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Showing 1 to 15 of 15 for “"hypolimnetic oxygenation"”.
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Predicting Oxygen Transfer in Hypolimnetic Oxygenation Devices
… model to predict the performance of several hypolimnetic oxygenators. The model is used to predict the oxygen transfer rate in a hypolimnetic oxygenator based on the initial bubble size formed at the diffuser. The discrete-bubble model is based on fundamental principles, and therefore could …
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Hypolimnetic Oxygenation: Coupling Bubble-Plume and Reservoir Models
When properly designed, hypolimnetic aeration and oxygenation systems can replenish dissolved oxygen in water bodies while preserving stratification. A comprehensive literature review of design methods for the three primary devices was completed. Using fundamental principles, a discrete-bubble …
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Geochemical drivers of Mn removal in drinking water reservoirs under hypolimnetic oxygenation
This study addressed the geochemical drivers of Mn removal, including pH, alkalinity and the presence of mineral particles. We conducted laboratory experiments and field monitoring at two drinking water reservoirs in southwestern Virginia – Falling Creek Reservoir (FCR) and Carvins Cove Reservoir …
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Controlling Dissolved Oxygen, Iron and Manganese in Water-Supply Reservoirs using Hypolimnetic Oxygenation
Hypolimnetic oxygenation systems, such as linear bubble-plume diffusers, are used to improve raw water quality. Linear bubble-plume diffusers were installed in Spring Hollow Reservoir (SHR) and Carvins Cove Reservoir (CCR). Diffusers induce mixing that aids distribution of oxygen throughout the …
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Hypolimnetic Oxygenation Mitigates the Effects of Nutrient Loading on Water Quality in a Eutrophic Reservoir
… lakes and reservoirs by increasing both hypolimnetic hypoxia and runoff, which will increase nutrient concentrations and degrade water quality. Hypoxic conditions can trigger the release of metals and nutrients from the sediments, i.e., internal loading, while storms can increase external …
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The effects of hypolimnetic oxygenation on the chemical, physical, and biological properties of a shallow drinking water reservoir
Hypolimnetic anoxia can result in higher internal phosphorus (P) loads from the sediments to the water column, thereby increasing nutrient availability, making preventing anoxia a major goal for lake managers to improve water quality. Side-stream saturation (SSS), a type of hypolimnetic oxygenation …
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High-frequency sensor data capture short-term variability in Fe and Mn cycling due to hypolimnetic oxygenation and seasonal dynamics in a drinking water reservoir
… Reservoir, Vinton, VA, USA) equipped with a hypolimnetic oxygenation (HOx) system. We quantified hourly Fe and Mn concentrations during two distinct transitional periods: reservoir turnover (Fall 2020) and initiation of the HOx system (Summer 2021). Our sensor system was able to successfully …
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Two-Dimensional Lake and Reservoir Modeling: Natural and Plume-Induced Mixing Mechanisms
… boundary mixing or advectively-driven inflows. Hypolimnetic oxygenation using bubble-plumes also leads to enhanced mixing. Whether natural or plume-induced, increased mixing will alter the waterbody properties. Conversely, the density structure affects the behavior of plumes as well as inflowing …
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Predicting induced sediment oxygen flux in oxygenated lakes and reservoirs
Bubble plume oxygenation systems are commonly used to mitigate anoxia and its deleterious effects on water quality in thermally stratified lakes and reservoirs. Following installation, increases in sediment oxygen flux (JO2) are typically observed during oxygenation and are positively correlated …
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Hydrologic and environmental drivers of metals (Al, Ba, Cu, Sr) in two drinking water reservoirs in southwestern Virginia
… over four years. One of the reservoirs has a hypolimnetic oxygenation system; the other does not and serves as a control. Using datasets of metal concentrations and other water quality measurements in the water column, suspended sediment and reservoir inflow, in addition to hydrologic …
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Remediation Strategies for Mercury Contaminated Lakes and Reservoirs Within the State of California
… use when remediating mercury contaminated lakes. Hypolimnetic oxygenation (HOS) was found to be the least problematic remediation method and nitrate additions were found to be the most problematic. Remediation through dredging is only ideal for severely polluted sediments and can be cost …
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Occoquan Reservoir and Watershed: A Water Quality Assessment 1973–2019
… issues, including nitrate addition to hypolimnetic waters and installation of a hypolimnetic oxygenation system. The goal of this study is to assess how current management strategies implemented in the Occoquan Reservoir have affected the water quality from 1973 to 2019, with particular …
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Dynamic forcing of oxygen, iron, and manganese fluxes at the sediment-water interface in lakes and reservoirs
… issue of global drinking water supplies. Hypolimnetic oxygenation systems (HOₓ) are being increasingly used to improve water quality in stratified reservoirs by increasing dissolved oxygen (O₂) concentrations and subsequently suppressing the release of soluble species such as iron (Fe) and …
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The sources and cycles of iron and manganese in surface water supplies
… showed that increasing DO concentrations through hypolimnetic oxygenation was effective for preventing the accumulation of soluble Fe in the water column. Although Mn oxidation increased under well-oxygenated conditions, soluble Mn still accumulated in the hypolimnion. Results from a laboratory …