Best Management Practices (BMPs) in stormwater treatment are a suite of treatment alternatives to deal with pollutant removal problems from stormwater runoff. Biosorption-activated media (BAM) are green sorption media consists of recycled materials have shown excellent nutrient removal as an effective BMP by enhancing physicochemical and microbiological processes. In this study, Iron-Filling Green Environmental Media (denoted as IFGEM-3) and Advanced Green Environmental Media 1 and 2 (denoted as AGEM-1 and AGEM-2) were produced and tested for their adsorption capacities as well as removal and recovery potential for phosphate, nitrate, and ammonia against natural soil (baseline) collected from a stormwater retention basin in Ocala, FL. A set of isotherm and column tests were conducted at room temperature with varying contact times. Two media with the best adsorption performances were further tested to determine their life expectancy. The green sorption media characteristics and adsorption behaviors were further analyzed and realized by using a few existing isotherm models. The collected data on physical properties such as hydraulic conductivity, porosity, surface area, and density help justifying the comparative results. The results showed that AGEM-2 has the highest average nitrate removal efficiency (76.55%) when compared to IFGEM-3 (39.0%) and AGEM-1 (33.67%). Furthermore, IFGEM-3, AGEM-1 and AGEM-2 achieved the highest phosphate removals after only 30 minutes of contact time. It is indicative that IFGEM-3, AGEM-1 and AGEM-2 media all produced ammonia and the rates of production consistently increase as contact time increases. However, AGEM-2 generated an average of 35.22% more ammonia than IFGEM-3 and AGEM-1 suggesting it can be further utilized as a soil amendment. Natural soil showed no nutrient removal, however. The maximum adsorption capacities (qmax) derived by the isothermal test at high influent concentrations of 2mg/L phosphate and 2mg/L nitrate were found to be less than the qmax obtained from the column tests for IFGEM-3 and AGEM-2 with respect to nitrate. IFGEM-3 and AGEM-2 were further tested with respect to nitrate for their maximum adsorption capacities and their life expectancies based on column tests. The results indicated that AGEM-2 has a longer life expectancy and a higher adsorption capacity than IFGEM-3, in terms of nitrate removal, which is consistent with isotherm results. It is recommended that AGEM-2 be selected for nutrient removal in future stormwater treatment based on its better adsorption performance and recovery potential.

Nitrogen and phosphorus are often the limiting nutrients for marine and freshwater systems respectively. Additionally, stormwater often contains elevated levels of pathogens which can pollute the receiving water body and impact reuse applications [1-4]. The reduction of limiting nutrients and pathogens is a common primary target for stormwater best management practices (BMPs) [5]. Traditional BMPs, such as retention/detention treatment ponds require large footprints and may not be practical in ultra-urban environments where above ground space is limited. Upflow filters utilizing biosorption activated media (BAM) that can be placed underground offer a small footprint alternative. Additionally, BAM upflow filters can be installed at the discharge point of traditional stormwater ponds to provide further treatment. This research simulated stormwater that had already been treated for solids removal; thus, most of the nutrients and solids in the influent were assumed to be as non-settable suspended solids or dissolved solids. Three different BAM mixtures in an upflow filter configuration were compared for the parameters of nitrogen, phosphorus, total coliform, E. coli, and heterotrophic plate count (HPC). Additionally, genetic testing was conducted using Polymerase Chain Reaction (PCR), in conjunction with a nitrogen mass balance, to determine if Anammox was a significant player in the nitrogen removal. The columns were run at both 22-minute and 220-minute Empty Bed Contact Times (EBCTs). All the BAM mixtures analyzed were shown to be capable at the removal of nitrogen, phosphorus, and total coliform during both the 22-minute and 220-minute EBCTs, with BAM #1 having the highest removal performance for all three parameters during both EBCTs. All BAM mixtures experienced an increase in HPC. Additionally, PCR analysis confirmed the presence of Anammox in the biofilm and via mass balance it was determined that the biological nitrogen removal was due to Anammox and endogenous denitrification with Anammox being a significant mechanism.

Nutrient-laden stormwater runoff causes environmental and ecological impacts on receiving water bodies. Biosorption Activated Media (BAM) composed of the sand, tire crumb, and clay have been implemented in stormwater best management practices due to its ability to efficiently remove nutrients from stormwater runoff, such as in roadside linear ditches, via unique chemophysical and microbiological processes. In this study, a set of fixed-bed columns were set up to simulate some external forces in roadside linear ditches and examine how these external forces affect the performance of BAM. In our experiment, scenario 1 simulates the impact that animals such as tortoises, moles and ants produce conduits on the top layer of BAM. Scenario 2 simulates the presence of animals on BAM, together with external compaction. Finally, scenario 3 simulates external compaction such as traffic compaction alone. Furthermore, two baseline conditions were included to sustain the impact assessment of these three scenarios, respectively. They are the long-term presence of carbon in stormwater as carbon can be transported by stormwater runoff from neighboring crop fields, and the long-term presence of copper ions in stormwater as copper depositions can also be found because of electrical wiring, roofing, stormwater ponds disinfection and automobile brake pads in transportation networks. This systematic assessment encompasses some intertwined field complexity in real world systems driven by different hydraulic conditions, microbial ecology, Dissolved Organic Nitrogen (DON) reshape/removal, and long-term addition of carbon and copper (alone) on the effectiveness of total nitrogen removal. The removal efficiencies are substantially linked to varying microbial processes including mineralization, ammonification, nitrification, denitrification, and even dissimilatory nitrate reduction to ammonium, each of which is controlled by different dominant microbial species. The identification of DON compounds at the molecular level was done via a Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-IR-MS) whereas the quantitation of microbial species was done by using quantitative Polymerase Chain Reaction (qPCR). The results from the interactions between microbial ecology and DON decomposition were compared to the external forces and baseline conditions to obtain a holistic understanding of the removals efficiencies of total nitrogen. With the aid of qPCR and FT-IR-MS, this study concluded that the long-term presence of carbon is beneficial for nutrient removal whereas the long-term copper addition inhibits nutrient removal.

Coastal vulnerability has been gaining recognition as a critical issue, especially with the increasing predictions of sea level rise. Susceptibility to extreme events, eutrophication, and shoreline modification has left many coastal regions in a degraded state. Shoreline protection has traditionally taken the form of seawalls and offshore breakwaters which can be detrimental to both the local ecosystems and adjoining shorelines. The objective of this thesis is to analyze the hydrodynamic and bathymetric variation that occurs within Mosquito Lagoon, Florida following living shoreline and oyster reef restorations. The shoreline sites were sampled using a Before-After-Control-Impact (BACI) design and data were analyzed to ascertain the hydrodynamic and bathymetric variations that occurred resulting from plantings of emergent vegetation and deployment of biogenic wave break structures. Turbulent statistics were calculated to determine the effects of nearshore emergent vegetation on the incoming currents and waves. The vegetative growth in conjunction with the wave break structure was shown to reduce the onshore velocities to 46% of those observed at the reference site. Surveys among restored and degraded shorelines and oyster reefs exhibit average crest heights 10-20 cm lower in the restored sites. Nearshore slopes at the hard armored TM Seawall site were over 161% steeper than the restored sites comprised of emergent vegetation and wave break structures implying that scour was present at the toe of the structure from potentially reflected wave energies and increased swash velocities. Quantifying the hydrodynamic and geomorphic processes at work within restored shorelines and reefs may aide managers in best practices both in selection of viable restoration sites and with proper implementation of restoration techniques.

Small-system water purveyors must overcome many challenges to provide an adequate and safe water supply to its consuming public. This dissertation reports on research related to the application of biologically activated carbon (BAC) media filters for the treatment of well water to remove disinfection by-product (DBP) precursor matter, measured as dissolved organic carbon (DOC), at two treatment plants serving a small community water system. Four research questions were investigated individually in discrete, yet interconnected studies at two water treatment facilities processing groundwater that contained hydrogen-sulfide (~1.2 mg/L) and dissolved organic carbon (~2.0 mg/L). The first study revealed that BAC filters operated at the pilot-scale removed 50% of DOC regardless of carbon type or loading rate. A second study showed that GAC media replacement frequency, when transitioned from adsorption mode to biological-mode, would extend media change-out from 4 times per year to once to once every 2.5 years of service, providing a total savings of $40,000 per facility per operational year. A third investigation used genetic sequencing and quantitative polymerase chain reaction (qPCR) techniques using universal primers to identify the microbial communities within GAC filters operating in biological mode. Both sulfur-reducing and sulfur-oxidizing bacteria were identified as the predominant groups colonizing the GAC contactors. Genotyping of the different carbon types showed similar community composition; however, differences in the phylogenetic diversity of the samples were evident. A fourth study demonstrated that tray aerators could be integrated into a BAC process to decrease total trihalomethane DBPs entering the water distribution system.

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The United States Environmental Protection Agency regulates the lead and copper content of a public water system's finished water at the consumer's tap, through the Safe Drinking Water Act's Lead and Copper Rule (LCR), promulgated in 1991. This rule was recently changed through the LCR Revisions (LCRR), that took effect in 2021. The more stringent requirements of the LCRR motivated the City of Sarasota, Florida (City), to work with the University of Central Florida (UCF) on a study of the municipality's finished water corrosivity. Initially, this evaluation investigated the City's existing finished water corrosivity using linear polarization resistance (LPR) measurements and gravimetric coupon analysis at the pilot-scale, during which four phosphate-based inhibitors were tested for corrosion control. Based on the initial screening results, the City challenged UCF to derive a cost-effective, bench-scale method that could mimic distribution system conditions and be used to assess treatment technology infrastructure changes on finished water corrosivity. A modified corrosion jar test was developed that compared metal release of a high and low total dissolved solids water. The modified bench-scale method that omitted the effects of zero headspace using a sealed environment was found to be an improvement over conventional jar testing techniques. The results of the bench-scale experiments demonstrated the effectiveness and reproducibility of the modified method, as confirmed through analyses of variance. The modified bench-scale method simulated distribution system metal release, using first-order kinetic models, with R2 values of up to 0.98, demonstrating its beneficial use as a cost-effective alternative to otherwise more complicated pipe loop studies.

The production of clean water is emphasized under the United Nations goals for sustainable development (SDGs), enlightening the acute need of developing new sustainable technologies in all disciplines. SDGs have urged all engineers in the 21st century to mitigate pollution of drinking water sources and prevent all receiving waterbodies from the impact of agriculture discharge, wastewater effluent, and stormwater runoff. Current water matrix constituents of concern include traditional pollutants (i.e., total nitrogen and total phosphate), natural organic matters (i.e., total organic carbon (TOC), tannic acid), heavy metals (i.e., copper, calcium), and harmful algae toxins (i.e., microcystin), as well as contaminants of emerging concern (i.e., Per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, endocrine disrupting chemicals, personal care products). This study presents the most recent development of a suite of in situ cost-effective, scalable, and fit-for-purpose specialty adsorbents to simultaneously remove PFAS, TOC, total nitrogen, total phosphate, and microcystin through synergistic effect of different specialty ingredients. It is also aimed to clarify physiochemical removal mechanisms for the removal of color (tannic acid), nutrients (phosphate and nitrate), contaminants of emerging concern (PFAS) and algal toxins (Microcystin LR). The originality of these specialty adsorbents with chemical, molecular, and even microbial insights falls within the sustainable nature of specialty ingredients and wide availability tailored for scalable applications in any landscape.