during every stage, from design to construction and long-term maintenance. DC Water's public outreach and engagement efforts for the GI program include: 1) Hosting a GI program-specific webpage with links to each GI project 2) Distributing project-specific factsheets/mailers/door hangers/newsletters 3) Informing the Mayor's Office, Council, and local neighborhood representatives 4) Presenting at community meetings 5) Hosting events (coffee corners, kick-off celebrations, etc.) 6) Participating in community events/farmers markets/schools/festivals/etc. 7) Providing face-to-face communication through canvassers 8) Advertisements on social media/press releases/local newspapers 9) Promotional items such as water bottles, coloring books, grocery bags, etc. 10) Utilizing local bloggers, Citizens Associations, and listservs to disseminate information 11) Developing innovative educational videos and infographics 12) Multiple points of contact (outreach manager's direct phone number and email address, 24/7 project hotlines, dedicated project email addresses) 13) Informational signage at construction sites/Facility ID signage/Business Open Signage --

Like many utilities and municipalities faced with the challenge of implementing and maintaining hundreds of green infrastructure (GI) facilities, DC Water has made significant inroads towards streamlining and standardizing its GI designs and permitting process. In the District of Columbia, District agencies had been designing and constructing GI with custom, site-specific designs. These facilities came with high design and construction costs, inefficiencies, and inconsistent designs/aesthetics, especially across the various agencies. A significant portion of the project cost for relatively small and low-cost GI facilities is often related to the design. Additionally, because DC Water sits outside the District government, GI costs are further increased due to the need to work with agencies to permit each custom-designed facility and rehabilitate surrounding portions of roadways and alleys once construction is complete. There exists significant opportunity to reduce costs through improved agency coordination and through standard design and construction. For public infrastructure, standard designs are used to maximize construction efficiency for hardscape such as sidewalks and roads. Beyond reducing design costs, standardization improves construction efficiency by creating consistent construction requirements for each facility on every project and a more uniform appearance of facilities for the community to become accustomed to. In early 2017, DC Water, in collaboration with District agencies, developed a standard design process for permeable alleyways using GIS and standard construction details. Field tablets were used to quickly evaluate potential sites, where the efficiencies of a standardized approach would be realized. Working closely with permitting agencies, DC Water updated its design details to accommodate both a streamlined permitting process and the issuance of a blanket permit as well as creating a simplified design package for the Contractors to bid on. This process was further refined during the implementation of the Districts AlleyPalooza program. The partnership between DC Water and DDOT provided the opportunity to expand our standardization tool box to include simplified specifications, erosion and sediment control measures, MOT, and testing protocols. DC Water realized that implementing standard designs in a diverse, highly urbanized environment also comes with challenges and risks, and needed to remain nimble to account for these challenges, not just through the design process, but also during and after construction. The Potomac River-A and Rock Creek-A projects account for the first two of eight GI projects in the nation's capital, part of its Long-Term Control Plan to reduce combined sewer overflows. Under DC Water's consent decree, modified in 2016, the Authority will design and construct GI facilities to manage 1.2' of rainfall on 498 impervious acres between now and 2030. The Potomac River-A and Rock Creek-A GI projects highlight a myriad examples of variable physical site characteristics which the standard designs had to account for, such as unknown utilities, unclear property lines, buttressing tree roots, unusual street drainage, and degraded areas adjacent to proposed GI. Site verification, basic property line analysis, 360-degree imagery were critical tools for successful siting of standard designs during the design stage. However, DC Water was realistic and understood that undertaking construction of a standardized design in the built environment would require field adjustments to accommodate the unknowns when working in the urban landscape. Prior to construction, DC Water participated in a qualitative risk analysis, creating a risk register to account for these unknowns. A Quantitative Cost Analysis was then prepared to determine the appropriate contingency dollar amount at the 95% Confidence Interval to be carried by DC Water to address the cost impacts of identified risk events should they occur. During construction, the 'one-size-fits-all' installation of a standard design proved to provide the construction efficiencies anticipated. Nonetheless, as green infrastructure was being constructed, performance due to site variabilities became apparent as well as the need for increased maintenance. For example, in finished alleys, the amount of sediment captured within the facility was due to the variability within the physical characteristics of the properties served by the alley. These characteristics included parking pad materials (concrete, stone, dirt), property interface with the alley (grass, landscape-wall with weep holes, bare dirt) and quantity of roof disconnections directed onto the alley. These elements are not always accounted for in developing a standard design but can cause performance and maintenance issues due to the fluctuation in sediment loading. To mitigate this issue that became apparent during construction, DC Water needed to account for those conditions by quickly developing and implementing an additional feature to solve the issue. Concrete sediment traps upstream of the alley were installed to capture sediment before reaching the permeable areas of the alley. Not only was this utilized to correct the issue in alleys yet to be constructed, but the design needed to be able to be retrofitted in completed alleyways. Post construction monitoring of the facilities began in March 2019 and it was quickly observed that the flow restriction device valves that were installed, began to leak around the seals. These valves were initially tested during the design stage to determine the allowable release of water through the underdrain system back to the combined sewer. Once constructed, functional testing of the facilities proved that the valves were properly sealed and provided the necessary control of water back into the system. However, over time, the valve performance dropped. DC Water reviewed and tested many alternative solutions, and replaced the valves using a plug with orifice. A custom designed installation system was developed to install the plugs in pipes 5' below the surface. Additional lessons learned and innovative solutions will be presented in the final presentation and paper.

Let's Talk Trash: Developing a Scalable Pilot Study for Implementation of Stormwater Control Measures Bethany Bezak, Olivia August Track: E. Post-Construction Control Measures Accumulation of trash in urban watersheds everywhere has threatened waterway health and congested stormwater conveyances causing flooding and reduced system capacity. To address the issue, the California State Water Resources Control Board (SWRCB) adopted what are collectively referred to as 'the Trash Amendments'. The City of San Diego has selected to pursue compliance through the installation, operation, and maintenance of full-capture devices, multi-benefit projects, as well as treatment and institutional controls. Before city-wide installation of full-capture devices, the City is strategically testing and trialing potential devices to determine suitability for implementation. This presentation highlights the development and preliminary results of a full-capture device pilot program designed to be scalable for future City-wide implementation. Although, the case study presented focuses on trash controls, the process for pilot program development and execution can be applied to a variety of post-construction control measures. To ensure effective city-wide roll-out of trash capture devices, the pilot study tested a diversity of devices to comprehensively address City implementation needs. Device evaluation began with the State Water Board's list of over 40 approved full-capture devices and was further narrowed based on suitability for San Diego implementation. Key device information such as adaptability, cost, flow capacity, storage volume, installation procedures, maintenance and access requirements, and lifespan was compiled for comparison of devices. Pilot devices were selected to provide invaluable information needed to enable future scaling of the pilot study results. Based on an analysis of the storm water infrastructure composition, certain devices, such as grate inlet devices, were eliminated from the candidate list based on suitability for municipal application. Additionally, the budgeted trash capture implementation cost was compared to the capital, O&M, reporting, and monitoring costs of trash capture devices. This step mainly disqualified custom and high flow capacity devices, such as in line separators, manhole structures, and end of pipe flow nets as cost-prohibitive. An additional scaling concern was the added maintenance burden of widespread device implementation. Operations and maintenance staff were included in the evaluation process to identify which devices would require excessive labor or equipment to maintain. Currently, O&M regularly inspects and maintains catch basins as part of permit requirements. Therefore, inlet and connector pipe screen devices would be installed into assets the City is currently maintaining. The device selection process illustrated below in Figure 1, ensured that device selection was grounded not only in physical site suitability but also fit into existing City programmatic and maintenance activities. [INSERT DIAGRAM HERE] Figure 1. Trash Capture Pilot Study Device Selection Process In addition, pilot sites were chosen to be representative of the larger application area with standard sizing, configurations, and conditions. Methodical selection of sites allows for uniform data collection and effective comparisons across the pilot study. A process shown in Figure 2, was created to identify sites that would maximize trash removal, but minimize potential operational issues. Therefore, sites within trash priority land uses and with greater historical debris deposition were prioritized for device installation. To facilitate coordination of installation, monitoring, and maintenance of multiple devices, sites were selected within one watershed. Additionally, selected pilot sites were located at least 100 feet away from the Federal Emergency Management Agency (FEMA) flood zones and 2D-modeled flooded areas. Also, to mitigate for the impacts of site-specific conditions such as flooding, vandalism, or excessive trash loading, redundant devices were installed. [INSERT DIAGRAM HERE] Figure 2. Trash Capture Pilot Study Site Selection Process In addition, the pilot study was designed to capture consistent and meaningful data related to trash implementation efforts. The study included standardized and streamlined data collection metrics. Quantitative performance metrics and standardization of qualitative metrics were employed to assess device performance, ease of maintenance, and suitability for implementation. Additionally, data collection metrics and frequencies were developed to comply with the trash implementation monitoring program. Overall, this pilot study represents a comprehensive assessment of stormwater control measures to inform scalable implementation. The study was grounded in meaningful data to ultimately determine device selection and contribute to a greater certainty of compliance and program success.

As green infrastructure projects are rapidly being designed throughout the nation, project owners are trying to also plan for the sustainable operation and maintenance of these facilities to meet project goals into the future. This presentation provides an opportunity to revisit Malibu Legacy Park, an award-winning stormwater detention and reuse, habitat and recreation project located in the coastal California City of Malibu, to share both the successes and insights from lessons learned during over nine years of operations. Malibu Legacy Park was completed and began operating in October 2010. For over nine years, the Legacy Park site has provided compliance with bacteria and nutrient reductions goals while providing a community and environmental amenity for Malibu residents and visitors. Woodard & Curran was hired by the City starting in 2005 to provide support from the early planning and funding stages through design and implementation. The Legacy Park project was envisioned by the City of Malibu as part of a holistic approach to address the bacteria and nutrient total maximum daily loads (TMDLs) affecting the Malibu Creek and Malibu Lagoon. The unique, undeveloped coastal location of project site made the project of high interest to community groups, nongovernmental organizations, and businesses. To meet the needs of the many stakeholders involved, additional objectives were included in the design beyond meeting TMDL compliance and creating a new local water supply. These included preserving open space, developing a community 'central park', creating and restoring native habitats, and maintaining space for community gatherings. Legacy Park's primary park feature is an 8 acre-foot detention pond that captures all wet and dry weather flows from the surrounding 337-acre watershed. The pond serves as stormwater pre-treatment and to equalize flow into the companion 1,400 gallon per minute Civic Center Stormwater Treatment Facility. The Stormwater Treatment Facility provides filtration and disinfection of dry-weather flows and first flush runoff pumped from surrounding storm drains. Taken together, Legacy Park and the Stormwater Treatment Facility have eliminated discharges from the local watershed into Malibu Creek and Malibu Lagoon -- resulting in consistent 100% TMDL compliance. Situated around the detention pond, Legacy Park created five different native coastal habitats highlighted through several public art and education kiosks located along park walking paths. These habitats and other landscaping are irrigated as needed with the stormwater collected on-site. While Legacy Park has been undeniably successful at meeting regulatory and community needs, the story of how the Park was financed, designed and constructed as well as how it is currently operated and maintained provides opportunities to learn from the many lessons taught along the way. Examples of lessons and strategies include the following: 1) Creative financing and funding strategies: The use of public-private partnerships (P3), multiple grants and loans, as well as community donations meant that the project needed to meet several objectives beyond TMDL compliance to ensure a successful project for a variety of funders. Identification of ongoing funding to cover annual operations and maintenance was also an issue to overcome. 2) Balancing multiple goals and uses within one site: Although 15 acres, the siting of facilities and landscaping to meet stormwater quality and supply goals as well as interests in restoring coastal habitat while providing a public amenity for the community meant striking a negotiated balance. 3) Maintaining native landscaping: The reality of using native plants may not match the aesthetic vision of all members of the surrounding community. Further exacerbated by multiple drought years, the City had to develop an irrigation and overall maintenance plan that reflected the habitat while continuing to provide an aesthetic resource for the community. Planting replacements to address other factors, such as salinity issues, were also required. As part of an overall program to improve water quality in Malibu Creek, Malibu Lagoon and Surfrider Beach, the City has been successfully operating Legacy Park while also designing and constructing a companion project focused on capturing, treating and reusing wastewater flows within the Civic Center area of the Malibu Creek Watershed. With the successful opening of the Civic Center Water Treatment Plant in 2018, the City's overall program vision came full circle by providing an additional source of irrigation supply for Legacy Park. In keeping with the theme of the Symposium, the story of Malibu Legacy Park highlights a case study of excellence in sustainable stormwater management, illustrating how integrated planning and multi-benefit project development and implementation can result in long-lasting, high value benefits and sustainable practices.

School districts are one of the largest land managers in every city across the United States. In California alone, more than 130,000 acres are managed by public school districts. These large impervious surfaces present significant challenges to water quality and present prime opportunities to manage stormwater and provide benefits to children and communities. Typically designed for minimal maintenance, the average schoolyard in America today offers little for children's development. These landscapes do not link to current demands for hands-on experiential education, environmental literacy, or project-based learning. San Francisco Public Utilities Commission (SFPUC) staff saw the connection between these impervious surfaces and the potential for greatly improving the community spaces. The team created a partnership between the San Francisco Unified School District (SFUSD) and the SFPUC to implement green infrastructure citywide. 'A Stormwater schoolyard' is a schoolyard that prioritizes multipurpose infrastructure that delivers stormwater performance while enhancing children's learning and play opportunities. These schoolyard projects can manage stormwater while delivering significant co-benefits to students, teachers, and the community. Since the start of the partnership in 2007, there have been over 50 stormwater schoolyard projects implemented across San Francisco. This presentation will cover how SFPUC developed a strong working relationship with SFUSD, challenges and successes in completing demonstration projects, the impact of stormwater management regulations, and how San Francisco is scaling up the partnership to deliver joint capital projects that provide regional stormwater benefits. In 2014, the collaborative team initiated their first large-scale stormwater schoolyard pilot project. Building on the lessons learned from small-scale interventions and stormwater regulation projects, the team set out to create a new path for shared project development, delivery and management. The SFPUC provided the funding for the green infrastructure features and technical assistance. SFUSD provided funding for other schoolyard elements and delivered the project as part of their bond program. In January 2017, the SFPUC and SFUSD hosted a 'Living Schoolyards as Stormwater Infrastructure' week. The team hosted training and design workshops with experts from Europe to optimize the investment's value for stormwater management and watershed health while employing best practices in design for children's learning and play. The presentation will cover exciting design inspirations from Berlin and how they were transformed to fit the American schoolyard model. The RL Stevenson Stormwater Schoolyard Project was the first project to fully test the integration of stormwater schoolyard designs, funding and teams. The project finished construction in August 2018. This presentation will share lessons learned from planning through construction, including lessons learned from integrating the goals of stormwater management in children's environment, cross agency teams, funding and operations and maintenance considerations. The team will also share progress towards their next goal, of scaling up these demonstration projects to the first joint SFPUC-SFUSD capital projects. The team is working on joint use agreements for capital wastewater infrastructure on school property, collecting regional stormwater runoff, and operations and maintenance coordination between agencies. The team will share design alternatives for two selected school sites to serve as the first capital projects.

BACKGROUND El Paso Water Utilities - Public Service Board (EPWater) operates the John T. Hickerson Wastewater Reclamation Facility (JTH WRF) on the northwest side of the City of El Paso, Texas. The JTH WRF is an activated sludge secondary treatment plant with lime stabilization of biosolids, treating between 9 and 10 million gallons per day (MGD) average dry weather flow (ADWF). The plant serves the northwest portion of the City of El Paso, has a treatment capacity of 17.5 MGD, and treats wastewater from commercial, industrial, and residential sources. The plant is bordered by I-10 as well as businesses and open spaces. Residential housing is located a close distance from the plant and plans include additional residential and commercial development along I-10 near the plant. Odor emissions at the JTH WRF are directly related to wastewater characteristics entering the front end of the plant from the collection system. Wastewater entering the JTH WRF is characterized as septic with high levels of dissolved sulfides. Over 90 percent of the flow to JTH WRF is conveyed in a dual force mains from Frontera LS. The approximately 3.5-mile-long Frontera LS dual force mains has three separate lengths of dual 30-, 36-, and 42-inch-diameter lines. The raw wastewater in the force mains produces levels of dissolved sulfides as high as 20 mg/L, which result in a large amount of gas-phase hydrogen sulfide (H2S) in the headworks and throughout the plant; reaching levels greater than 100 parts per million (ppm) at the headworks. JTH WRF ODOR STUDY Objectives: In 2012, EPWater hired Jacobs to assess the current odor situation and prioritize alternatives to reduce offsite odors in support of the positive relationship with the surrounding community. Process Evaluation: Both vapor phase and liquid phase odor control alternatives were considered. Various liquid phase treatment (LPT) technologies were evaluated for improving wastewater characteristics for reducing odor potential and jar testing was conducted where applicable; including the following: Sodium Hypochlorite (oxidant); Nitrate Inhibitor and Alkaline-Enhanced Nitrate Inhibitor; Magnesium Hydroxide (pH adjuster); Alkaline-Enhanced Iron (ferrous chloride precipitant); Oxygenation (Super Oxygenation with super oxygenator cone); Ozonation. During the study phase, a dispersion model was developed for the Super Oxygenation liquid phase treatment (LPT) alternative. Jacobs modeled the before- and after- Super Oxygenation system (or comparable liquid phase treatment) operation modeled results. The odor concentration is expressed as the number of dilutions that were required for one-half of the olfactory panel members to record detection, or detection threshold (DT). It is generally recognized that approximately 0.5 to 1 ppbV of H2S is equivalent to 1 DT. A life cycle cost evaluation between SuperOxygenation and Magnesium Hydroxide resulted in a total project present worth cost of $3,578,000 for the SuperOxygenation System and $9,269,000 for Magnesium Hydroxide. Process Selection: In the final evaluation report, implementing a new Super Oxygenation system at the Frontera LS along with optimization of an existing headworks chemical scrubber at the JTH WRF was recommended. This approach was selected based on both favorable expected offsite odor improvements (as validated by dispersion modeling) and lowest life cycle cost when compared to other alternatives. It should be noted that the Super Oxygenation system will also reduce corrosion within the welded steel force mains as well as reduce odors along the force mains where air relief valves or other leakage sources exist. DESIGN CONSIDERATIONS The goal of a SuperOxygenation System is to add enough oxygen to a force main to maintain aerobic conditions and therefore prevent the formation of sulfides. BOD degrading bacteria consume oxygen at a rate of approximately 10 mg/L/hr. If this demand is not met, the bacteria will use sulfates as an alternative oxygen source and produce sulfides as a by-product. SuperOxygenation Systems are designed to satisfy the oxygen demand of the bacteria and therefore prevent them from producing sulfides. Other factors that have to be considered for the design of a SuperOxygenation System are: --