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Full-Text Articles in Engineering

Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley May 2024

Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley

Civil Engineering ETDs

Meteorological, hydrological, and biogeochemical processes naturally control stream ecosystems. These processes define the frequency and distribution of precipitation and the supply and demand of solutes and particles to support aquatic food chains through space and time. Studies have also found that stream ecosystems are also controlled by anthropogenic activities, which occur on a much shorter timescale. These anthropogenic activities affect stream ecosystems' structure and function from local to planetary changes to the environment. It is essential for scientists and engineers to understand the relationships between naturally occurring processes and those created by human activities for a better interpretation of stream …


Co2 Storage Capacity And Injectivity Of Stacked Carbonates Of The Pennsylvanian And Permian In Western Nebraska, Lateef Lawal Dec 2023

Co2 Storage Capacity And Injectivity Of Stacked Carbonates Of The Pennsylvanian And Permian In Western Nebraska, Lateef Lawal

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Geological carbon storage (GCS) is a critical aspect of carbon capture and storage (CCS) in which captured CO2 from power plants and industrial processes is injected and stored securely underground. Potential subsurface rock formations include saline aquifers, depleted oil and gas reservoirs, unmineable coal seams and volcanic rocks. GCS technology has been proven in the United States and many other parts of the world as a net-zero carbon emission strategy to mitigate the current climate crisis of our planet. Unlike other states such as Wyoming, GCS projects are still in the early phases in Nebraska. The goal of this …


Aicropcam: Deploying Classification, Segmentation, Detection, And Counting Deep-Learning Models For Crop Monitoring On The Edge, Nipuna Chamara, Geng (Frank) Bai, Yufeng Ge Dec 2023

Aicropcam: Deploying Classification, Segmentation, Detection, And Counting Deep-Learning Models For Crop Monitoring On The Edge, Nipuna Chamara, Geng (Frank) Bai, Yufeng Ge

Biological Systems Engineering: Papers and Publications

Precision Agriculture (PA) promises to meet the future demands for food, feed, fiber, and fuel while keeping their production sustainable and environmentally friendly. PA relies heavily on sensing technologies to inform site-specific decision supports for planting, irrigation, fertilization, spraying, and harvesting. Traditional point-based sensors enjoy small data sizes but are limited in their capacity to measure plant and canopy parameters. On the other hand, imaging sensors can be powerful in measuring a wide range of these parameters, especially when coupled with Artificial Intelligence. The challenge, however, is the lack of computing, electric power, and connectivity infrastructure in agricultural fields, preventing …


Information Management And Bim Standards And Supports Inventory, Ryan Dempsey, Barry Mcauley, David Burke Nov 2023

Information Management And Bim Standards And Supports Inventory, Ryan Dempsey, Barry Mcauley, David Burke

Tools

The Digital Standards pillar consists of industry experts who champion the benefits of common rules, guidelines, and workflows that facilitate the improvement of information flow and information management across asset life cycles. Digital standards provide a common language that can be translated to technical specifications enabling clients, designers, contractors, and facilities managers, irrespective of their preferred tools, to communicate efficiently and reduce cost, rework, and disputes. Working closely with the Digital Procurement and Digital Education and Training pillars, this pillar is developing and delivering Irish Information Management/BIM (Digital Construction) guidelines for the sector.

This report summarises existing digital construction standards, …


International Information Management And Bim Best Practice Report, Ted Mckenna, Davitt Lamon Nov 2023

International Information Management And Bim Best Practice Report, Ted Mckenna, Davitt Lamon

Reports

In order to inform the Digital Leadership and Cultural Change pillar of the Build Digital, a study of international best practice in digital adoption within the built environment sector globally was undertaken and is presented here-in. In order to identify key learnings for Ireland in the context of digital transformation, eight countries were included in this study, namely, Denmark, Finland, Netherlands, Germany, United Kingdom (UK), New Zealand, Australia and Singapore. These countries were selected for various reasons, including the level of digital maturity, the scale of the built environment sector and geographic spread. Key data for each country is included …


Digital Construction Annual Survey 2022 Report, Davitt Lamon, Ted Mckenna Nov 2023

Digital Construction Annual Survey 2022 Report, Davitt Lamon, Ted Mckenna

Reports

The Annual Survey 2022 was conducted to assess the state of digital transformation in the Irish construction and built environment sector. This report presents the analysis of survey data, with a focus on implications for the Build Digital project and Build Digital’s five pillars: Digital Leadership & Cultural Change, Digital Standards, Digital Education & Training, Digital Procurement, and Sustainability & Circular Economy. Key findings from the survey indicated that a significant number of organisations have started their digital transformation journey, with many identifying themselves as proactive and possessing a clear business-focused strategy. However, a considerable cohort of respondents are keen …


Sustainability And Circular Economy Horizon Scan And Needs Analysis, Sadaf Dalirazar, Mark Kelly, Derek Sinnott, James O'Donnell Nov 2023

Sustainability And Circular Economy Horizon Scan And Needs Analysis, Sadaf Dalirazar, Mark Kelly, Derek Sinnott, James O'Donnell

Reports

The construction industry plays a crucial role in addressing the climate crisis as it is the largest global consumer of raw materials and contributes significantly to global energy consumption and emissions. Considering the world’s continuous population growth and the imperative to address infrastructure and housing demands the construction sector needs to adopt further sustainable strategies in its activities to reduce the pressure on natural resources. In addition, the Architecture, Engineering, and Construction (AEC) sector is responsible for generating substantial amount of waste known as Construction and Demolition Waste (CDW), which is projected to increase due to the future construction developments. …


An Interrogation Of The Role Of Ngos In Improving The Maritime Education And Training (Met) System In Kenya, Kulthum Hussein Salim Oct 2023

An Interrogation Of The Role Of Ngos In Improving The Maritime Education And Training (Met) System In Kenya, Kulthum Hussein Salim

World Maritime University Dissertations

No abstract provided.


Onshore Power For The Docked Container Vessels In Apapa Port Through Blended Finance, Oladayo Matthew Atilola Oct 2023

Onshore Power For The Docked Container Vessels In Apapa Port Through Blended Finance, Oladayo Matthew Atilola

World Maritime University Dissertations

No abstract provided.


Potential Roles Of Vessel Traffic Services (Vts) In Maritime Decarbonization, Suleiman Mustapha Bunza Oct 2023

Potential Roles Of Vessel Traffic Services (Vts) In Maritime Decarbonization, Suleiman Mustapha Bunza

World Maritime University Dissertations

No abstract provided.


The Cr(Iii) Exchange Mechanism Of Macroporous Resins: The Effect Of Functionality And Chemical Matrix, And The Statistical Verification Of Ion Exchange Data, Khizar Hussain Shah, Noor S. Shah, Gul Afshan Khan, Sadaf Sarfraz, Jibran Iqbal, Aneeqa Batool, Ahmad Jwuiyad, Shabnam Shahida, Changseok Han, Monika Wawrzkiewicz Oct 2023

The Cr(Iii) Exchange Mechanism Of Macroporous Resins: The Effect Of Functionality And Chemical Matrix, And The Statistical Verification Of Ion Exchange Data, Khizar Hussain Shah, Noor S. Shah, Gul Afshan Khan, Sadaf Sarfraz, Jibran Iqbal, Aneeqa Batool, Ahmad Jwuiyad, Shabnam Shahida, Changseok Han, Monika Wawrzkiewicz

All Works

This study focuses on investigating and comparing the influence of the surface functional groups and chemical matrices of macroporous resin on the Cr(III) exchange mechanism. The results discussed herein indicate that sulfonic resin removed Cr(III) ions with faster kinetics than carboxylic resin. Equilibrium was established within 15 and 7 min for the carboxylic and sulfonic resins, respectively, with a 99.5% removal efficiency at 333 K. The Langmuir exchange capacity was observed to be higher for the sulfonic resin (1.5 mmol∙g−1) than the carboxylic resin (0.80 mmol∙g−1) at 333 K. The adsorption isotherms obtained for the carboxylic and sulfonic resins were …


Nationalconference On Construction, Sustainable Infrastructure And Valorization Of Waste-2023, Subhrajit Pradhan Prof (Dr), Chandan Kumar Sahoo Dr., Niyati Nayak Prof., Tanushree Dalai Prof Oct 2023

Nationalconference On Construction, Sustainable Infrastructure And Valorization Of Waste-2023, Subhrajit Pradhan Prof (Dr), Chandan Kumar Sahoo Dr., Niyati Nayak Prof., Tanushree Dalai Prof

Conference Proceedings - Full Volumes

Gandhi Institute of Excellent Technocrats, Ghangapatna, BBSR is organizing a conference, “National Conference on Construction, sustainable Infrastructure and Valorization of waste-2023” on 6th& 7thOctober 2023, at GIET, Ghangapatna, BBSR. The conference provides a platform for deliberations on developing solutions that mitigate the impact of infrastructure on ecology and environment. Research and case studies on challenges, underlying opportunities and innovative ideas for the development of sustainable infrastructure will be presented and discussed.


Unhsc Street Sweeping Credit Calculator, Unh Stormwater Center Oct 2023

Unhsc Street Sweeping Credit Calculator, Unh Stormwater Center

UNH Stormwater Center

No abstract provided.


Modeling Leaf-Level Transpiration: Exploring The Consequences Of Assumed Saturated Vapor Pressure In Leaves, Danlyn L. Brennan Sep 2023

Modeling Leaf-Level Transpiration: Exploring The Consequences Of Assumed Saturated Vapor Pressure In Leaves, Danlyn L. Brennan

Dissertations and Theses

Understanding the dynamics of water transport through leaf intercellular airspaces (IAS) and its impact on transpiration is crucial for accurate predictions of plant water use and ecosystem response to changing climates. This study investigates the implications of assuming undersaturation of water vapor in the IAS for transpiration predictions and explores potential modifications to standard modeling approaches.

A dynamic 1D soil-plant-atmosphere continuum using a stomatal optimization model (SPAC-SOT) framework was used to simulate the response of tree species, P. edulis, to prolonged drought and varying environmental conditions. Comparisons between two model assumptions (saturated vs. undersaturated IAS) reveal notable differences in …


Effect Of Land Use Type And Stormwater Control Measures On Non-Point Source Phosphorus Concentrations And Loads In A Cold Climate Urban Subwatershed, Dillon H. Vyn Sep 2023

Effect Of Land Use Type And Stormwater Control Measures On Non-Point Source Phosphorus Concentrations And Loads In A Cold Climate Urban Subwatershed, Dillon H. Vyn

Electronic Thesis and Dissertation Repository

Non-point source phosphorus (P) exports from urban areas including contributions from different urban land use types and seasonal variations are not well understood, especially for cold climates. Additionally, the effectiveness of different stormwater control measures (SCMs) in reducing P concentrations and loads are poorly quantified with assessments rarely considering total watershed P loads. To address these gaps, detailed field monitoring of total P (TP), soluble reactive P (SRP), total suspended solids (TSS), and water quantity was conducted over a 19-month period in a mixed urban watershed in London, ON. Monitoring sites were located at watershed outlets, at the outlets of …


Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego Sep 2023

Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Introduction. To reduce the stream of solid waste going to landfills, innovative means for beneficial use are essential. The diversity and volume of organic wastes pose singular problems and opportunities for recovery and circularity. Common processes for organics include conversion to biofuels and carbonization to biochar, typically done by torrefaction (dry pyrolysis). Research on biochar explores its potential as pollutant adsorbent, agricultural or polluted soil amendment, biofuel (directly or as feedstock), and for carbon sequestration (Ighalo et al., 2022; Cavali et al., 2023). Recently, other processes at lower temperatures such as hydrothermal carbonization (HTC) offer new possibilities (Seshadri et al., …


Colloidal Behavior Of Nanobubbles And Their Application In Enhancing Plant Growth: Mechanisms Of Nanobubble Interactions With Microbial And Soil Species, Shan Xue Aug 2023

Colloidal Behavior Of Nanobubbles And Their Application In Enhancing Plant Growth: Mechanisms Of Nanobubble Interactions With Microbial And Soil Species, Shan Xue

Dissertations

Climate change has resulted in increasing uncertainties of water resources and disturbance on agricultural activities. For example, the shortage of water resources, land erosion and pollution from runoff significantly affect agricultural sustainability. This dissertation research focuses on the fundamental studies of nanobubble (NB) water and explores the benefits for irrigation to enhance plant germination and growth. Unlike bulk bubbles, NBs exhibit prolonged stability in water and possess large surface areas that facilitate efficient mass transfer and potential tailored reactions (e.g., disinfection). However, the enhancement mechanisms for NBs on seed germination and plant growth remain elusive.

This research first evaluated the …


Monitoring Remediation Of Organic Contaminants Using Electrical Resistivity And Induced Polarization Techniques, Angelos Almpanis Aug 2023

Monitoring Remediation Of Organic Contaminants Using Electrical Resistivity And Induced Polarization Techniques, Angelos Almpanis

Electronic Thesis and Dissertation Repository

Effective characterization and monitoring of subsurface processes associated with the remediation of sites contaminated by dense non-aqueous phase liquids (DNAPLs) remains a substantial environmental challenge. Geophysical techniques such as direct current (DC) resistivity and induced polarization (IP) offer the potential to considerably enhance our understanding of such complex phenomena occurring in the subsurface. However, despite extensive research highlighting the benefits of employing IP – in the time domain (DCIP) and/or frequency domain (spectral IP, SIP) – for contaminant investigations, more research is needed to understand the role of IP for monitoring DNAPL remediation. The goal of this thesis was to …


Performance Comparison Of Low-Cost Sensors Across Six Cities Of Continental United States, Md Hasibul Hasan Aug 2023

Performance Comparison Of Low-Cost Sensors Across Six Cities Of Continental United States, Md Hasibul Hasan

Electronic Theses and Dissertations, 2020-

In the field of air quality measurement, low-cost sensors have been extensively used for capturing high-resolution spatial and temporal pollutant concentrations. However, data accuracy and the impact of environmental conditions particularly temperature and relative humidity, remain a significant issue. Careful sensor calibrations against reference instruments are necessary for ensuring data accuracy and validity. This study investigated the effectiveness of multiple calibration methodologies (linear calibration, 3rd order polynomial calibration, and Random Forest, RF) for low-cost air quality sensor calibration across six cities (Atlanta, Portland, Riverside, Sacramento, New York City, and Phoenix) in the United States. The data for this study is …


Influence Of Ultrasound Machine Settings On Quantitative Measures Derived From Spatial Frequency Analysis Of Muscle Tissue, Scott K. Crawford, Stephanie A. Kliethermes, Bryan C. Heiderscheit, Greg Bashford Aug 2023

Influence Of Ultrasound Machine Settings On Quantitative Measures Derived From Spatial Frequency Analysis Of Muscle Tissue, Scott K. Crawford, Stephanie A. Kliethermes, Bryan C. Heiderscheit, Greg Bashford

Biological Systems Engineering: Papers and Publications

Background Ultrasound is a powerful tool for diagnostic purposes and provides insight into both normal and pathologic tissue structure. Spatial frequency analysis (SFA) methods characterize musculoskeletal tissue organization from ultrasound images. Both sonographers in clinical imaging and researchers may alter a minimized range of ultrasound settings to optimize image quality, and it is important to know how these small adjustments of these settings affect SFA parameters. The purpose of this study was to investigate the effects of making small adjustments in a typical default ultrasound machine setting on extracted spatial frequency parameters (peak spatial frequency radius (PSFR), Mmax, Mmax%, and …


The Potential Of Iron Electrodes In Electrochemical Cells For The Stabilization Of Synthetic Urine, Skyler Voisin Aug 2023

The Potential Of Iron Electrodes In Electrochemical Cells For The Stabilization Of Synthetic Urine, Skyler Voisin

All Theses

Source separation and urine treatment present the opportunity to significantly reduce influent concentrations of nitrogen and phosphorus in wastewater treatment plants and to capture those minerals for reuse. This study aims to use electrochemical cells with a sacrificial iron electrode to produce hydrogen peroxide in situ for the stabilization of urea while dissolving ferrous iron ions to promote the precipitation of phosphate into compounds such as vivianite (Fe3 (PO4)2 ∙ 8 H2O), a precipitate with potential uses in agriculture and manufacturing. Synthetic urine samples were treated as anolyte, then were given time to form …


Impact Of Granular Activated Carbon On In-Situ Reductive Dechlorination Of Chlorinated Solvents, Reagan Gregory Aug 2023

Impact Of Granular Activated Carbon On In-Situ Reductive Dechlorination Of Chlorinated Solvents, Reagan Gregory

All Theses

Treatment of chlorinated solvent-contaminated aquifers with in-situ activated carbon offers a simple yet cost-effective treatment opportunity, yet the interactions between activated carbon and the chlorinated solvents and their daughter products are not well understood.

The objective of this research is to demonstrate the impacts of in situ activated carbon on complete reductive dechlorination of chlorinated solvents in contaminated aquifer material with mixed dehalogenating cultures. This research seeks to characterize the sorption of trichloroethene and its daughter products cis-dichloroethene, vinyl chloride, and ethene to granular activated carbon and how that sorption relates to the removal of trichloroethene from contaminated material in …


High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman Aug 2023

High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

All Dissertations

Atmospheric carbon dioxide (CO2) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO2 concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO2 concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …


Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin Aug 2023

Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin

Open Access Theses & Dissertations

A pilot scale coupled photovoltaic-thermal solar powered desalination system was evaluated at the Brackish Groundwater National Desalination Research Facility (BGNDRF). The pilot system consisted of a 3-kW photovoltaic-thermal (PVT) solar panel array and a 2.3 kW photovoltaic (PV) array coupled with a 4 gal/min single-stage 4 membrane reverse osmosis (RO) desalination system. A heat exchange system was in place to provide simultaneous cooling for the PVT system and heating to the RO system feed water. This system was evaluated with three objectives in mind. The first objective was to identify whether cooling of the PVT panels resulted in a significant …


How Active Rainwater Harvesting May Help Reduce Nuisance Flooding: Flood Analysis And Social Barriers To Adoption, Isabel Lopez Aug 2023

How Active Rainwater Harvesting May Help Reduce Nuisance Flooding: Flood Analysis And Social Barriers To Adoption, Isabel Lopez

Open Access Theses & Dissertations

As urbanization continues to expand, fewer pervious surfaces are available to help reduce stormwater runoff from rainfall. The impacts of urbanization are becoming evident through sunny day flooding - flooding that occurs in areas not designated by the Federal Emergency Management Agency (FEMA) as flood zones. Nevertheless, water accumulates in low-lying areas and compromises street intersections and other parts of neighborhoods. Some methods can help alleviate the impacts of unexpected heavy rains, such as passive and active rainwater harvesting. As a pilot study, in a selected area in the northeast of El Paso, the level of adoption (e.g., what percentage …


Biomass-Mediated Metastable Zinc(Ii) Oxide Nanoparticles And Its Nanocomposites For Sustainable Water Treatment, Kazi Afroza Sultana Aug 2023

Biomass-Mediated Metastable Zinc(Ii) Oxide Nanoparticles And Its Nanocomposites For Sustainable Water Treatment, Kazi Afroza Sultana

Open Access Theses & Dissertations

Water is undeniably the most crucial resource that allows all living entities to thrive and survive. Due to a continuously growing population and the expansion of industrial sectors, water pollution has emerged as a global issue. Consequently, people face challenges in obtaining the required quantity and quality of water for their daily activities such as drinking, cooking, hygiene, and agriculture. Hence, there is a compelling need to develop an effective and environmentally friendly approach to eliminate harmful pollutants in water, promoting the establishment of a sustainable society with widespread access to clean and safe water resources. Although there are a …


Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling, Kaleb Boland Aug 2023

Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling, Kaleb Boland

All Theses

This study was inspired by a tree’s reliance on its root system that enables it to withstand a natural disaster, such as an extreme hydroclimatic event or hurricane. This curiosity has led to an investigation into what makes this possible, developing a new and innovative foundation configuration for infrastructure systems, and a new possible construction material and method. This study provides results on a material that does not have conventional testing procedures or standards: a tree root. The trees studied are common to the upstate of South Carolina, which are Pine, Sweetgum, and White Oak. According to the results, on …


Prairie Protector: Student Development Of Systems Thinking Habits In The Context Of Agroecosystems, Erin Ingram, Jennifer Keshwani Aug 2023

Prairie Protector: Student Development Of Systems Thinking Habits In The Context Of Agroecosystems, Erin Ingram, Jennifer Keshwani

Biological Systems Engineering: Papers and Publications

Introduction: The Great Plains ecosystem offers an opportunity for young people to gain knowledge about intricate systems through practical learning. The spread of woody plants into grasslands, known as the “Green Glacier,” poses a risk to biodiversity and animal production. Although effective management strategies exist, some land managers are reluctant to use them. It is critical to cultivate a scientifically literate population that can think systematically and make informed decisions based on STEM principles to address such complex agroecosystem problems.

Methods: In this study, semi-structured focus group discussions with high school students were analyzed to determine whether Prairie …


A Hybrid Lateral Flow Sand Filter Wastewater Treatment System: An Evaluation On The Treatment And Disposal Capabilities Of A Modified Sand Filter, Harry Mccaskill Iv Aug 2023

A Hybrid Lateral Flow Sand Filter Wastewater Treatment System: An Evaluation On The Treatment And Disposal Capabilities Of A Modified Sand Filter, Harry Mccaskill Iv

Theses and Dissertations

Decentralized wastewater treatment exists primarily in suburban and rural areas where centralized treatment is not an option. Traditional on-site treatment systems usually include the use of a septic tank and a drain field. This orthodox method works well when implemented into environments that are accommodating for the infiltration of effluents, and thus allowing for soil treatment. Unfortunately, there are some circumstances that prevent traditional systems from working such as impermeable soil conditions. The Wastewater Treatment System analyzed in this thesis was created to overcome such inhospitable environments. More specifically, this system is catered towards the rural residences of The Alabama …


Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer Aug 2023

Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District (HRSD) is recharging purified wastewater into the Potomac Aquifer via the Sustainable Water Initiative for Tomorrow (SWIFT) project. Conventional SWIFT treatment applies coagulation, flocculation, sedimentation, ozonation, biofiltration, granular activated carbon (GAC) adsorption, and ultraviolet disinfection to secondary effluent to produce water that meets drinking water standards for managed aquifer recharge. HRSD is considering implementing direct filtration as an alternative to conventional treatment for two additional SWIFT facilities. Direct filtration presents an opportunity for significant cost savings by eliminating sedimentation, shortening flocculation detention time, and reducing coagulant usage. Without upstream removal of solids and organics, however, biofilters …