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Pervious Concrete: A Hydrologic Analysis For Stormwater Management CreditSpence, Joshua 01 January 2006 (has links)
Portland Cement pervious concrete's ability to permit water infiltration has encouraged its use as a stormwater management tool. However, the material has suffered historically poor support due to a number of factors, including failures due to poor mix design and improper construction techniques, concern about lesser structural strength, concern about poor long term performance due to clogging of surface pores and undefined credit for stormwater management. This study focuses on long term performances of pervious concrete parking lots and their stormwater management credit. Before stormwater management credit could be estimated, it was necessary to develop a testing device to gather information from existing pervious concrete parking lots currently in use. Eight parking lots were examined to determine the infiltration rates of the pervious concrete, as well as to verify the soil makeup beneath pavement. A total of 30 cores were extracted from pervious concrete parking lots and evaluated for infiltration rates. Three of the sites had a pervious concrete section that included a gravel reservoir. Infiltration rates were measured using the application of an embedded single-ring infiltrometer. In an attempt to provide an estimate of credit, a mass balance model was created to be used for simulation of the hydrologic and hydraulic function of pervious concrete sections. The purpose of the model is to predict runoff and recharge volumes for different rainfall conditions and hydraulic properties of the concrete and the soil. The field derived hydraulic data were used to simulate infiltration volumes and rainfall excess given a year of rainfall as used in a mass balance operated within a spreadsheet. The results can be used for assessing stormwater management credit.
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Root-enhanced Infiltration in Stormwater Bioretention Facilities in Portland, OregonHart, Ted David 03 March 2017 (has links)
I evaluated the effectiveness of plant roots to increase infiltration rates within stormwater bioretention facilities (SBFs), roadside planter compartments that filter stormwater. SBFs attenuate harmful effects of stormwater by reducing peak flow and retaining pollutants, with increased infiltration that improves both these functions. Researchers have shown that roots can increase infiltration within greenhouse, lab, field, and test SBF settings. However, no researchers have yet measured either the extent to which different root characteristics can increase infiltration or the variation in root characteristics and their effect on infiltration rates among plant assemblages within currently functioning SBFs.
To determine if root-enhanced infiltration was occurring within SBFs, I hypothesized
1) there is a relationship between root characteristics and infiltration during late spring, and
2) seasonal root growth increases infiltration rates. Within Portland, OR, I measured infiltration rate from January 2014 to February 2015 and root characteristics from January-February (J-F) and May-June (M-J) 2014 in ten SBFs with "Elk Blue" rush (Juncus patens) and 1 or 2 trees of less than 8.4 cm stem diameter. During M-J, four root characteristics showed a positive relationship with infiltration rate, and two root characteristics showed a strong positive relationship with infiltration rate within the topsoil. Also, a relationship was shown between the increase (J-F to M-J 2014) in three root characteristics and the increase in infiltration rate.
To determine if root morphology and infiltration rates differed among SBFs with two different dominant vegetation taxa (small and large root biomass), I hypothesized 3) Juncus patens and tree dominant assemblage (greater root biomass) exhibits greater infiltration compared to the Carex dominant assemblage, 4) the increase in infiltration rate and root characteristics from J-F to M-J is greater in the Juncus compared to the Carex assemblage, and 5) root surface area density (RSAD) within Juncus SBFs shows a positive relationship with infiltration rate in late spring. I measured infiltration rate from January 2014 to February 2015 and root characteristics from January-February (J-F) and May-June (M-J) 2014 among five large-root (Juncus and tree) and five small-root biomass (Carex sp) SBFs. Juncus SBFs showed greater values for three root characteristics during J-F and five root characteristics during M-J 2014 compared to Carex SBFs. Also, Juncus SBFs showed an increase from J-F to M-J 2014 for five root characteristics while Carex SBFs showed no root increase. Juncus SBFs showed a relationship with four root characteristics and Carex SBFs a showed relationship with one root characteristic and infiltration rate.
This work strongly suggests plant roots increase infiltration, and thus the primary functions of SBFs. Different root characteristics appear to increase infiltration rate at different depths. Data also show larger-root biomass plants increase infiltration rate to a greater degree than smaller-root biomass plants.
I recommend considering several site and facility characteristics when determining the potential for root-enhanced infiltration. When selecting plant species to enhance infiltration, I recommend using several criteria, determining root characteristic values at certain depths, considering installation approaches, and accounting for regional climate changes.
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Sustainable Provision of Water Services in the United StatesHayek, Carolyn January 2024 (has links)
Most of the US population is served by large-scale, centralized drinking water, wastewater, and storm water systems built in the late 19th and early 20th century. Multi-trillion dollar investments are needed over the next 20 years to restore failing infrastructure, expand service areas to accommodate growing populations, and meet rising service provision costs driven by environmental and regulatory factors. A formal plan that recognizes the socioeconomic complexity of water services provision in the US is needed to guide these investments. Rising residential water charges over the last 20 years have raised concerns about household affordability of basic water services. Meanwhile, anywhere from 9 to 45 million people (4-28% of the US population) are affected by health-based drinking water quality violations each year. New technologies and evolving social goals have the potential to reshape the sector as we know it. This dissertation is a first attempt at synthesizing the sub questions around which spending is most critical and how rates can be structured for more equitable outcomes.
Research on the determinants of historic charge growth has been hindered by a lack of long-term longitudinal data. Unlike energy and telecom utilities, less than 20% of all drinking water utilities (primarily the investor-owned utilities) are economically regulated by public utility commissions. Absent local requirements, municipal water systems whose operating revenues are insufficient to cover operating expenses can make up for budget shortfalls with net transfers from the city general fund. We combine 10 American Water Works Association (AWWA) rate surveys to construct an 18-year unbalanced panel of charges at 446 large utilities (i.e., population served ≥10,000), revealing elevated 2-year compound annual charge growth (CAGR) between 2008 and 2012.
We estimate heterogenous impacts of the Great Recession on CAGR with an event study design of 204 utilities, comparing those with 2007 operating ratios below 1.2 (PCR) to those with ratios of ≥ 1.2 (FCR). Despite having the same cumulative 18-year CAGR, 2009-2013 CAGR was 3.9, 5.2, 5.2, and 5.7 percentage points per year higher at PCR utilities for 500, 1,000, 1,500, and 3,000 cf/month, respectively. Our findings demonstrate that large utilities who were likely relying on the general fund at the start of the Great Recession had to sharply increase their charges in the short-term to make up for decreased availability of that funding source. This indicates more immediate affordability challenges at utilities with operating ratios below 1.2 in the event of a similar economic shock. Additional data is needed to evaluate generalizability of these results to smaller systems.
Willingness to pay (WTP) for improved drinking water quality is estimated based on the cost of household averting behaviors taken during violations. While buying bottled water is a well-documented reaction to these violations, demographic and socioeconomic differences in water intake, preferred water supply alternatives, and shopping behavior suggest heterogeneity in the timing and form (e.g. soda vs bottled water) of household responses. We quantify this heterogeneity with an event study design using monthly household purchases of soda, water, and juice from the Nielsen Homescan Consumer Panel Dataset from 2004 through 2017. We find that, while households spend an average 14.8% more on bottled water during a month with a nitrate violation, these responses are concentrated in non-hispanic (NHP) Black and NHP Other households below the poverty threshold. Bottled water spending is 91.8% higher than usual in violation months for the former group and 90.0% higher than normal in the month after a violation for the latter. A simultaneous 103% increase in juice spending results in a 30.6% increase in combined beverage spending for NHP Black households below the poverty line in a violation month.
Meanwhile, an 85.3% increase in soda spending at NHP Other households drives a 58.9% increase in combined beverage spending in months with a violation and a 134% increase in soda spending, along with increased bottled water purchases, results in a 106% increase in combined beverage spending the month after a violation. NHP Black households with an IPR between 1 and 2 spend 129% more on soda during a violation. Our results indicate that studies focused only on bottled water purchases have systematically undercounted the effects on Hispanic, NHP Black, and Other NHP American households below the poverty threshold in their measure of WTP for improved drinking water quality or for the true cost of violations. Additional analysis is needed to determine if the tap water substitutions made by Hispanic households and households below the poverty threshold are increasing their overall sugary beverage consumption, which can have negative long-term health effects that are also not being considered.
Finally, we explore the ongoing implementation of onsite and distributed water reuse systems (ODWRS) to better understand how sociotechnical transitions can be supported when they are deemed to be a socially optimal solution. ODWRS collect previously discarded water flows as alternative water sources (e.g. rainwater, stormwater, greywater, wastewater) from one or more buildings and treat that water close to the point of generation or point of use to a quality deemed safe for its intended end use. Widespread adoption of ODWRS requires both acceptance of new technologies (e.g., water treatment, engineering) and alterations to established social systems(e.g., norms, stakeholder engagement, regulations). This has often been discussed as a single transition for all types of systems at the same time. However, the types of ODWRS being implemented in different areas are not the same. We compile and analyze the first national dataset of system-level information on ODWRS to identify clusters of system types associated with specific drivers. We find evidence of multiple transitions based on the combination of original source contamination level and end use application contact level. Low-contamination, low-contact are almost in the final stage of sociotechnical transition for many locations. Many areas with water supply constraints have already begun the transition for high-contamination to low- or medium-contact systems. Wastewater ODWRS are being implemented in places with effluent disposal constraints and stormwater ODWRS are being implemented in areas with combined sewers or high flood risk, though usually only for low-contact end uses.
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Big boxes and stormwaterFite-Wassilak, Alexander H. 11 July 2008 (has links)
Big-box Urban Mixed-use Developments (BUMDs) are mixed-use developments with a consistent typology that incorporate big-box retailers in a central role. They are also becoming popular in the Atlanta region. While BUMDs serve an important
economic role, they also cause issues with stormwater. This study explores integrating a
on-site approach to stormwater management into the design of BUMDs. These new designs not only significantly lower the amount of stormwater run-off, but also have potential for better, more attractive, developments.
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Hospodaření s dešťovou vodou v rámci zelené infrastruktury měst. / Stormwater management in frame of green infrastructures of cities.Novotný, Michal January 2021 (has links)
The aim of the diploma thesis is to create an evaluation and recommendation of measures in the field of water management within green infrastructures of cities according to appropriate size. These measures apply to typical urban buildings managed by cities of this size. The first part of the diploma thesis deals with a research focused on the current state of stormwater management within the green infrastructure of cities. The legislative aspect is also outlined and measures and technologies for stormwater management are described. The practical part of the diploma thesis deals with a case study for the design of stormwater management within the green infrastructure of the city of Třešť. Stormwater management methods for various buildings owned by the city of Třešť are designed and economically assessed.
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Zdravotně technické instalace provozní a výrobní budovy / Plumbing Systems for Factory BuildingNesvadbová, Petra January 2012 (has links)
Administrative building with changing rooms and washrooms facilities for associated industrial production in the faktory building. Use rainwater for flushing. Solution separated sewers. Rainwater brought into the retention tank where it is collected for flushing, excess rain water seeps through theblocks generated drainage system in the basement. Investigation using water-efficient fixtures and equipment. Designed saving shower heads, batteries, toilet tanks and efficient operation of the urinals.
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Biogeochemical Cycling And Nutrient Control Strategies For Groundwater At Stormwater Infiltration BasinsO'Reilly, Andrew M 01 January 2012 (has links)
Elevated concentrations of nutrients, particularly nitrate, in groundwater and springs in Florida are a growing resource management concern. Stormwater infiltration basins, which are a common stormwater management practice in the well-drained karst terrain areas of Florida, are a potentially important source of nutrients to the groundwater system because stormwater exits the basin by only evaporation or infiltration. To better understand the biogeochemical processes integrating stormwater infiltration impacts on groundwater resources in a field-scale setting, a combination of hydrologic, soil chemistry, water chemistry, dissolved and soil gas, isotope, and microbiological data was collected from 2007 through 2010 at two stormwater infiltration basins receiving runoff from predominantly residential watersheds in north-central Florida. Substantially different biogeochemical processes affecting nitrogen fate and transport were observed beneath the two stormwater infiltration basins. Differences are related to soil textural properties that deeply link hydroclimatic conditions with soil moisture variations in a humid, subtropical climate. During 2008, shallow groundwater beneath the basin with predominantly clayey soils (median 41% silt+clay content) exhibited decreases in dissolved oxygen from 3.8 to 0.1 mg/L and decreases in nitrate-nitrogen from 2.7 mg/L to less than 0.016 mg/L, followed by manganese and iron reduction, sulfate reduction, and methanogenesis. In contrast, beneath the basin with predominantly sandy soils (median 2% silt+clay content), aerobic conditions persisted from 2007 through 2009 (dissolved oxygen of 5.0â€"7.8 mg/L), resulting in nitrate-nitrogen of 1.3â€"3.3 mg/L in shallow groundwater. Soil extractable nitrate-nitrogen was significantly lower and the copper-containing nitrite reductase gene density was significantly higher beneath the clayey basin. Differences in moisture retention capacity between fine- and coarse-textured soils resulted in median volumetric gas-phase contents of 0.04 beneath the clayey basin and 0.19 beneath the sandy basin, inhibiting surface/subsurface oxygen exchange beneath the clayey basin. Subsurface biogeochemical processes at the clayey stormwater infiltration basin were further analyzed to better understand the effects of the highly variable hydrologic conditions common in humid, subtropical climates. Cyclic variations in biogeochemical processes generally coincided with wet and dry hydroclimatic conditions. Oxidizing conditions in the subsurface persisted for about one month or less at the beginning of wet periods with dissolved oxygen and nitrate showing similar temporal patterns. Reducing conditions in the subsurface evolved during prolonged flooding of the basin. At about the same time oxygen and nitrate reduction concluded, manganese, iron, and sulfate reduction began, with the onset of methanogenesis one month later. Reducing conditions persisted up to six months, continuing into subsequent dry periods until the next major oxidizing infiltration event. Evidence of denitrification in shallow groundwater at the site is supported by median nitrate-nitrogen less than 0.016 mg/L, excess nitrogen gas up to 3 mg/L progressively enriched in delta-15N during prolonged basin flooding, and isotopically heavy delta-15N and delta-18O of nitrate (up to 25 and 15 per mil, respectively). Isotopic enrichment of newly infiltrated stormwater suggests denitrification was partially completed within two days. Soil and water chemistry data suggest a biogeochemically active zone exists in the upper 1.4 m of soil, where organic carbon was the likely electron donor supplied by organic matter in soil solids or dissolved in infiltrating stormwater. The cyclic nature of reducing conditions effectively controlled the nitrogen cycle, switching nitrogen fate beneath the basin from nitrate leaching to reduction in the shallow saturated zone. Soil beneath the sandy stormwater infiltration basin was amended using biosorption activated media (BAM) to study the effectiveness of this technology in reducing inputs of nitrogen and phosphorus to groundwater. The functionalized soil amendment BAM consists of a 1.0:1.9:4.1 mixture (by volume) of tire crumb (to increase sorption capacity), silt and clay (to increase soil moisture retention), and sand (to promote sufficient infiltration), which was applied to develop an innovative best management practice (BMP) utilizing nutrient reduction and flood control sub-basins. Construction and materials costs, excluding profit and permit fees, for the innovative BMP were about $US 65 per square meter of basin bottom. Comparison of nitrate/chloride ratios for the shallow groundwater indicate that prior to using BAM, nitrate concentrations were substantially influenced by nitrification or variations in nitrate input. In contrast, for the new basin utilizing BAM, nitrate/chloride ratios indicate minor nitrification and nitrate losses with the exception of one summer sample that indicated a 45% loss. Biogeochemical indicators (denitrifier activity derived from real-time polymerase chain reaction and variations in major ions, nutrients, dissolved and soil gases, and stable isotopes) suggest nitrate losses are primarily attributable to denitrification, whereas dissimilatory nitrate reduction to ammonium and plant uptake are minor processes. Denitrification was likely occurring intermittently in anoxic microsites in the unsaturated zone, which was enhanced by increased soil moisture within the BAM layer and resultant reductions in surface/subsurface oxygen exchange that produced conditions conducive to increased denitrifier activity. Concentrations of total dissolved phosphorus and orthophosphate were reduced by more than 70% in unsaturated zone soil water, with the largest decreases in the BAM layer where sorption was the most likely mechanism for removal. Post-BAM orthophosphate/chloride ratios for shallow groundwater indicate predominantly minor increases and decreases in orthophosphate with the exception of one summer sample that indicated a 50% loss. Differences in nutrient variations between the unsaturated zone and shallow groundwater may be the result of the intensity and duration of nutrient removal processes and mixing ratios with water that had undergone little biogeochemical transformation. In order to quantify potential processes leading to observed nitrogen losses beneath the innovative BMP, an integrated infiltration basinâ€"nitrogen reduction (IBNR) system dynamics model was developed. Based on two simulation periods, the IBNR model indicated denitrification accounted for a loss of about one-third of the total dissolved nitrogen mass inflow and was occurring predominantly in the BAM layer. The IBNR model results in combination with the field-based biogeochemical assessment demonstrated that the innovative BMP using the functionalized soil amendment BAM is a promising passive, economical, stormwater nutrient-treatment technology. Further field- and laboratory-scale research on the long-term sustainability of nutrient losses and further elucidation of causative physicochemical and biogeochemical mechanisms would contribute to improved BAM performance and green infrastructure development in the future.
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Determining the efficiency of selected vegetated biofilters in reducing nutrients from urban stormwater in the city of Ekurhuleni, South AfricaBvumbi, Mulalo Justice 11 1900 (has links)
M. Tech. (Department of Civil Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / Over time, the quality standard of stormwater in the City of Ekurhuleni (CoE) has deteriorated due to industrial, commercial, residential and farming activities. Stormwater quality directly impacts the treatment chain of potable water, and therefore, it should be kept in check at all stages. Innovations in the biofiltration process can provide useful, practical solutions to overcome crucial stormwater pollution problems. In 2013, the CoE developed stormwater design guidelines and standards to be implemented for the design of stormwater management, which include the principles of Water Sensitive Urban Design (WSUD) and Sustainable Urban Drainage Systems (SuDS) in particular. The CoE stormwater design guidelines and standards do not provide details on how the city plans to implement SuDS treatment trains to reduce stormwater pollution experienced by the city. This study aimed to verify the efficiency and effectiveness of vegetated biofilters on the stormwater treatment using CoE – Olifantsfontain's natural stormwater and to determine the most suitable vegetation to be used in the region. The CoE experimental case study was conducted to assess the efficiency of selected vegetated biofilters in lowering the concentration of orthophosphate (PO4-3), ammonium (NH4+), and nitrate (NO3-) from Tembisa/Olifantsfontain stormwater.
In the experimental setup, six selected plant species were planted into 30 vegetated biofilter columns, namely: Agapanthus praecox (Dryland plant), Carpobrotus edulis (Dryland plant), Stenotaphrum secundatum (Dryland plant), Zantedeschia aethiopica (Wetland plant), Typha capensis (Wetland plant) and Phragmites australis (Wetland plant). The six species were grouped according to general habitats, i.e. three wetland and three dryland plants. Wetland plants were planted into fifteen vegetated biofilters, and dryland plants were also planted on another fifteen vegetated biofilters. The biofilters contained layers of sandy loam soil, coarse and and gravel sand. Each biofilter had a designated inlet and outlet section fitted with a gate valve to control retention time. The raw stormwater consisting of natural nutrient pollutants was applied to each vegetated biofilter through the inlet section. The samples were collected from the inlet and outlet of the six grouped vegetated biofilters during the month of June. All six plant species reduced outflow concentrations of PO4-3 and NH4+ by an average of 99% and 98%, respectively. The results also show that all plant species excluding Phragmites australis were able to reduce NO3- with outflow concentrations being reduced by an average of 58%.
From the results obtained, it may be concluded that all the six plant species may be suitable variants to be applied as biofilter material for the purposes of treating urban stormwater in the CoE. The reason is that the determined removal efficiencies for bio-retention fall within 50% – 60% for PO4-3, and 40% - 50% for NH4+ and NO3- respectively. The results also show that if the plant species were applied for SuDs in the CoE, there could be a great improvement in the urban stormwater quality with the consequent improvement in both surface and groundwater quality of the receiving water bodies in the area. Regardless of the nutrient removal by selected plant species, the inclusion of vegetation in a field setting would slow flow rates and thus encourage infiltration into the soil, improve water quality, and support urban biodiversity. In the CoE, all the selected species could be used in the SuDS treatment trains targeting PO4-3, NH4+ and/or NO3-. The case study results provide a informed records for the CoE in the future/intended application SuDs in the upgrade/rehabilitation of its stormwater system.
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Evidence Supporting Treatment Practice Based Delineation of Stormwater Runoff ZonesGorski, Jacob J. 01 October 2013 (has links)
Particles mobilized by stormwater negatively affect receiving surface waters. Stormwater best management practices (BMPs) can reduce solids along with associated pollutants in runoff but engineers and environmental managers have been long vexed by the problem of choosing the optimal BMP for a given situation. A common BMP process for solids removal is sedimentation. This thesis addresses the question of whether the effectiveness (and thus choice) of a sedimentation device can be estimated (and thus optimized) from the particle size properties of runoff, which, in turn, could be associated with specific runoff zones or land uses. Presented here is a series of experiments to determine the solids-removal capabilities of a manufactured oil-water separator that also removes solids via sedimentation. A statistical model developed from the experimental data shows that, under normal operating conditions, influent particle size can be used to accurately estimate effluent total suspended solids (TSS) for BMPs of this type. Relationships between particle size and particle-bound metal concentrations for Cu, Zn and Pb were then obtained from the literature and incorporated into the model to allow estimates of metal removal efficiencies based on TSS and PSD. The model can be used with an arbitrary particle size distribution (PSD); this allows effluent quality predictions to be made considering that particle sizes entering stormwater BMPs could vary due to anthropogenic, hydraulic or hydrologic factors. To place these experimental and modeling results in the context of an urban environment, samples of deposited stormwater solids were collected from residential areas, commercial areas and an industrial zone in Portland, Oregon, and the PSD of each sample was determined using light obstruction particle sizing. PSDs ranging over sizes from 3μm to 200μm vary among these locations. Areas with high anthropogenic impact were found to have PSDs skewed toward the smallest particle sizes. The statistical model developed here was then used to show that the effluent quality of the BMP tested would differ depending on the locations where solids were collected. The evidence presented in this thesis thus indicates that device performance will correlate with geographic locations or land use zone and validates further investigation into delineating the City of Portland's characteristic runoff zones and using the runoff characteristics of each zone to map it to the most desirable treatment practices.
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Hospodaření s dešťovými vodami v komerčních objektech / Stormwater management in commercial centersBekmukhambetova, Nuriia Unknown Date (has links)
This diploma thesis is devoted to a rainwater management in commercial and administrative buildings. The goal of this work is to describe rainwater management system with a focus on its later usage. The work is divided into theoretical and practical parts. The first part examines the binding conditions, as well as the individual technologies and devices that must be included in the implementation of a rainwater management system. The practical part of the work is an analysis of the possibility of using rainwater for the needs of the fire brigade in Havlíčkův Brod. The result of this work is a calculation of the approximate payback period of the proposed system.
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