Currents 2024: Volume 1: XBAT-A Game Changer for Water Treatment : simplebooklet.com

2Welcome to the first issue of Currents in 2024! In our feature story, we introduce a new, groundbreaking technology that can be used for treatment of salinity and TOC without high-pressure membranes. It’s called Ion Exchange-Based Advanced Treatment or XBAT, and combines two mature drinking water treatment technologies in one—suspended ion exchange (SIX) and lime softening. It’s a sustainable and efficient process that can address salinity and TOC treatment concerns for water, wastewater, and potable reuse treatment.You will also read about Carollo’s digital apps and shops that can help utilities better manage and harness system data and information, all in user-friendly web browser programs. And lastly, we highlight two case studies in LA for stormwater capture projects that provide multiple benefits like environmental restoration, flood mitigation, and reduced reliance on external water supplies. I hope you enjoy reading this issue and learning about some exciting projects we are involved in around the country. Please contact me or the primary authors with any questions or comments! IN THIS ISSUETurning Data Into Decisions—A Guide to Carollo’s Digital Solutions for Water and Wastewater UtilitiesIon Exchange-Based Advanced Treatment (XBAT)—A Game-Changing Approach for Salinity and TOC TreatmentCity of Los Angeles’ Multi-Benefit Stormwater Capture Projects—Improving Stormwater Quality and Increasing Water Supply246Digital Apps: Enhancing Operational EciencyDigital Apps are at the forefront of Carollo’s digital deliverables, providing our clients with access to data, information, and decision-making through rich, graphical interfaces easily accessed from standard web browsers. Applications ranging from ﬁeld data collection apps, dashboards, and digital master plans to custom GIS web applications, and business decision support systems are delivered through dedicated Digital Shops.ProjectSHOP – Digital Apps for Program ManagersEciently managing intricate projects requires a robust Project Management Information System (PMIS). Carollo PM, a proprietary PMIS solution built on the Microsoft platform, addresses this need by integrating seamlessly into existing IT systems, using SharePoint, Teams, and Power Platform tools. Beyond PMIS, our digital tools extend to tracking Capital Improvement Projects (CIP) through customizable dashboards, reﬂecting project costs, drivers, and priorities. This adaptive system allows end-users to eortlessly adjust input data, providing substantial beneﬁts for long CIP horizons, and ensuring accurate project scheduling and ﬁnancial projections.AssetSHOP – Digital Apps for Asset ManagersAs utilities actively plan and prioritize infrastructure spending, CarolloDIGITAL’s cloud-based asset management tools enable the COMMENTARY / CURRENTSTURNING DATA INTO DECISIONS Using Digital Apps and SolutionsA Guide to Carollo’s Digital Solutions for Water and Wastewater UtilitiesCONTENT EDITOR Nick Webber / 208-327-2619 / nwebber@carollo.comGRAPHIC DESIGNER Silvia Higuera-Backlund EDITORIALNICK WEBBER, PE (nwebber@carollo.com) CURRENTS / IN THIS ISSUEANDY BALDWIN (abaldwin@carollo.com) Aging infrastructure and growing demands are accelerating the need to replace facilities and assets. Utilities are actively planning and prioritizing infrastructure spending while accounting for deteriorating facilities, population growth, and environmental changes. Knowing the “where and when” is fundamental to building cost-eective capital improvement programs, which require the ability to forecast necessary upgrades to the sewer, water, and recycled infrastructure systems.As agencies are exposed to increasing amounts of data and information, there is a growing need to use digital technologies to harness this data when making informed decisions that support planning, engineering, and operational activities. In addition, rapidly expanding software options can be overwhelming for agencies to select the best product that meets their needs. At Carollo, we recognize the pressing need for utilities to better manage data and information, and our CarolloDIGITAL team combines expertise in the water industry with innovative technology to guide water utilities through the selection and implementation of Digital Apps and solutions. Interactive, real-time dashboards All our apps feature accessible, beautifully designed dashboards that encourage your team to visualize, track, share, and update your digital projects and plans as changes occur.Whether you’re at the initial stages of digital integration or seeking advanced intelligence solutions, our team of experts is ready to guide you through the digital transformation journey.Get Started with ANDY BALDWIN CAROLLO DIGITAL SERVICES LEAD, PLANSHOP abaldwin@carollo.comecient collection, organization, and management of asset condition data. Additionally, our team collaborates with clients to select and implement other asset management and work order management software systems such as NEXGEN, Infor®, and Cityworks®. ANN CASEY ASSETSHOP acasey@carollo.comResilient O&M relies on multiple software systems to capture an accurate picture of system performance and deliver recommendations for timely response.DataSHOP – Digital Apps for Data ManagersDigital data and information are collected and processed using multiple software and hardware systems including sensor and measurement devices, databases and cloud-based systems, analytical and modeling software, dashboards, GIS, visual displays, and network and wireless communication technologies. Navigating this complex landscape requires a streamlined approach. Our Digital Water Roadmap guides utilities in deﬁning their needs, selecting software solutions, and conﬁguring their systems. Data and software systems integration is paramount. Our digital solutions are built on a deep understanding of water-related engineering data sources and formats, including meter data, SCADA protocols, modeling data, and more. When linked, these deliver concise information to engineering and operational teams.DAN BAKER PROJECTSHOP dbaker@carollo.comSHAWN DENT DATASHOP sdent@carollo.comANALYTICS (apps, models, algorithms) VISUALIZATIONS (Dashboards & Reports)COLLECTION (Automated & Manual Data Entry)Microsoft SQL AzureDATAWonderware SCADA HistorianInfor EAM, CMMSMicrosoft ExcelMicrosoft SQL ServerArcGIS Field Apps, FormsArcGIS (Enterprise Geodatabase)ArcGIS (Web maps, Dashboards)Power BIDream ReportAGOLFastﬁeld Relational & Media Data (Forms, Field, Inspections & Data Entry)STREAMINGTRANSACTIONALOpenFlows WaterSightOpenFlows WaterGemsOpenFlows SewerGems3PlanSHOP – Digital Apps for Planners Traditional master plans, which have used desktop-based technologies for decades, are evolving into digital master plans with information and results delivered through web browser and cloud-based platforms. Through Carollo’s infrastructure and water resource planning teams, we deliver digital master planning software applications to promote collaboration and to track and update master plans. This enables clients to evaluate demand projections, ﬁnd hydraulic deﬁciencies, validate model calibrations, and review proposed CIP projects and their associated cost projections.

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IX-HCO3-IX-R-HCO3-+NaOH + CO2Ca2+, Mg2+CaCO₃ (s), Mg(OH)2 (s)Ca(OH)2HCO3-DOC, SO42-, NO3-, Br-, Cl-, PO43-, etc.Lime SofteningSuspended Ion ExchangeBicarbonate RegenerationThe schematic diagram below illustrates the overall XBAT chemistry and the removal mechanism for dissolved anionic and cationic solutes.CURRENTS / FEATURE STORYRaw WaterReturn of Regenerated ResinResin Storage VesselResin Regeneration VesselSemi-plug Flow ContactorLamella Plate SettlerRegenerantWaste RegenerantRinse Water WasteRinse WaterWater FlowResin FlowResidual StreamChemical AdditionSIX Eﬄuent45Unlike conventional ion exchange in a ﬁxed-bed conﬁguration, SIX is a steady-state ion exchange process that keeps the resin ﬂuidized in a reactor.SIX PROCESS FLOW DIAGRAMION EXCHANGE-BASED ADVANCED TREATMENTA Game-Changing Salinity and TOC Treatment Approach for Drinking Water, Wastewater, and Reuse ApplicationsROSA YU, PhD, PE (ryu@carollo.com) / MELANIE PICKETT, PhD, PE EVA STEINLE-DARLING, PhD, PE / VINCENT HART, PEXBAT marks a signiﬁcant shift in the water-wastewater paradigm, oering a sustainable and ecient solution for addressing salinity concerns and advancing the future of responsible water management.A distinctive feature of SIX is its high resin regeneration frequency, which regenerates the spent resin after every single pass through the reactor. This keeps the resin’s ion exchange capacity only slightly utilized, allowing the resin to be regenerated by a weaker regenerant, such as bicarbonate, and at a much lower strength (3 percent) compared to a saturated sodium chloride solution typically used for resin regeneration. Resin regeneration using bicarbonate as the counter ion adds alkalinity to the SIX euent, making the treated water more suitable for lime softening and maximizes salinity reduction through calcium carbonate precipitation. Bicarbonate regeneration is the heart of XBAT, which synergizes the SIX and lime softening processes. Compared to RO, SIX produces a regeneration waste stream that is only 0.8% of the total feed water ﬂow. With XBAT, the bicarbonate nature of the waste regenerant also makes this residual stream more treatable and manageable than a concentrated chloride-based brine waste. For instance, bicarbonate, sulfate, phosphate, ﬂuoride, arsenic, silica, and TOC in the waste brine stream could be further removed via softening reactions with magnesium hydroxide and calcium carbonate precipitation. It could also potentially serve as a beneﬁcial amendment for alkalinity addition in biological nutrient removal processes in wastewater treatment applications, saving the costs associated with the addition of external chemicals. Water and wastewater professionals face a persistent challenge in managing salinity, a critical aspect of water quality that is often characterized through the measurement of total dissolved solids (TDS). Salinity is due to a complex mix of dissolved anions and cations, including chloride (Cl-), sulfate (SO42-), bicarbonate (HCO3-, or alkalinity), sodium (Na+), potassium (K+), calcium (Ca2+), and magnesium (Mg2+). In addition, dissolved organic matter (DOM), or total organic carbon (TOC), is an important constituent that must be managed in many water treatment applications to prevent the formation of disinfection byproducts or reduce oxygen demand in receiving waters. Conventional water treatment methods don’t address salinity because most physicochemical and biological treatment processes don’t remove inert ions such as chloride, sulfate, and sodium. In fact, some chemical treatment processes (e.g., coagulation) add anions to the treated water. Combined with the copious use of salts in household, commercial, and industrial enterprises, this can elevate salinity in the community-wide water cycle. Salinity removal is currently achieved through the use of reverse osmosis (RO), a highly eective, pressure-driven membrane process that removes almost all dissolved solutes, including salts. However, RO is not without challenges due to its concentrate waste stream that must be handled. This waste stream poses an issue, particularly for inland communities where ocean discharge is inaccessible or when deep well injection is not permittable, as well as for any communities where 8-15% water loss in the form of a brine waste stream is unacceptable.Enter Ion eXchange-Based Advanced Treatment (XBAT), a groundbreaking alternative method to reduce salinity. XBAT consists of a combination of two mature drinking water treatment processes: (1) suspended ion exchange (SIX) for the removal of negatively charged constituents (i.e., TOC, chloride, sulfate, bromide, nitrate, phosphate, etc.). Ion exchange resin regeneration, using bicarbonate as the counter ion, is key to the success of this approach and sets the stage for the second process (2) lime softening for cation removal (i.e., calcium and magnesium) as well as excess bicarbonate removal through calcium carbonate (CaCO₃) precipitation. Bench-scale testing of XBAT with secondary and tertiary wastewater euents has demonstrated a remarkable TOC removal rate of 50%, regardless of euent type and initial TOC concentrations. High removal rates were also observed for sulfate (99%), nitrate (90%), bromide (94%), and chloride (74%). Subsequent lime softening resulted in 92% calcium removal, 96% magnesium removal, and an overall 50% net TDS reduction. These results are promising indicators of XBAT’s potential to reduce or prevent salinity upcycling in potable reuse systems. Carollo is currently scaling up our evaluations of XBAT with an advanced wastewater treatment pilot at the City of Tampa, Florida, and a direct potable reuse treatment feasibility evaluation at Aurora Water, Colorado, with a pilot to follow soon. XBAT is poised to reshape the industry by unlocking the potential of potable reuse in inland communities, including areas in Colorado, Arizona, Utah, Texas, and beyond, where moderate salinity would otherwise pose challenges in selecting an advanced treatment approach that does not include RO.

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76Porous PavementBioswale around the Perimeter of the LakeExisting Weir StructureAutomated to Control Lake Level (Typ)E. 4th StreetE. 1St StreetS. St. Louis StreetRunoff Concentration PointsUsed for AnalysisPump toSewer or LakeGreen St. Elementson Boyle St.Hydrodynamic SeparatorStorage and RecirculationTreatment in Lake55Begin Additional Sidewalk along S. St. Louis St.Terraced Bioswalesto Treat Offsite FlowsEnd Additional Sidewalk along S. St. Louis St.1.5 AF multi-benefitsubsurface stormwaterquality unitLake Dredging and LiningConstructed WetlandsPotential Areas forDrywells and Green Street ElementsE. 4th StreetE. 1St StreetS. St. Louis StreetChemicalFeedLakeRecirculationSystemExistingPumpNewPumpIn-Lake Treatment and Recirculation SystemRecirculationCounty Storm DrainCity Storm DrainSewerCaltrans Storm DrainPerimeter BioswalesConstructed WetlandsRunoﬀ concentration pointsused for drywell analysisPotential areas to incorporatedrywells and green streetelements. Exact drywelllocations to be determinedat design phase.LEGENDOver the past several years, the City of LA’s Bureau of Sanitation and Environment (LASAN) has developed innovative projects that address LA’s growing stormwater quality challenges and dwindling drinking water supply, while also supporting and investing in communities that especially need it most. These projects have varying goals for water and environmental management. However, signiﬁcant ﬁnancial support and funding are required to complete them, which can be a challenge to secure. Over the course of four funding rounds, LASAN has secured $186.9M from the prestigious LA Regional Safe Clean Water (SCW) Program’s Regional Infrastructure Program, including: $25.2M for the Hollenbeck Park Lake Rehabilitation Project and $5M for the Sylmar Channel Project. The Regional Infrastructure Program requires all proposed eorts to describe how they intend to plan, build, and maintain multi-beneﬁt watershed-based projects to improve water quality, increase supply, and enhance communities. More speciﬁcally, the program ultimately scores projects according to the following criteria to determine eligibility for SCW funding: Ò Water Quality Benefits: This criterion is scored through an evaluation of water quality needs; municipal separate storm sewer systems (MS4) permit compliance; 24-hour storm capacity, event-based design details; and long-term performance. Ò Water Supply Benefits: This criterion is scored through an evaluation of water supply needs; stormwater or urban runo captured, inﬁltrated, or diverted to a separate groundwater recharge facility, a water treatment plant, or a sanitary sewer for conversion into recycled water; and the cost-eectiveness of the generated beneﬁts. Ò Community Investment Benefits: This criterion is scored through an evaluation of community investment and local support needs of a watershed area and the actual investment and support of local, community-based organizations gained through a project’s outreach and engagement. to comply with the MS4 Permit’s Enhanced Watershed Management Program (EWMP) Plans, meeting best management practice (BMP) performance goals and compliance targets for metals and bacteria. Additionally, these projects promote water conservation, ﬂood risk management, aesthetic improvements, recreational opportunities, and public education. The pollutant reductions for Hollenbeck and Sylmar were simulated using LA County’s Water Management Modeling System 2 (WMMS2), which comprises two primary continuous simulation models: Loading Simulation Program in C++ (LSPC) and System for Urban Stormwater Treatment and Analysis Integration (SUSTAIN). LSPC simulates rainfall/runo and pollutant build-up/wash-o. These simulated ﬂows and pollutant loads are then routed through SUSTAIN to simulate BMP performance. LSPC is parametrized by spatially deﬁning arrays of land uses, soil parameters, and slopes. WMMS2 utilized 96 combinations of land characteristics to simulate inﬂow to the projects. Spatially variable pollutant loads can be attributed to land use variability within the drainage area. The land use parameters have been calibrated for the LA region and have undergone peer review and regulatory input. The 85th percentile, 24-hour storms were simulated in SUSTAIN using LA County’s four-day banding time series. Load reduction conditions were simulated over a 10-year period to estimate the average annual performance. The annual water supply beneﬁt or inﬁltration volume was modeled using long-term continuous simulation with SUSTAIN. The inﬁltration volume was modeled using rainfall data over a 20-year period.Design of each project’s inﬁltration volume is optimized to capture as much of the 85th percentile, 24-hour storm or to achieve 80-percent pollutant reduction, whichever proves to be most cost ecient. Although the goal is to capture all of the project’s design storm runo, a cost-eective approach can allow a project to signiﬁcantly decrease localized ﬂooding and still meet—or even exceed—necessary compliance goals.Hollenbeck Park ImprovementsHollenbeck plans to implement diversions from inﬂuent storm drains, diverting ﬂows to a subsurface storage unit that allows for storage and inﬁltration, as well as pumping ﬂows to the lake. Lake enhancements consist of in-lake treatment, constructed wetlands, and perimeter bioswales. Along with the implementation of nearby drywells and green street elements, the project is expected to capture 347.7 acre-feet of runo annually, removing pollutants through treatment, including an 81-percent reduction of the primary pollutant zinc and a 100-percent reduction of trash from captured runo. ACHIEVING SUCCESS for LA’s Water Supply and Communities in NeedBy leveraging the funding opportunities provided by LA County’s SCW Program, LASAN is able to address many critical water needs across the City. Through this Regional Infrastructure Program, LASAN has improved water quality, reduced reliance on external sources of water supply, and provided localized ﬂood risk mitigation, environmental restoration, expanded recreational opportunities, and other impactful beneﬁts. These improvements are fulﬁlling the City’s sustainability and equity goals, as well as LA’s Green New Deal and One Water LA plans. LASAN will continue to implement these projects for at least the next ﬁve years, contributing to the SCW Program’s current estimated 56,915 acre-feet per year of average annual stormwater capture. Ò Nature-based Solutions: This criterion is scored through an evaluation of project elements that leverage nature-based solutions such as use of natural processes, use of natural materials, and removal of impermeable areas. Ò Leveraged Funds and Community Support: This criterion is scored through an evaluation of the percentage of funding matched and a demonstration of strong local, community-based support.Throughout Los Angeles’ (LA, City) history, imported water has been a necessity, making up a signiﬁcant portion of the City’s water sources. LA’s current infrastructure is unable to fully utilize the occasional storm events for beneﬁcial use or for much needed groundwater replenishment. With the City’s Green New Deal aiming to source 70% of its water supply locally by 2035, city leadership has placed an emphasis on multi-beneﬁt stormwater capture projects. These projects will aim to improve water quality, replenish LA’s groundwater basins, alleviate localized ﬂooding, and increase recreational beneﬁts.SUNSHINE SAUCEDO (ssaucedo@carollo.com) / CAROLINE BURGER, PE (cburger@carollo.com)Figure 1 - Existing Project Locations: Hollenbeck Park (left) and Sylmar Channel (right)Through these stormwater diversions, capture, and treatment BMPs, along with park and lake enhancements, the project will improve water quality and increase water supply within the much needed Upper LA River watershed.Sylmar Channel ImprovementsSylmar’s scope includes improvements to the channel for inline bioretention and additional green street network components, such as drywells and bioswales. Similar to Hollenbeck, this project also demonstrates signiﬁcant beneﬁts in improved water quality, with an over 80-percent reduction of zinc and a 100-percent reduction in trash from captured runo. Additionally, this project expects an annual capture of 206 acre-feet of water for aquifer recharge, enhancing LA’s water supply. By implementing various improvements and BMPs, ﬂood mitigation and environmental restoration are also promoted, ensuring improved public safety and increased recreational opportunities for the neighborhood. Figure 2 - Hollenbeck Park Lake Rehabilitation Project Proposed Concept Layout. LASAN’s Hollenbeck Park and Sylmar Channel ProjectsLASAN’s Hollenbeck Park Lake Rehabilitation Project (Hollenbeck) and Sylmar Channel Project (Sylmar) are both multi-beneﬁt stormwater projects that use nature-based solutions to improve water quality, increase water supply via groundwater recharge, and beneﬁt the local communities. Hollenbeck Park, within LA’s Boyle Heights neighborhood, is a 21-acre park with a 4.3-acre lake at the center. The lake receives several inﬂuent stormwater ﬂows from residential LA City and LA County storm drains, and from a nearby freeway storm drain. Sylmar Channel, an approximately 0.5-mile-long open channel, located in LA’s San Fernando Valley, transports ﬂow through the residential neighborhood to an LA County storm drain. Hollenbeck and Sylmar have been developed CASE STUDIESCity of Los Angeles’ Multi-Beneﬁt Stormwater Capture ProjectsImproving Stormwater Quality and Increasing Water SupplyCURRENTS / PROJECT UPDATE

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Currents 2024: Volume 1: XBAT-A Game Changer for Water Treatment

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