The study analyzed hydro-climatic and land use sensitivities of stormwater runoff and quality in the complex coastal urban watershed of Miami River Basin, Florida by developing a Storm Water Management Model (EPA SWMM 5). Regression-based empirical models were also developed to explain stream water quality in relation to internal (land uses and hydrology) and external (upstream contribution, seawater) sources and drivers in six highly urbanized canal basins of Southeast Florida. Stormwater runoff and quality were most sensitive to rainfall, imperviousness, and conversion of open lands/parks to residential, commercial and industrial areas. In-stream dissolved oxygen and total phosphorus in the watersheds were dictated by internal stressors while external stressors were dominant for total nitrogen and specific conductance. The research findings and tools will be useful for proactive monitoring and management of storm runoff and urban stream water quality under the changing climate and environment in South Florida and around the world.

The Oak Ridge National Laboratory, Tennessee, was the site for a number of US Government projects during the 1940s and 1950s including the development of thermonuclear weapons. Chemical processes conducted at the site as part of these projects resulted in contamination of certain building areas at the ORNL. The purpose of this study is to develop a hydraulic-hydrologic computer model via XPSWMM to determine surface water flow rates and water stages within the drainage system during rainfall events and introduce a conservative contaminant into the system to trace peak concentrations of contaminants. The model was calibrated by simulating actual rainfall events over the area of interest. The model results were compared to that of Outfall 211’s monitored data. Trial 1 was most successful, where the cumulative flow rates produced by the model and the monitored data varied only by 0.5 cfs. A sensitivity analysis was completed by varying Manning’s coefficient and infiltration parameters within the area of interest. The sensitivity analysis concluded that the model was responsive to the variations presented; however, only minor differences were determined for the selected range of parameters, indicating robustness of model predictions. A hypothetical conservative contaminant was entered into the system as constant and varied timeseries. The resulting pollutographs produced by XPSWMM aid in the assessment for potential mobilization of contaminants and provide insight to where peak concentrations and loads occur under present conditions. Probability exceedance and probability distribution methods were used to analyze the timeseries of flow and pollutant concentrations collected during this study. Probability exceedance curves determined the percentage of time flooding occurred within the system under various conditions. The flow rates and concentrations produced by the transport analysis were best described by the Generalized Extreme Value, while the loading rates were best described by Log-logistic distribution.

No description available.

Continuing development of the Virginia Tech campus is increasing downstream flooding and water quality problems. To address these problems, the University has proposed the construction of a stormwater management facility to control the quantity and quality of stormwater releases to Strouble Creek, a tributary of the New River. The overall goal of this project is to design a stormwater management facility proposed for the Virginia-Maryland College of Veterinary Medicine at Virginia Tech in Blacksburg, Virginia that will reduce present and anticipated downstream flooding and water quality problems. Specific objectives of the project are: * control of flooding in lower areas by reducing the peak discharge while disturbing existing wetlands as little as possible, * address removal of major NPS pollutants such as total phosphorus (TP), total nitrogen (TN), metals, organic compounds related to petroleum and gasoline, and suspended sediment (SS) from stormwater runoff, and * design of a dam system that is able to withstand all driving forces and constructed in accordance with governing regulations. The design requirement to limit wetland disturbance below one acre was maintained. The requirement set by officials of Virginia Tech is based on the Nationwide Permit 26 of the Wetland Regulations. An individual permit process is thus avoided. Considering this demand, however, the freedom of the stormwater management facility design was significantly restricted. Resulting from the previous restrictions mentioned, the facility will include two ponds in series - a lower, dry pond and an upper, wet pond. The stormwater management system is designed to reduce the peak discharge. The dry pond is designed to detain water only for a short period of time, as opposed to the wet pond which is designed to retain water, thereby maintaining a permanent pool of water, and to change the characteristics of runoff. The wet pond was chosen to be of an Extended Detention wetland type. Aspects such as the availability of suitable area and detention volume governed the decision to make use of this type of stormwater wetland. The constraint on a maximum possible water surface elevation due to the Veterinary School1s road embankment, which crest elevation is at 2023 ft, was considered in the design. The stormwater management facility was designed to meet water quantity control requirements and to address water quality benefits. Storm water management regulations intending to mitigate the adverse effects of land development to streams and waterways were met. Requirements to limit peak discharges from 2-year and 10-year events to existing discharge levels were achieved. Several outlet structures for each of the ponds were investigated. The structures proposed are a perforated riser/broad-crested weir for the wet pond and a proportional weir for the dry pond. They were chosen as a result of analyses on hydraulic performance, maximum water surface elevations, drawdown times, peak discharge rates, and pollutant removal capabilities. The average pollutant removal capability of 75% of TSS, 45% TP, and 25% TN for an extended stormwater wetland, as found in the literature, is expected to be lower for the proposed facility, since the wetland-to-watershed-area ratio is considerably smaller (0.22%) than the required minimum ratio of 1%. However, other suggested desirable parameter for extended detention wetland systems such as required treatment volume, effective flow path length, and dry weather water balance will be maintained. The structural design of the dams was based on experience and research data. The dams are designed to consist of two zones, shell and core. The core extends as a cutoff trench 4 feet below the ground surface. Additionally, toe drain trenches and anti-seep collars along the pipe where penetrating the dam will be placed to collect and reduce seepage, respectively. Special considerations toward seepage problems were taken into account for both dams by placing a cutoff trench and a toe drain trench. Note: The appendix of this project report contains four AutoCAD files, that can only be viewed using AutoCAD. / Master of Engineering

No description available.

This thesis focuses on areas prone to inland floods and more specifically on the municipality of Acharnes, Attica, Greece. Usually, flood risk management strategies are treated as an engineering problem. Here, the floodplains/wetlands are going to be addressed as an asset and reveal the role of the landscape as a dynamic way for climate change mitigation and adaptation. Furthermore, such an approach can also offer potentials not only for water quality and management but also for benefiting the public spaces and open a discussion concerning awareness and engagement. Within the context of Attica, flood prone areas are not only ecologically deprived but also places of inequalities and loose social capacities. Acharnes is not an exception. Thus, the vision of this thesis is to investigate an alternative way for flood resistance by incorporating tools and methods capable of strengthening local communities. The thesis will investigate the following questions: •How can cities adapt to water issues and how can public space be used towards this end? •Can design for flood management be incorporated into a greater strategy connected to building relations?

As the global climate gets warmer, local extreme weather becomes more frequent, and it becomes more and more difficult to accurately predict the occurrence of extreme rainfall. At the same time, the threat and destructiveness of stormwater weather to urban water systems and cities are also increasing due to the continuous advancement of urbanization, the continuous gathering of urban population and the increasingly obvious urban heat island effect.Since it was first proposed, resilience thinking has become a very important idea in urban planning and research. With the continuous development of resilience thinking, its concept and connotation are also constantly improved and developed. It has developed from a single state of resilience at the beginning to cover all aspects of social, economic and ecological issues.This research aims to find the resilience level of the urban water system of Rotterdam, and find some typical cases of Rotterdam’s experience for other cities to learn. Based on the resilience thinking, this study takes Rotterdam as an example to comprehensively evaluate the resilience of the urban water system under stormwater disaster and urban flood and waterlogging. The first part of this thesis first introduces the urban water system, resilience thinking and other concept which this thesis use. In the second part, this thesis mainly introduced the specific analytical method and analytical framework, namely ASPIRE model. The third part will combine the analysis model with the example of Rotterdam, and comprehensively analyze the stormwater adaptive resilience of the urban water system. In the fourth part of this thesis, three engineering examples of Rotterdam which worthy of promotion and learning are introduced and summarized in detail. The last part of this thesis is the discussion and conclusion. Through this study, it is found that the urban water system of Rotterdam has high stormwater adaptive resilience and Rotterdam has many successful experiences which can be learned by other cities.

ABSTRACT: Umeå has had its troubles with flooding over the years. This study aims to describe and analyze flooding and stormwater management in the municipality of Umeå in Sweden. How the municipality is handling the responsibility to minimize the risk of flooding in problem areas and how they are planning to prevent flooding with stormwater management methods in both old and new districts of the city. With information gathered from the municipality itself and from other reports and websites of worth, I have compared the results I’ve gotten partly from my own field visits in the areas that are being planned for changes and partly from other reports. With that said, this study is a descriptive study with a focus on comparisons.

Permeable Interlocking Concrete Pavements (PICP) have seen increased popularity in the principles of Water Sensitive Urban Design and Sustainable Drainage Systems in recent years. To address certain design queries that still existed in industry, a two-year experimental study was conducted. It entailed the construction of an Infiltration Table Apparatus and subjecting a representative volume of PICP to hydraulic testing within it. The study aimed at determining the controls of the flow of water into and through these pavements, the effect of variations in construction materials and incline on them, the validity of the hydraulic testing methods currently being applied to them in industry and lastly, to inform on their infiltration rates. A host of permeability data for PICP was gained and it was found that both the choice of materials and the incline on which PICP are constructed, can change their hydraulic properties drastically. In general, the selection of lower permeability materials in the surface portion of the layer works decreased the overall permeability of the pavement, while increases in inclines did the same. In addition, it was found that field investigation techniques require revision and further innovation before they can be effectively applied to PICP. / Dissertation (MSc)--University of Pretoria, 2019. / Bosun Brick (Pty) Ltd. / Geology / MSc / Unrestricted

The chemical characterization of sediments accumulated in catch basins and stormwater ponds provides important information for assessing risks associated with management of these residuals upon removal of accumulated deposits in stormwater systems. In this study, over a period of 15 months, more than 150 residual samples were collected from 77 catch basin units and 22 stormwater ponds from 16 municipalities throughout the state of Florida. Concentrations (mg/kg) of metals and metalloids (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc) and trace organics (volatile organics, semi-volatile organics, herbicides, and pesticides) in the sediments were measured. In addition, the synthetic precipitation leaching procedure (SPLP) was utilized to evaluate pollutant leachability risk for a subset of the samples collected. Measured pollutant concentrations were compared to corresponding risk-based guidelines in Florida (i.e., Florida soil cleanup target levels) to assess potential human health risks of beneficial use of these residuals through land application. Leached concentrations were compared to risk-based water quality guidelines (i.e., Florida groundwater cleanup target levels) to examine the potential for groundwater contamination. Although several metals (arsenic, barium, chromium, copper, nickel, lead, and zinc) were routinely detected in the catch basin and stormwater pond sediments, their concentrations were generally lower than the Florida's risk-based cleanup target levels for soils. A small number of organochlorine compounds (e.g., 4,4′-DDE, 4,4′-DDT) were detected, but only in a limited number of the samples (less than 10%); leaching of trace organic pollutants above the Florida risk-based groundwater thresholds was rare. The results suggest that when land-applied or beneficially used, these residuals are not expected to pose a significant threat to human health or the environment and the results of this research will provide stormwater managers and environmental management authorities with a useful resource to examine proper disposal and beneficial use of catch basin and stormwater pond sediments.