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1
Vonck, Kevin J. "Towards more sustainable urban surface drainage a comparative case study of impervious cover policies in Portland, Oregon, and Seattle, Washington /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 247 p, 2009. http://proquest.umi.com/pqdweb?did=1833647401&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Testo completo
2
Morrison, Gregory Mark. "Metal speciation in urban runoff". Thesis, Middlesex University, 1985. http://eprints.mdx.ac.uk/6559/.
Testo completoAbstract (sommario):
A literature review has identified free and weakly complexed dissolved as well as solid surface associated, metal species as those forms most likely to be bio available. To analyse bio available Zn, Cd, Pb and Cu fractions in urban runoff a speciation scheme was devised which provided a relatively rapid technique for separating the dissolved and suspended solid phases of storm water into appropriate fractions. A new method, termed Dialysis with Receiving Resins, which responds to bio available metal species by incorporating a specially developed cysteine resin, within a dialysis membrane, has been devised and tested, A small scale gullypot study allowed the identification of six major processes which affect metal mobilisation and transport. The relevance of these processes is discussed with reference to gullypot outflow loadings of the different metal fractions. Acid rain mobilisation was found to greatly increase the levels of bio available free and weakly complexed metal fractions. Mass balance studies showed that Zn, Cd and Cu have a residence time in the road surface/gullypot system of little more than one storm event whereas Pb tends to be more persistent due to its predominant association with the solid phase. The speciation scheme was also applied to the analysis of metal fractions in storm water outfall samples collected from urban catchments in Sweden and the U.K. Significant concentrations and loadings of metals were found for both catchments with, on average, bio available metal forms representing 68% of the Zn, 76% of the Cd, 66% of the Pb and 32% of the Cu. Individual metal species were found to load at different rates onto metal chemographs and can be explained in terms of controlling parameters, as well as the influence of mobilisation and transport processes. Cadmium and Cu concentrations in storm water were regularly found to exceed Water Quality Standards and also to accumulate to significant levels in the Dialysis with Receiving Resins method. These metals may therefore represent a direct threat to receiving water quality.
3
Shutes, Robert Brian Emmerson. "The biological impacts of urban runoff waters". Thesis, Middlesex University, 1995. http://eprints.mdx.ac.uk/10698/.
Testo completoAbstract (sommario):
Introduction: My work with the Middlesex University Urban Pollution Research Centre has been conducted in the following areas: 1 Biological Monitoring of Urban Waters (Publications 1, 3, 5, 6, 25) Conventional biological methods and hydrobiological indices used for assessing water quality have been tested in urban streams and rivers and their limitations exposed. The impact of river engineering and physical disturbance on the substrate during storm events has been shown to influence significantly the index scores in addition to pollution impacts. The recommendation to compare biological with physico-chemical assessment of water quality has also been adopted by the National Rivers Authority. A model to predict the community diversity index score for urban stream macro invertebrate biota from recorded physico-chemical parameters was satisfactory for fairly clean waters and for moderate levels of pollution but not for serious levels of pollution (1). Reference streams and ponds in Trent Country Park on the fringe of North London were used for comparison with studies of the biota of urban waters (3,5). A system of river classification using a hydrobiological score system was proposed to complement the existing National Water Council system which was essentially based on chemical criteria (6). A study of the use of indicator organisms to monitor the impact of localised discharges of urban surface runoff and storm sewer overflows was commissioned by the Water Research Centre, the results of which are reported in paper no. 14. A review of the use of macroinvertebrates and plants as bioindicators in urban aquatic systems is included in publication 25. 2 Aquatic Ecotoxicology (Publications 3, 4, 5, 6, 7, 9, 11, 12, 14, 21, 24, 26, 28, 32, 34) 2.1 Heavy Metals Innovative methods have been developed for assessing heavy metal bioaccumulation in selected macro invertebrate species in urban waters. Traditionally, toxicity tests have been conducted in controlled laboratory conditions which do not simulate the natural environment. The use of caged macro invertebrates secured to the substrate in rivers, enables a more realistic determination of bioaccumulation and mortality rates to be made. The impact of storm events and chronic exposure to contaminated water and sediment has been investigated. At a time when new ecotoxicological tests are being introduced to the UK and the EC, the research has considerable potential application as a test for heavy metal impacts and the determination of environmental standards in freshwater. (The research has been sponsored by the Water Research Centre). VI Tissue concentrations of lead, cadmium, copper and zinc in selected macroinvertebrates collected from semi-rural and urban streams and ponds are reported in papers 3, 4 and 5. The relationship between urbanisation and macro invertebrate tissue, sediment and water metal concentrations and their spatial trends along the Salmon's Brook in North London is discussed in publication 6 and compared with the results from the A veiro Lagoon and its feeding rivers in North Portugal in paper 7. Tissue metal bioaccumulation in popUlations of caged Gammarus pUlex, Asellus aquaticus and Lymnea peregra in relation to ambient sediment and water metal concentrations, metal species bioavailability and organism feeding behaviour are discussed in publication 9. A comparison of mortality and metal uptake in aquatic macroinvertebrate species in field studies and laboratory experiments and a recommendation to reduce the length and lethal limit of the traditional 96 hour LC50 test is made in papers 11, 21, 24 and 32. The impact of storm sewer overflows from a sewage treatment works on caged macro invertebrates exposed to the discharges and to the receiving waters immediately downstream is reported in publications 12, 14 and 24. Principal component analysis was used to determine combinations of caged Aselius aquaticus tissue, sediment and water metal concentrations, precipitation volumes and antecedent dry periods which explained much of the variation in organism mortality and weight (28, 34). 2.2 Hydrocarbons (Publications 15 - 20, 29) Caged macro invertebrate species have also been used to determine hydrocarbon bioaccumulation in an urban stream and the Welsh Harp reservoir, a site of special scientific interest. Sediment and water hydrocarbon concentrations and macro invertebrate community diversity have been monitored along the stream and in the reservoir to investigate the impact of an oil boom. The development of biological and chemical techniques in this unique study of an urban freshwater wetland has led to considerable interest and further publications are planned. (The research has been sponsored by English Nature, formerly the Nature Conservancy Council). Publications 15 and 16 describe a baseline study of the ecotoxicological impacts resulting from oil pollution on the Welsh Harp and one of its receiving streams. Sediment and water concentrations of alkanes and P AHs and the tissue concentrations and temporal and spatial trends in selected caged macro invertebrates and fish are reported in publications 17, 18 and 19. The bioaccumulation of hydrocarbons by macro invertebrate species in laboratory tests and the corresponding mortality rates and their comparison with the results of field studies and controlling factors are discussed in publication 20. The results of the study are summarised in paper 29. vii 3 Aquatic Macrophyte Pollution Control (Publications 10, 13, 22, 23, 27, 31, 33, 35) Heavy metal uptake by the reedmace Typha latifolia, an aquatic plant species, has been investigated in urban wetlands and in greenhouse based studies. The research has shown a high level of tolerance by Typha to heavy metals and its biofiltration ability and creation of a sediment metal sink. It has led to the introduction of Typha in pioneering designs of constructed wetlands for highway runoff treatment in the UK. (The research is ongoing and is receiving sponsorship from industry and PCFC). A comparison of the water pollution control performance of Typha latifolia in the UK and Eicchomia crassipes in China is discussed in publication 10. Further details of the study of metal uptake in Typha latifolia and its associated sediment in the Welsh Harp and two ornamental ponds and a comparison with the results of a greenhouse based metal dosing experiment are given in papers 13 and 27 and summarised in 23 and 31. An analysis of the metal and hydrocarbon uptake and biofiltration ability of different species of aquatic macrophyte in an experimental pond receiving runoff from a car park in Washington State, USA is described in report 33.
4
Valeo, C. "Variable source area modeling in urban areas". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/NQ42884.pdf.
Testo completo
5
Wang, Yu. "Microbiological characteristics in urban stormwater runoff and sediments". Thesis, Middlesex University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.568524.
Testo completo
6
Hyde, Michael L. "Urban runoff quality in the River Sowe catchment". Thesis, Coventry University, 2006. http://curve.coventry.ac.uk/open/items/9c34fa51-7611-4362-844d-30d87ba84205/1.
Testo completoAbstract (sommario):
There have been no previous studies carried out on the impact of urban runoff in the Coventry City centre area. The culverted nature of the River Sherbourne, and many of its tributaries, makes the investigation of intermittent pollution and rainfall events expensive and impractical, when using traditional spot sample methods. Storm events have been monitored over a period of over 60 months upstream and downstream of the City, using continuous water quality monitors and auto-spot sample methods. The receiving waters of the River Avon had previously suffered annual fish mortalities as a result of summer storm events causing oxygen depletion. Previous studies (Clifforde and Williams 1997) on the impact of Coventry Sewage Treatment Works effluent on the watercourse, have suggested a major component of the intermittent pollutant load arising from the City (upstream of the Sewage Treatment Works), which requires evaluation and remediation. This research identifies the contaminants found during a series of storm events impacting on the River Sherbourne culvert, and discusses the relationship between them and the increased flow measured. The methodology was divided into 3 Phases; Phase 1 examined all of the watercourses in the River Sowe catchment, and identified the culverted streams and drainage system giving an indication of the presence of pollutant sources. Continuous monitors were deployed within the four identified drainage systems to pinpoint intermittent and illegal contaminated discharges, and these discharges were subsequently redirected to the foul sewer or stopped. Phase 2 examined the quality of the River Sherbourne culvert upstream and downstream of the city centre, and demonstrated (using continuous monitors and automated sampling), that six combined sewer overflows discharging to the watercourse upstream of the culvert were opening unsatisfactorily. The dissolved oxygen levels were significantly reduced during rainfall events (with a loss of diurnal variation), and total ammonium levels exceeded current water quality standards. The results were used to instigate a remediation scheme to replace the overflows with additional foul sewage capacity, and a single high-level storm relief. Phase 3 examined the impact of urban runoff during rainfall events after the improvements made following Phases 1 and 2. The results suggest a marked improvement in the water quality, with little impact from organic pollutants. Dissolved oxygen concentrations remained high during many of the post-remedial rainfall events, and ammonia levels remained largely insignificant. The results indicated a fall in pH levels during the rainfall events and increases in all of the heavy metals analysed, though not beyond current water quality guidelines. The efficiency of using continuous monitoring in Coventry was assessed and likely sources of the contaminants in urban runoff were considered. The statistics of compliance with percentile standards do not allow for short-term pollution or storm events, which may kill all aquatic life whilst not breaching water quality standards. Using continuous monitors to identify intermittent and illegal discharges in underground drainage systems was an efficient and cost-effective method of reducing the impact of urban runoff in a failing watercourse. The methodology can be applied to other urban areas to identify unidentified illegal and intermittent point sources. Routine monthly monitoring of an urban watercourse may not identify the peaks and troughs associated with rainfall events that may breach toxicological guidelines, and will not identify intermittent and unknown pollutant sources; particularly when discharging outside of normal working hours. This research was a unique and comprehensive investigation into the nature and composition of urban runoff in the City of Coventry, and local data gathered will be invaluable in promoting further research, improving local knowledge of the urban environment in preparation for the Water Framework Directive (2000/60/EC), and in planning for environmental improvements in the future.
7
Olson, Pamela Renee. "Novel Remediation Schemes for Groundwater and Urban Runoff". Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1306849957.
Testo completo
8
Berry, Carmel Therese. "Control of urban runoff through the use of permeable pavements". Thesis, Coventry University, 1995. http://curve.coventry.ac.uk/open/items/642e2d81-99a8-11c3-b6de-d9b60603249a/1.
Testo completoAbstract (sommario):
In order to control stormwater runoff engineers and hydrologists have used various techniques to attempt to reduce or delay the volume of water which reaches the sewer system. Recently, international approaches have favoured the idea of "source control" or "on-site" retention. This technique stores water in areas close to the point at which precipitation lands. Permeable pavements and similar stormwater control devices have not been exploited in the United Kingdom. Their adoption has been hindered by a lack of knowledge of their hydrological performance. This research aims to produce information on the hydrological performance of a car park surface and to produce a model which can predict the hydrological response to varying rainfall inputs. The objective of this thesis is to examine the hydrological behaviour of a model car park surface under varying rainfall conditions. The study has involved the construction of full-scale permeable pavement model car park structures and a rainfall simulator for use in the laboratory. A monitoring procedure was developed in order to measure inputs and changes in drainage, storage and evaporation over short (less than 2 hours) and long (up to 3 months) time scales. A range of rainfall simulations were applied to the model car park surfaces which differed in intensity, duration and volume. Hydrological processes were monitored over an 18 month period. Results suggest that evaporation, discharge and retention in the structures were strongly influenced by the particle size of the bedding material and the surface blocks. In general an average of 55% of a 15 mm 11-1 rainfall event could be retained by an initially dry structure. Subsequent simulations suggest that approximately 30% of a 15 mm rainfall event could be stored by an initially wet structure (with a minimum time interval of 72 hours). Sediments were also applied to the car park structures in order to monitor the effects of clogging on hydrological performance and to quantify the ability of the structures to act as a primary screening site for sediments. The application of sediments to the structure showed that evaporation from the structure increased by as much as 25-30%. Laboratory simulation of clogging effects was also compared to data gathered from field sites and the results suggested that laboratory simulations provided a good approximation of the migration of sediments in the structure. A model of the hydrological performance of the structure has been developed to be used as a predictive tool. The model relates rainfall inputs to water retention and discharge output over consecutive rainfall events. It also allows evaporation and long-term retention by the structure to be estimated over differing lengths of dry periods. The model results indicate that discharge was predicted to an accuracy of 78% (based on a percentage difference between the observed and predicted values), and evaporation and retention were predicted to an accuracy of 80%.
9
Goyen, Allan. "Spatial and temporal effects on urban rainfall/runoff modeling". Online version, 2000. http://hdl.handle.net/2100/626.
Testo completoAbstract (sommario):
University of Technology, Sydney. Faculty of Engineering.Although extensive worldwide literature on urban stormwater runoff exists, very few publications describe runoff development in terms of its basic building blocks or processes and their individual and accumulative significance in response to varying inputs and boundary conditions. Process algorithms should respond accurately to varying input magnitudes and characteristics as well as to changes in antecedent conditions. The present state of estimation errors involved in many current numerical simulation techniques has been reviewed in this thesis. A significant amount of errors that are presently encountered for have been explained in terms of undefined process response not explicitly included within many modelling methodologies. Extensive field monitoring of intra-catchment rainfall and runoff within an urban catchment at Giralang in Canberra, which is typical of Australian urban catchments, was carried out over a 3-year period to define and measure individual runoff processes. This monitoring work led to a greater understanding of the processes driving the aggregation of local runoff from many sub-areas into the runoff observed at full catchment scale. The results from the monitoring process prompted a number of approaches to potentially reduce standard errors of estimate from model-attributable errors based on improvements to definable catchment response mechanisms. The research isolated a number of basic building blocks associated with typical residential allotments, that can be grouped into roof drainage, yard drainage and adjacent road drainage. A proposed modelling approach was developed that allowed these building blocks at an allotment scale to be simply computed using storage routing techniques. This then aggregated via the total catchment’s public drainage system isochronal characteristics utilising a “process tree” approach to provide full catchment scale runoff response. The potential reduction in estimation errors utilising the developed procedure was assessed using a large number of recorded events from the Giralang catchment monitoring data. The proposed numerical modelling approach was found to provide significant improvements over current methods and offered a scale-independent and stormindependent methodology to model catchments of any size without the need for changes to any of the runoff routing parameters. Additionally the approach permits the flexible sequencing and inclusion of a wide range of different urban drainage structures within a catchment that are representative of the local characteristics. The developed procedure also includes a spatially varied water balance approach to infiltration estimation that is more suited to future continuous simulation models. The developed “flexible process tree” approach provides an important step forward in the numerical modelling of complex urban drainage systems. This can reduce errors of estimate by improving intra-catchment process representation.
10
Stovold, Matthew R. "Modeling urban stormwater disposal systems for their future management and design /". Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0111.
Testo completo
11
Hsieh, Chi-hsu. "Engineering bioretention for treatment of urban storm water runoff". College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/239.
Testo completoAbstract (sommario):
Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Civil Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
12
Li, Tong. "Trace metals in urban stormwater runoff and their management". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31891.
Testo completoAbstract (sommario):
In the Greater Vancouver Regional District (GVRD), non-point source pollution from an urban
watershed and a diesel bus loop was assessed in terms of trace metal contamination in the stormwater
runoff.
In the Brunette River watershed study, Northwest Hydraulic Consultants (NHC) collected streambed
sediment and suspended sediment from selected streams during 7 storm events over 2003. From 1993 to
2003, the major stormwater contamination happened in the most industrialized Still Creek. The
streambed Cu, Mn, Fe, and Zn concentration increased by 1.5, 1.7, 1.9, and 1.1 times, respectively. And
the suspended Cu, Mn, and Zn increased by a factor of 2.1, 4.2, and 1.5, respectively. The streambed
sediment exceeded probable effect level in Still Creek and Stoney Creek to varying degrees with Cu and
Zn. The land use is considered to be the origins of these toxicants. Statistically, the magnitude of
suspended metal concentration in μg/l is negatively correlated with the drainage areas. While the —
concentrations in mg/kg, especially for metal Cu and Zn, showed strongly and positively correlation with
the traffic density. Positive correlation existed between the suspended metal loading (kg/yr) and the
imperviousness and the catchment area. No apparent trend was observed in terms of export coefficient
(g/ha/yr) and land use. 1062 tons of sediments were trapped by Burnaby Lake in 2003. This sediment
overloading problem causes serious metal contamination in the lake.
Stormwater runoff quality was monitored in 15 storm events from October 2004 to June 2005 in the
diesel bus loop in the University of British Columbia. The dissolved Cu and Zn Event Mean
Concentration (EMC) exceeded the EPA discharge criteria in 2 and 4 events each, which occurred in the
dry season. Diesel bus traffic contributes' a large portion of Cu, Fe, Zn contamination since the average
bus loop trace metal levels were much higher than the GVRD urban levels. The runoff trace metal
concentrations are strongly related to the antecedent dry period, and are weakly related to the traffic
density and the rainfall intensity. From the catch basin filter evaluation, high removal efficiencies on
suspended metal/solids were achieved with low particulate loading in the filter chamber. The filter
performed well for the dissolved metal removal before the non-reversible saturation was reached. Each
kilogram of filter media has an absorption capacity of 52 gram oil and grease, 20 milligram Mn, and 16
milligram Zn.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
13
Mantle, James Duncan Guy. "On-site reduction and attenuation of urban stormwater runoff". Thesis, Nottingham Trent University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358899.
Testo completo
14
Nyström, Fredrik. "Coagulation process characteristics and pollutant removal from urban runoff". Licentiate thesis, Luleå tekniska universitet, Arkitektur och vatten, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-73091.
Testo completoAbstract (sommario):
Many different stormwater control measures (SCMs) can be implemented in order to mitigate issues with polluted stormwater flows into receiving water bodies. The treatment function of SCMs is commonly based on the removal of particles by sedimentation, thereby also removing pollutants associated with particles. In recent years, more attention has been given to characterizing and understanding of different particle size fractions and their association with pollutants commonly found in stormwater. It has become increasingly clear that the smaller sized particles are very important pollutant transporters and should be considered when designing and implementing SCMs. However, the settling velocities for smaller sized particles are very low and may not be effectively removed in existing SCMs. One treatment process with a proven ability to enhance sedimentation is coagulation/flocculation, widespread in water and wastewater treatment, but with very few accounts of it being used in a stormwater context. This thesis aims to investigate the treatability of stormwater with a coagulation/flocculation process. This includes the determination of operating conditions, the dominating coagulation mechanism and the reduction efficiency of stormwater related pollutants. The objectives of the thesis were achieved in laboratory tests treating stormwater in a jar-testing procedure. An initial screening of primary coagulants and flocculant aids was conducted using an urban snowmelt mixture. Five of the chemicals were then selected for an extended testing regime which was setup up to determine the operating conditions where maximal turbidity reduction was attained by measuring the pH, conductivity, alkalinity and zeta-potential over the tested doses for each coagulant. Criteria used for chemical selection included high turbidity reduction, low dose requirement and low pH/alkalinity impacts. Charge reversal was observed at positive zeta-potential indicating that the dominating coagulation mechanism was charge neutralization. The content of turbidity/total suspended solids, total organic carbon, total metals and hydrocarbons by >90%. Dissolved copper was reduced by 40% on average, and the reduction rates for dissolved zinc were varying with up to a 300% increase, presumably due to changes in pH, leading to a higher mobility. Changes in the particle size distribution after coagulation/flocculation as compared to sedimentation indicated an effect on the size fraction corresponding to smaller particles. The performance of the coagulation/flocculation process was also tested on road runoff collected from a central road in Luleå with a high traffic intensity. Two coagulants were tested, iron chloride and pre-hydrolyzed aluminum chloride. Reduction rates for the total metal fraction were >90% on average for both coagulants, but for the dissolved metal fractions differences could be observed between the coagulants with the iron chloride resulting in higher reductions for dissolved chrome (57% compared to 34%) and copper (47% compared to 30%). Both products increased the dissolved fractions of nickel and zinc due to lower final pH.
15
Westerström, Göran. "Estimating urban snowmelt runoff by the temperature index approach". Licentiate thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 1986. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25793.
Testo completo
16
DeCook, K. J., e L. G. Wilson. "Ground-Water Recharge from Urban Runoff and Irrigation Returns". Water Resources Research Center. The University of Arizona, 2014. http://hdl.handle.net/10150/314278.
Testo completoAbstract (sommario):
No date on item.Preliminary information on urban runoff from selected small watersheds in the Tucson area indicates that average annual runoff from the urbanized areas is more than four times as much as that of a comparable undeveloped desert area, and may be ten times as much in some individual years. The urban runoff contains relatively high concentrations of bacterial loading and dissolved organics; although it is not now known to be a seriously hazardous source of pollutants in ground water, urban runoff should be monitored with increasing urban growth, especially for content of organics, microorganisms, and trace metals. Additional study also should be given to the travel-time regime of runoff from the small tributary urban watershed to the major stream channels where recharge mainly occurs. Deep percolation from irrigation return flows was evaluated during a one -year study for the U.S. Geological Survey's "Southwest Alluvial Basin, Regional Aquifer System Assessment Program". Objectives of the study included (1) identifying sources of recharge information, (2) collecting and summarizing available recharge information, (3) identifying methods for interbasin transference of recharge values, (4) characterizing deep percolation models, and (5) itemizing methods for overcoming data gaps. Apparently there is a difference in opinion among irrigation experts on the extent to which recharge from deep percolation occurs. One reason for the difference of opinion is that field measurements of the flux and velocity components of deep percolation through the vadose zone are scarce, particularly for deep alluvial basins. Similarly, there is a need for a simple, theoretically-based model of deep percolation /recharge. Many of the data deficiencies could be overcome by conducting lumped and site-specific field studies. Such studies, although expensive, would be timely in light of the current interest in ground-water management.
17
Kwong, Pui-ki. "An investigation of stormwater quality in Kai Tak Nullah". Click to view the E-thesis via HKU Scholors Hub, 2005. http://lookup.lib.hku.hk/lookup/bib/B40707386.
Testo completo
18
Maass, Amanda. "Analysis of Best Management Practices for Addressing Urban Stormwater Runoff". The University of Arizona, 2016. http://hdl.handle.net/10150/608331.
Testo completoAbstract (sommario):
Sustainable Built Environments Senior Capstone ProjectDuring Tucson rainstorms, many roads and neighborhoods experience high levels of flooding on the city’s street networks. This phenomenon creates unsafe road conditions, damage to the road infrastructure, and excessive urban stormwater runoff that is potentially polluted. The vast quantities of impervious surfaces in the urban landscape impede the rainwater’s ability to infiltrate the ground, thus resulting in increased volumes of runoff during a rainstorm. Stormwater management is used by municipalities and communities to address the previously mentioned adverse impacts of stormwater runoff. Various techniques and strategies used in stormwater management include, low impact development (LID), green infrastructure, and better site design (BSD) strategies implemented during design stages to reduce stormwater runoff levels. In addition, local governments can establish stormwater utilities and policies in order to help address and better manage the issue of stormwater runoff within urban areas. The primary research questions of this study will include: What are the most effective best management practices and techniques to address urban runoff? What combination of best management practices and government policies will be the more effective in addressing Tucson’s urban runoff problem? Accordingly, this study will examine a variety of policies and techniques to address stormwater runoff, and then, based on this information, provide a suggestion of the best practices and techniques that may be feasible for implementation in Tucson.
19
Wren, J. H. "Pathways utilized by heavy metal pollutants in urban stormwater runoff". Thesis, Aston University, 1986. http://publications.aston.ac.uk/14239/.
Testo completoAbstract (sommario):
The research concerned the assessment of the pathways utilized by heavy metal pollutants in urban stormwater runoff. A separately sewered urban residential catchment of approximately 107 hectares in Chelmsley Wood, north-east Birmingham was the subject of the field investigation. The catchment area, almost entirely residential, had no immediate industrial heavy metal input, however, industry was situated to the north of the catchment. The perimeter of the catchment was bounded by the M6 motorway on the northern and eastern sides and was believed to contribute to aerial deposition. Metal inputs to the ground surface were assumed to be confined to normal suburban activities, namely, aerial deposition, vehicular activity and anthropological activities. A programme of field work was undertaken over a 12 month period, from July 1983 to July 1984. Monthly deposition rates were monitored using a network of deposit cannisters and roadside sediment and soil samples were taken. Stormwater samples were obtained for 19 separate events. All samples were analysed for iron, lead, zinc, copper, chromium, nickel and cadmium content. Rainfall was recorded on site with additional meteorological data obtained from local Meteorological Offices. Use was made of a simple conceptual model designed for the catchment to substantiate hypotheses derived from site investigations and literature, to investigate the pathways utilized for the transportation of heavy metals throughout the catchment.
20
Boe, Jennifer Barber. "Removal of hydrocarbons from urban stormwater runoff by gravity separation". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10312009-020227/.
Testo completo
21
Loemker, Rabea. "Nutrient removal in a constructed wetland treating urban stormwater runoff". Thesis, Queensland University of Technology, 2002. https://eprints.qut.edu.au/36156/1/36156_Loemker_2002.pdf.
Testo completoAbstract (sommario):
Urban stormwater runoff is a major concern in Australia and in other parts of the world, because of its potential severe, quantity and quality related impacts on the
health of environmental water systems. Many stormwater quality improvement devices (SQ IDs) have been developed over time. Constructed wetlands are a relatively new SQID, and are the specific topic of this thesis. The construction of wetlands for stormwater quality improvement has been prompted by the effectiveness of natural wetlands in storing stormwater runoff
during rainfall events and improving water quality during flow through the system
during dry periods. However, like other ecosystems, wetlands are profoundly complex. Wetlands for stormwater quality improvement vary greatly in performance
due to differences in design, climate, catchment characteristics and other factors. In particular, nutrient removal efficiencies vary widely among wetland systems. This is a result of the lack of understanding of fundamental aspects of these extremely complex, heterogeneous systems, and of phenomena responsible for nutrient removal. In particular how these are affected by environmental conditions and
system design.
This thesis investigated the performance of a constructed wetland treating
stormwater runoff from an urban catchment. It aims to improve understanding of the performance of wetlands in removing nutrients from stormwater runoff, in a
subtropical climate. A three-year-old wetland system (Keith Boden wetland) located in an urban
catchment in Brisbane, Australia, was investigated over two distinct seasonal periods, autumn and summer. Water samples were collected at eight locations in
different parts of the wetland. Additionally, sediment samples were taken on the last sampling date of the autumn sampling period. Results from this study showed that this wetland system was most effective and
consistent in removing nitrate and orthophosphate during both seasons (autumn and summer). However, concentrations of both nitrate and orthophosphate were considerably lower within the wetland during summer. The removal of nitrate was mainly due to denitrification. The removal process for orthophosphate varied within the two sampling periods: Biological uptake of orthophosphate appeared to be high during the summer period. The processes of orthophosphate retention during the autumn sampling period were more difficult to understand and it was more likely that uptake of orthophosphate was overshadowed by the release of orthophosphate from the sediments. Other forms of nitrogen and phosphorus that were measured displayed variable behaviour within the wetland system. During summer vertical temperature and dissolved oxygen profiling showed stratification on some occasions.
A detailed discussion of the methodology and results of this study highlighted the complexity of wetland systems and showed that any study of these systems is
necessarily limited. Nonetheless, the experimental studies conducted as a part of this research have provided insights into the systems functioning and greater awareness of possible behaviours. This is important knowledge to aid the monitoring, design
and application of wetlands as SQIDs.
22
Li, Zeying, e 黎泽英. "Hydrologic performance of bioretention system and permeable pavement for potential applications in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/209498.
Testo completoAbstract (sommario):
Stormwater management is always a problem in Hong Kong since its development from a fishing village. Contributed by abundant precipitation, hilly topography, and dense urban development, flooding has been causing enormous economic losses to Hong Kong and is a main focus of local stormwater management. With the construction of many conventional hardcore engineering stormwater management structures in recent decades, such as underground detention tanks and stormwater tunnels, the flooding problem in Hong Kong has been well alleviated. It is now the time to move forward and incorporate more sustainable stormwater management principles and techniques, namely the strategy of low-impact development (LID), into the local practices in Hong Kong. Stormwater should be viewed not only as a problem, but also as a valuable resource.
This research aims at a feasibility study on the possible applications and hydrologic benefits of bioretention and permeable pavements under the local conditions of Hong Kong.
The buildability of infiltration devices in Hong Kong is examined by constructing pilot-scale physical models of both bioretention and permeable pavements in this study. Hydrologic monitoring of these physical models under Hong Kong rainfall events is carried out for at least one wet season. The monitoring data are analyzed to evaluate the hydrologic performance of bioretention and permeable pavements, as indicated by peak flow reduction and volume retention of stormwater runoff. The long-term hydrologic performance is also evaluated by the numerical model SWMM (Stormwater Management Model). After model calibration and validation using field data on the physical model, SWMM isused to simulate bioretention performance for the past ten year precipitation records of Hong Kong under systematic variations of two relevant parameters, namely the exfiltration rate and the area ratio of bioretention to catchment.
Results show that both bioretention and permeable pavements are feasible to be applied in Hong Kong. The hydrologic performance of bioretention is influenced by the precipitation patterns, the size of bioretention, the stormwater storage, and the properties of soil. As in common practice, the available storage of bioretention is much smaller than design rainfalls in Hong Kong. Therefore, peak flow reduction shall not be the target of incorporating bioretention in local storm drain designs. The influence on long-term water balance in the urban area may be considered as the main benefits from bioretention, using the annual retention ratio as a performance indicator. The hydrologic performance of permeable pavements is influenced by the storage depth provided by the gravel layer and the properties of in-situ soil. Considerably good peak flow reduction and volume retention are obtained in the experimental permeable pavements subjected to the local extreme precipitation events. In actually applications, the storage of permeable pavement may be designed to capture the total depth of design storms in Hong Kong, after which peak flow reduction may be obtained.
It is anticipated that this research can provide reference information on both the design and hydrologic benefit estimation of bioretention and permeable pavements practices for applications in Hong Kong.published_or_final_version
Civil Engineering
Master
Master of Philosophy
23
Lancaster, Cory Deyne. "A low impact development method for mitigating highway stormwater runoff, using natural roadside environments for metals retention and infiltration". Online access for everyone, 2005. http://www.dissertations.wsu.edu/Thesis/Summer2005/c%5Flancaster%5F072105.pdf.
Testo completo
24
Goodsell, Timothy Holman. "Trace Element Inputs from Natural and Anthropogenic Sources in an Agricultural Watershed, Middle Provo River, Utah". BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6223.
Testo completoAbstract (sommario):
Water chemistry in rivers is impacted by a variety of natural and anthropogenic processes including agricultural runoff, urban runoff, storm runoff, groundwater inputs, and the built environment. In this study we used trace element concentrations (including As, B, Ce, Co, Cu, Li, Mn, Rb, Sb, Sr, Tl, V, and Zn) and continuous measurements of flow rates and specific conductance to investigate dynamic processes affecting water quality in a rapidly urbanizing agricultural area typical of the western U.S. The middle Provo River, located in northern Utah, USA, was selected as the study area because it is well instrumented with water quality stations and streamflow gauges. We sampled 6 sites on the middle Provo River and 15 sites on tributaries in the watershed a minimum of 5 times between April 2014 and March 2015 to evaluate potential contributions from surface water and groundwater inputs to the Provo River. Additional water samples were collected at 13 cold, thermal, and mixed cold/thermal springs in Heber Valley during summer 2014 to evaluate regional groundwater chemistry. Samples were also collected during two storm events including high frequency sampling in a tributary and road-puddle samples to characterize potential storm runoff chemistry. Specific conductance data loggers were deployed in tributaries to monitor effects of precipitation and other runoff on the middle Provo River at 15-min intervals. See Table 1 for a summary of sampling events. Middle Provo River water chemistry is impacted by natural groundwater inputs as well as surface water tributaries. Li, B, Sr, As concentrations increased dramatically (3-10 fold) downstream of the confluence with a major tributary, Snake Creek. Snake Creek had average As concentrations of ~15 µg/L above the confluence with Provo River and accounted for roughly 20% of the flow to the middle Provo River, but increased the As concentration in Provo River ~4 fold. Thermal springs had ~20 and ~80 times higher concentrations of As and Li, respectively, relative to cold springs and was found to be a major contributor of trace elements to Snake Creek and the middle Provo River. Cl mixing calculations indicated that groundwater contributions increased downstream with up to 15% of the flow to the middle Provo River being contributed within the most downstream reach. Tributaries were found to impact the Provo River based on specific conductance fluxes in tributaries corresponding to fluxes in the river. Notably, Spring Creek, a dominantly agricultural tributary, accounts for >40% of the annual V load and >18% of the annual U, Mn, Pb, Ba, La, and Ce loads to the middle Provo River. The trace elements B, Li, As, and Sr which are found in high concentrations in groundwater, were strongly correlated with Provo River specific conductance and may indicate a potential method of predicting select trace element concentrations in the middle Provo River based on specific conductance data. Filtered puddle samples collected during a storm event had higher concentrations of Co, Cu, V, and Zn, but lower concentrations of major and select trace elements including As, Li, and Sr, relative to the middle Provo River. This study has implications for understanding water quality in complex coupled human-natural systems.
25
Memon, Fayyaz Ali. "Simulating the influence of roadside gully pots on runoff quality". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343723.
Testo completo
26
Camacho, Gema Liliana. "GIS-based tool for assessing hydraulic performance of drainage infrastructure system in El Paso". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Testo completo
27
Trejo-Gaytan, Julieta. "Treatment of urban runoff at Lake Tahoe : low intensity chemical dosing /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
Testo completo
28
Tota-Maharaj, Kiran. "Geothermal paving systems for urban runoff treatment and renewable energy efficiency". Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4909.
Testo completoAbstract (sommario):
Water and energy are two of the most precious and essential resources which are inseparably connected; vital for the survival and well-being of humanity. Sustainable water resources and energy management emphasizes the requirement for a holistic approach in meeting the needs of the present and future generations. In order to indentify the needs and obstacles relating to water reuse and renewable energy initiatives, Hanson Formpave in partnership with The University of Edinburgh implement a five-year pilot project between May 2005 and June 2010. The research project addressed the use of sustainable urban drainage systems (SUDS) such as permeable pavements systems (PPS) and integration of renewable energy tools such as geothermal heat pumps (GHPs). The research uses the novel and timely urban drainage system and focuses on water quality assessment when incorporated with GHPs. Twelve-tanked laboratory scaled experimental PPS were evaluated at The King’s Building campus (The University of Edinburgh, Scotland) using different compositions. Variations in designs included the presence of geotextiles layers and geothermal heating/cooling applications. The experimental rigs were examined for a two year period (March 2008 to April 2010). Two types of urban stormwater were used in the analysis; (i) gully pot liquor and (ii) gully pot liquor spiked with Canis lupus familiaris (dog) faeces. This urban wastewater represented the extreme worstcase scenario from a storm event, which can occur on a permeable pavement parking lot. The pavement systems operated in batch-flow to mimic weekly storm events and reduce pumping costs. Six PPS were located indoor in a controlled environment and six corresponding PPS were placed outdoors to allow for a direct comparison of controlled and uncontrolled environmental conditions. The outdoor rig simulated natural weather conditions whilst the indoor rig operated under controlled environmental conditions such as regulated temperature, humidity and light. The project assessed the performance of these pavement rigs with the integration of ground-source heating and cooling, standalone PPS and the abilities for water quality treatment from a physical, chemical and microbiological perspective. The performance efficiency of the GHP was measured by the energy efficiency ration (EER) for steady state cooling efficiency and the coefficient of performance (COP) for the heating cycle efficiency. Findings from the combined PPS and GHP system and standalone systems were able to significantly lower levels for all physiochemical and microbial water quality parameters in the range of (70-99.99%) respectively. Outflow concentrations for all pavement systems met the European Commission Environment Urban Wastewater Treatment Directive (91/271/EEC). The presence of geotextiles resulted in a significant reduction of contaminants when compared to PPS systems without (p <0.05). Photocatalytic disinfection with titanium dioxide (TIO2) was applied to the effluent from PPS for further treatment and polishing of the stormwater. After the photocatalytic disinfection, the water met the requirements for the United States Environmental Protection Agency (US EPA) water recycling guidelines and the World Health Organisation (WHO) guidelines for potable water consumption with regards to microbial contamination. An Energy and temperature balance was developed for two PPS using a 4th order Runge-Kutta numerical method to model the heat fluxes and energy balance within the pavement system. Machine learning techniques such as artificial neural networks (backpropagatioin feed forward neural networks) and self-organising maps (SOM) were applied and successfully predicted the effluent concentrations of nutrients, biochemical oxygen demand (BOD) and microbial pollutants. The overall outcome of this research is a significant contribution to the development of a new generable of sustainable and eco-friendly pavements. The research project proves scientifically that PPS is one of the most appropriate systems for GHP installation and does not affect its efficiency for water pollutant removal.
29
Hamade, Firas Nadim. "Sediment removal from urban runoff using seep berms and vegetative filtration". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50271.
Testo completoAbstract (sommario):
Previous field demonstration projects in metro-Atlanta have shown that seep berms, which are elongated sedimentation basins at the outlet of a disturbed land area, can provide high suspended sediment trap efficiencies with respect to coarse sediments on construction sites having drainage areas greater than five acres. Previous literature has shown that vegetative filter strips are efficient traps for fine suspended sediment in stormwater runoff. A combination of a seep berm and vegetative filter in series was studied in this thesis as an erosion control measure with quantification of its flow resistance and sediment removal efficiency. First, a field demonstration project was implemented to evaluate seep berms as a viable erosion control measure through a side-by-side comparison with the more commonly-used silt fences on construction sites with drainage areas less than five acres in metro Atlanta. High suspended sediment trap efficiencies were recorded for the seep berm on two separate sites, and the seep berm was shown to be superior to silt fences with respect to sediment control in the site runoff. Then a vegetative filter was studied in the laboratory in a specially-built flume for that purpose. The relationship between vegetative drag coefficient and various parameters reflecting flow conditions and vegetation density in steady, uniform open channel flow was studied in the flume. Both rigid, emergent vegetation and submerged, flexible vegetation were studied at two different plant densities. The application of porous media flow concepts to open channel flow through vegetation resulted in a collapse of data for vegetative drag coefficient for the various vegetation types and densities into a single relationship when plotted against vegetative stem Reynolds number. Point velocity and turbulence intensity profiles at different locations in the vegetative filter were recorded with an acoustic Doppler velocimeter to observe the turbulence structure of the flow and its effects on vegetative drag and settling of sediment. A sediment slurry consisting of a suspension of fine sand was fed into the flume, and an automated sampler was used to measure suspended sediment concentrations along the vegetative filter length for a series of discharges from which sediment flux and trap efficiency could be determined. Experimental data for trap efficiency were plotted against a dimensionless settling efficiency for each type of vegetation and density. These relationships, along with the one developed for the coefficient of drag, were applied in a numerical design technique that allows designers to determine the flow depth, velocity and trap efficiency of a vegetative filter of known dimensions for a given flow rate, sediment grain size distribution, slope, and vegetation density. In a typical design example, the combined trap efficiency proved that a seep berm followed by a vegetative filter can be a very effective erosion control measure.
30
Scholes, Lian N. L. "The use of constructed wetlands for the treatment of urban runoff". Thesis, Middlesex University, 1999. http://eprints.mdx.ac.uk/13373/.
Testo completoAbstract (sommario):
In 1995, the Environment Agency for England and Wales developed urban runoff treatment wetlands at two selected locations in Outer London. The systems have been monitored for a wide range of parameters including heavy metals, suspended solids and BOD over a period of two years. Seven storm events were also monitored. The ability of micro-organisms, isolated from the rhizosphere of wetland plants collected at both systems, to tolerate and accumulate heavy metals has also been investigated. This study has demonstrated that constructed wetland treatment systems are capable of reducing the pollutant loadings associated with urban runoff, and that such systems can be successfully established within urban areas. During dry weather, pollutant concentrations and loadings were typically low and associated removal efficiencies highly variable. However, during storm events, pollutant loadings increased and removal efficiencies improved, with mean removal efficiencies of 71% for Pb and 81% for Cr at the Dagenham wetland. An exception to this was for suspended solids which showed an overall increase of 99% during storm events. Several design and operational issues have been identified and addressed during the course of the monitoring programme, and recommendations for the improved design and operation of urban runoff treatment wetland systems have been made. A range of micro-organisms, isolated from both wetland systems, were able to tolerate elevated Zn and Pb concentrations. Two strains (Beauveria bassiana and Rhodotorula mucilaginosa) were selected for further work. Both strains could accumulate Zn and Pb, with B. bassiana showing a high capacity to bind Pb (maximum concentration of 136mgPb/g cells dry weight). Comparison of the growth of B. bassiana at 4°C and 30°C suggested that processes of microbial metal accumulation may occur throughout the year in treatment wetlands. The presence of Pb inside hyphae of B. bassiana, associated with hyphae walls and in the surrounding medium was confirmed. This study has found that micro-organisms isolated from urban runoff treatment wetlands can tolerate and accumulate Zn and Pb, and the application of these results to wetland treatment processes is discussed.
31
Green, Daniel. "Understanding urban rainfall-runoff responses using physical and numerical modelling approaches". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33530.
Testo completoAbstract (sommario):
This thesis provides a novel investigation into rainfall-runoff processes occurring within a unique two-tiered depth-driven overland flow physical modelling environment, as well as within a numerical model context where parameterisation and DEM/building resolution influences have been investigated using an innovative de-coupled methodology. Two approaches to simulating urban rainfall-runoff responses were used. Firstly, a novel, 9 m2 physical modelling environment consisting of a: (i) a low-cost rainfall simulator component able to simulate consistent, uniformly distributed rainfall events of varying duration and intensity, and; (ii) a modular plot surface layer was used. Secondly, a numerical hydroinundation model (FloodMap2D-HydroInundation) was used to simulate a short-duration, high intensity surface water flood event (28th June 2012, Loughborough University campus). The physical model showed sensitivities to a number of meteorological and terrestrial factors. Results demonstrated intuitive model sensitivity to increasing the intensity and duration of rainfall, resulting in higher peak discharges and larger outflow volumes at the model outflow unit, as well as increases in the water depth within the physical model plot surface. Increases in percentage permeability were also shown to alter outflow flood hydrograph shape, volume, magnitude and timing due to storages within the physical model plot. Thus, a reduction in the overall volume of water received at the outflow hydrograph and a decrease in the peak of the flood event was observed with an increase in permeability coverage. Increases in the density of buildings resulted in a more rapid receding limb of the hydrograph and a steeper rising limb, suggesting a more rapid hydrological response. This indicates that buildings can have a channelling influence on surface water flows as well as a blockage effect. The layout and distribution of permeable elements was also shown to affect the rainfall-runoff response recorded at the model outflow, with downstream concentrated permeability resulting in statistically different hydrograph outflow data, but the layout of buildings was not seen to result in significant changes to the outflow flood hydrographs; outflow hydrographs appeared to only be influenced by the actual quantity and density of buildings, rather than their spatial distribution and placement within the catchment. Parameterisation of hydraulic (roughness) and hydrological (drainage rate, infiltration and evapotranspiration) model variables, and the influence of mesh resolution of elevation and building elements on surface water inundation outputs, both at the global and local level, were studied. Further, the viability of crowdsourced approaches to provide external model validation data in conjunction with dGPS water depth data was assessed. Parameterisation demonstrated that drainage rate changes within the expected range of parameter values resulted in considerable losses from the numerical model domain at global and local scales. Further, the model was also shown to be moderately sensitive to hydraulic conductivity and roughness parameterisation at both scales of analysis. Conversely, the parameterisation of evapotranspiration demonstrated that the model was largely insensitive to any changes of evapotranspiration rates at the global and local scales. Detailed analyses at the hotspot level were critical to calibrate and validate the numerical model, as well as allowing small-scale variations to be understood using at-a-point hydrograph assessments. A localised analysis was shown to be especially important to identify the effects of resolution changes in the DEM and buildings which were shown to be spatially dependent on the density, presence, size and geometry of buildings within the study site. The resolution of the topographic elements of a DEM were also shown to be crucial in altering the flood characteristics at the global and localised hotspot levels. A novel de-coupled investigation of the elevation and building components of the DEM in a strategic matrix of scenarios was used to understand the independent influence of building and topographic mesh resolution effects on surface water flood outputs. Notably, the inclusion of buildings on a DEM surface was shown to have a considerable influence on the distribution of flood waters through time (regardless of resolution), with the exclusion of buildings from the DEM grid being shown to produce less accurate results than altering the overall resolution of the horizontal DEM grid cells. This suggests that future surface water flood studies should focus on the inclusion and representation of buildings and structural features present on the DEM surface as these have a crucial role in modifying rainfall-runoff responses. Focus on building representation was shown to be more vital than concentrating on advances in the horizontal resolution of the grid cells which make up a DEM, as a DEM resolution of 2 m was shown to be sufficiently detailed to conduct the urban surface water flood modelling undertaken, supporting previous inundation research.
32
Zhang, Lan. "Transport and capture of bacteria from urban stormwater runoff using bioretention". College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8816.
Testo completoAbstract (sommario):
Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Civil and Environmental Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
33
Luckemeier, Richard Ewald 1948. "A rainfall-runoff model for an urban watershed in Tucson, Arizona". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277165.
Testo completoAbstract (sommario):
The U.S. Geological Survey and the City of Tucson, Arizona, have been collecting rainfall and runoff data on several watersheds in the Tucson area for several years. Among the purposes of this project is to use the data to test rainfall-runoff models in an effort to find one to successfully simulate flood flows in Tucson. One such model, the Distributed Routing Rainfall-Runoff Model (DR3M), was tested using data collected on Rob Wash in Tucson. It was found DR3M performs about as well as it does in other parts of the United States, although it tends to underestimate flood flows for large storms and overestimate flows for smaller storms. Unique features with regard to the hydrology of urban Tucson require special attention when using DR3M; these features are associated with the nature of dry washes and summer rainfall in Tucson. Experience indicates DR3M is not truly a deterministic model.
34
McKinney, Steven B. "Substitute costs a method for determining ecological service values in stormwater management /". Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009p/mckinney.pdf.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--University of Alabama at Birmingham, 2009.Additional advisors: Robert Angus, Paul D. Blanchard, Sarah Culver, Alan Shih. Description based on contents viewed June 3, 2009; title from PDF t.p. Includes bibliographical references (p. 48-51).
35
Macdonald, Kirsteen C. B. "The effectiveness of certain sustainable urban drainage systems in controlling flooding and pollution from urban runoff". Thesis, Abertay University, 2003. https://rke.abertay.ac.uk/en/studentTheses/b6fdd917-aff9-42a2-9b14-089989b57dd2.
Testo completoAbstract (sommario):
The research presented in this thesis addressed the performance of Sustainable Urban Drainage Systems (SUDS) at three sites in Scotland - a porous paved car park and two swales. It is the first research to provide results for such systems in the UK and also the first direct comparison between SUDS and traditional systems in situ. The aim of developing guidance on effectiveness and synthesising design recommendations has been achieved with the integration of hydrological and water quality studies together with modeling. Monitoring data and information were analysed on both a site-by-site basis and as a comparison between sites. Hydrological and water quality data were collected at each site. Key hydraulic parameters examined include percentage runoff, initial runoff loss, peak flow reduction and lag time. The term Benefit Factor has been introduced as a volumetric measure used to summarise the hydraulic benefit gained by installing SUDS, as no comparable terminology has yet been used elsewhere. The water quality parameters include physical/ chemical, hydrocarbons and metals. All three sites had low levels of pollution with little scope for water quality improvement, however the changes in water quality did indicate the different processes occurring within the systems. Computer models were built for the porous paving installation and one of the swales, further to understand the processes of source control and to analyse the systems. Hydraulic capacity exceedence criteria were investigated using design storms, and finally the models were used to evaluate improvements to design detailing. The results of this research have shown that, despite being under-designed according to current guidance, all three sites performed very favourably. The performance of porous paving and swales can be similar depending on design and detailing. A number of design recommendations are made as a result of observations and sensitivity analysis, and these should be considered in conjunction with current guidance.
36
Bailey, Chrissy. "Low impact development barriers towards sustainable stormwater management practices in the Puget Sound region /". Online pdf file accessible through the World Wide Web, 2003. http://archives.evergreen.edu/masterstheses/Accession86-10MES/2003Bailey_CMESThesis.pdf.
Testo completo
37
Grehl, Elaine. "The design and implementation of a rain garden at the University of Delaware a case study /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.33 Mb., p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1435834.
Testo completo
38
Lebarron, Elise. "A policy roadmap for low impact development in Spokane, Washington". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Spring2007/e_lebarron_041007.pdf.
Testo completo
39
Owen, Polly C. "The effects of rainfall runoff from urban and rural watersheds on trihalomethane precursors in streams". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06302009-040240/.
Testo completo
40
Watts, Sarah E. J. "The impact of urban runoff on estuarine pollution, the River Lagan, Belfast". Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263580.
Testo completo
41
Wright, Alan. "The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005491.
Testo completoAbstract (sommario):
The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
42
Appel, Patrick L. "Use of Automated Sampler to Characterize Urban Stormwater Runoff in Pecan Creek". Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2681/.
Testo completoAbstract (sommario):
The purpose of this study was to use the Global Water Stormwater Sampler SS201 to characterize the urban runoff in Pecan Creek. Location of the samplers was influenced by land use and ease of installation. Determination of the constituents for analysis was modeled after those used in the NPDES permit for seven cities within the Dallas/Ft.Worth metroplex. Some metals, notably cadmium and arsenic, exceeded the U.S. EPA's MCL's. Statistical analysis revealed first flush samples to be significantly more concentrated than composite samples. Minimum discharge loadings were found to be significantly lower than maximum discharge loadings. Additionally there were significant differences of specific constituents between station locations and storm events.
43
Flint, Kelly Renee. "Water quality characterization of highway stormwater runoff from an ultra-urban area". College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/210.
Testo completoAbstract (sommario):
Thesis (M.S.) -- University of Maryland, College Park, 2004.Thesis research directed by: Dept. of Civil and Environmental Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
44
Lormand, Jeffery Robert 1960. "The effects of urban vegetation on stormwater runoff in an arid environment". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/192003.
Testo completoAbstract (sommario):
The effects of urban vegetation on storm water runoff were documented using a model based on the curve number technique developed by the Soil Conservation Service. The study was conducted in three Parts. The first section analyzes the percentages of land use and land cover types found in a primarily residential watershed located in Tucson, Arizona. The second section evaluated four models for the ability to accurately predict storm water runoff. The final section analyzed the effects of four canopy cover scenarios: 0%, 21% (existing), 35% and 50% on the volume of stormwater runoff. Land cover percentages were found to differ from other cities in three areas: tree canopy, bare soil, and impervious surface. Runoff models that have curve numbers which have been lumped or weighted underestimated runoff while the model which summed the volumes of runoff from each cover type overestimated runoff. Tree canopy cover was found to not have a large impact on urban storm water runoff. Existing canopy cover reduced runoff by 3.8%. By increasing canopy cover from 0% to 50%, annual reductions in runoff of about 8.1% could be expected.
45
Herbst, Annemarie H. "Regulating farm nutrient runoff : Maryland's experience with the Water Quality Improvement Act". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33409.
Testo completoAbstract (sommario):
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2005.Includes bibliographical references (p. 66-76).
Federal and state programs designed to address nonpoint agricultural nutrient pollution rely almost exclusively on voluntary programs and financial incentives to encourage farmers to adopt nutrient management plans and other best management practices. In 1998, after highly publicized fish kills highlighted shortcomings in the voluntary approach, Maryland adopted the nation's strictest and most comprehensive nutrient management regulations. Seven years later, a majority of farmers are not in compliance with the law. This thesis examines the Maryland Department of Agriculture's implementation of the Water Quality Improvement Act. I find the department has continued to adhere to a voluntary approach to nutrient management. As a result, farmer practices are largely unchanged and the efficacy of a mandatory approach remains untested.
by Annemarie H. Herbst.
M.C.P.
46
Fahy, Benjamin. "Evaluating the Impact and Distribution of Stormwater Green Infrastructure on Watershed Outflow". PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/4732.
Testo completoAbstract (sommario):
Green Stormwater Infrastructure (GSI) has become a popular method for flood mitigation as it can prevent runoff from entering streams during heavy precipitation. In this study, a recently developed neighborhood in Gresham, Oregon hosts a comparison of various GSI projects on runoff dynamics. The study site includes dispersed GSI (rain gardens, retention chambers, green streets) and centralized GSI (bioswales, detention ponds, detention pipes). For the 2017-2018 water year, hourly rainfall and observed discharge data is used to calibrate the EPA's Stormwater Management Model to simulate rainfall-runoff dynamics, achieving a Nash-Sutcliffe efficiency of 0.75 and Probability Bias statistic of 3.3%. A synthetic scenario analysis quantifies the impact of the study site GSI and compares dispersed and centralized arrangements. Each test was performed under four precipitation scenarios (of differing intensity and duration) for four metrics: runoff ratio, peak discharge, lag time, and flashiness. Design structure has significant impacts, reducing runoff ratio 10 to 20%, reducing peak discharge 26 to 68%, and reducing flashiness index 56 to 70%. There was a reverse impact on lag time, increasing it to 50 to 80%. Distributed GSI outperform centralized structures for all metrics, reducing runoff ratio 22 to 32%, reducing peak discharge 67 to 69%, increasing lag time 133 to 500%, and reducing flashiness index between 32 and 62%. This research serves as a basis for researchers and stormwater managers to understand potential impact of GSI on reducing runoff and downstream flooding in small urban watersheds with frequent rain.
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Woodson, David. "Precipitation Estimation Methods in Continuous, Distributed Urban Hydrologic Modeling". Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/90373.
Testo completoAbstract (sommario):
Quantitative precipitation estimation (QPE) remains a key area of uncertainty in hydrological modeling, particularly in small, urban watersheds which respond rapidly to precipitation and can experience significant spatial variability in rainfall fields. Few studies have compared QPE methods in small, urban watersheds, and studies which have examined this topic only compared model results on an event basis using a small number of storms. This study sought to compare the efficacy of multiple QPE methods when simulating discharge in a small, urban watershed on a continuous basis using an operational hydrologic model and QPE forcings. The Research Distributed Hydrologic Model (RDHM) was used to model a basin in Roanoke, Virginia, USA forced with QPEs from four methods: mean field bias (MFB) correction of radar data, kriging of rain gauge data, uncorrected radar data, and a basin-uniform estimate from a single gauge inside the watershed. Based on comparisons between simulated and observed discharge at the basin outlet for a 6-month period in 2018, simulations forced with the uncorrected radar QPE had the highest accuracy, as measured by root mean square error (RMSE) and peak flow relative error, despite systematic underprediction of the mean areal precipitation (MAP). Simulations forced with MFB corrected radar data consistently and significantly overpredicted discharge but had the highest accuracy in predicting the timing of peak flows.Master of Science
Estimating the amount of rain that fell during a precipitation event remains a key source of error when predicting how much stormwater runoff will be produced, particularly in small, urban watersheds which respond rapidly to precipitation and can experience significant spatial variability in rainfall distribution. Rainfall estimation in small, urban watersheds has received relatively little attention, and studies which have examined this topic have generally only examined a small number of discrete storm events. This study sought to compare the efficacy of multiple precipitation estimation methods when simulating discharge in a small, urban watershed on a continuous basis using an operational hydrologic model and precipitation inputs. The Research Distributed Hydrologic Model (RDHM), commonly used by the National Weather Service, was used to model a basin in Roanoke, Virginia, USA forced with rainfall estimates from four methods: mean field bias (MFB) correction of radar data, kriging of rain gauge data, uncorrected radar data, and a basin-uniform estimate from a single gauge inside the watershed. Based on comparisons between simulated and observed discharge at the basin outlet for a 6-month period in 2018, simulations forced with the uncorrected radar QPE had the highest accuracy, as measured by several performance statistics, despite systematic underprediction of actual precipitation. Simulations forced with MFB corrected radar data consistently and significantly overpredicted discharge but had the highest accuracy in predicting the timing of peak flows.
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Waters, Summer, Kitt Farrell-Poe e Kristen Wagner. "When it Rains it Runs Off: Runoff and Urbanized Areas in Arizona". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/146927.
Testo completoAbstract (sommario):
5 pp.Urban run-off is created by rain, snowmelt, or irrigation water flowing across sidewalks, drive ways, roadways, and other surfaces into storm drains. All storm drains empty into rivers or river beds, lakes, streams, washes, and other storage areas often without treatment. The Urban Run-off (Non-point Source Pollution) Tip Sheet will educate the reader on urban run-off and associated water pollution. The tip sheet explains the causes, effects, and sources of non-point source pollution. It also provides information on what can be done to prevent urban run-off and water pollution. It includes both general information as well as information specific to Maricopa County.
49
Segarra, Rafael Ivan. "A statistical approach to urban stormwater detention planning". Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/81046.
Testo completoAbstract (sommario):
A statistical model has been developed to study the long-term behaviour of a stormwater detention unit. This unit stores a portion of the incoming runoff, corresponding to the empty space available in the unit, from which runoff is pumped to a treatment plant. The objective is to avoid, as much as possible, the discharge of untreated runoff to receiving bodies of water.
The model was developed by considering the arrival of independent runoff events at the urban catchment. The process variables of event depth, duration, and interevent time were treated as independent, identically distributed random variables. A storage equation was formulated from which the probability of detention unit overflow was obtained. With this distribution it was possible to define the trap efficiency of the unit in terms of the long-term fraction of the runoff volume trapped by the storage unit.
The trap efficiency expressions define storage/ treatment isoquants, which represent the combinations of storage capacity, treatment rate, and the sewer system runoff trapping capacity, which provide a fixed level of runoff control.
A pollutant load model was also formulated, based on a first-order washoff model. This model was used to define pollutant control isoquants.
Optimal values of the required storage capacity and treatment rate were obtained by treating the isoquants as production functions. Applying the results of production function theory, a cost minimization problem was solved for the value of the storage capacity and treatment rate, for prescribed runoff and pollutant trap efficiency levels.
The results obtained with the statistical model compared well with results obtained from major simulation models.
The statistical approach offers an advantage in that no simulation is required to obtain the isoquants, as the expressions are analytical, thus greatly simplifying the optimization process. Also, the evaluation of the storage unit pollutant trap efficiency can be easily evaluated for any type of pollutant whose washoff rate is known.Ph. D.
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Fulkerson, Mark. "ATMOSPHERIC MERCURY DEPOSITION IN AN URBAN ENVIRONMENT". Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2628.
Testo completoAbstract (sommario):
Atmospheric mercury deposition, known to be a major source of mercury to aquatic and terrestrial environments, was studied at an urban site in Orlando, FL. Precipitation sampling was conducted from September 2003 to May 2006 at a Mercury Deposition Network site located on the University of Central Florida campus. Weekly rainfall and mercury wet deposition data were gathered from this site, which provided the framework of data for this study. Historical mercury wet deposition data from several sites in Florida were used to develop a regression model to predict mercury deposition at any location in Florida. Stormwater runoff from a 2-acre impervious surface at this study area was monitored during the spring and summer of 2005. Runoff water quality was analyzed to characterize mercury dry deposition. Atmospheric monitoring was also conducted during this period to study the interaction of atmospheric constituents on wet and dry deposition patterns. Spatial and seasonal trends for the entire state suggest 80% of Florida's rainfall and mercury deposition occur during the wet season. A strong linear correlation was established between rainfall depth and mercury deposition (R2 = 0.8). Prediction equations for the entire state, for both wet and dry seasons, were strongly correlated with measured data. The results of two unique methods to quantify dry deposition were similar at this site during this study period. Runoff monitored at this site contained significant levels of mercury, primarily in particulate form (58%). The vast majority of particulate mercury was flushed from the surface during storm events, while significant dissolved fractions remained. Runoff mercury concentrations were consistently higher than rainfall mercury, suggesting dry deposition accounted for 22% of total mercury in runoff. Atmospheric monitoring at this location showed gaseous elemental mercury was the dominant form (99.5%) followed by reactive gaseous mercury (0.3%) and particulate mercury (0.2%). Comparison of the contributions of wet and dry deposition suggested 80% of total mercury deposition was wet deposited during this study, while dry deposition accounted for the remaining 20%. Statistical correlations revealed rainfall scavenging of reactive gaseous mercury was the main factor controlling dry deposition.Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering