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1
Grabau, Matthew R., Richard H. Hawkins, Kevin E. Verweire e Donald C. Slack. "Variety of Antecedent Runoff Conditions for Rainfall-Runoff with the Curve Number Method". Arizona-Nevada Academy of Science, 2009. http://hdl.handle.net/10150/296695.
Testo completo
2
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
3
Nelson, Stephen Swanson. "Performance evaluation of cold weather infiltration facilities". Online access for everyone, 2006. http://www.dissertations.wsu.edu/Thesis/Summer2006/s_nelson_082906.pdf.
Testo completo
4
Kary, Daniel James. "Residential Development and Stormwater Runoff". Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/KaryD2011.pdf.
Testo completo
5
Sullivan, J. H. "Metallic runoff from coated steels". Thesis, Swansea University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639132.
Testo completoAbstract (sommario):
An investigation was carried out to assess levels of metallic runoff, particularly zinc, from the surface and cut-edges of a variety of commercial coated steels in order to ascertain potential environmental effects in line with the ongoing EU risk assessment into zinc (1995). Zinc runoff was monitored from the surfaces of a range of zinc-coated steels with sealed edges over 19 months at two UK weathering sites. The composition of the zinc coating is crucial in determining materials performance and rainfall levels are critical in determining runoff quantity. Observed zinc runoff levels are generally below the permissible drinking water level for humans but runoff levels in the harshest environment exceed this maximum for some materials during the exposure. A range of organically coated galvanised steels were exposed for 27 months at three UK weathering sites with a large cut-edge length to assess runoff from such edges. Runoff was high in initial months with zinc levels reducing with time due to the build up/action of corrosion products and corrosion inhibitors. Zinc levels were below the permissible drinking water level. Zinc runoff measured over 3 months can more accurately predict long-term organic coating delamination than salt spray and prohesion testing. Accelerated laboratory tests using a distilled water electrolyte were developed that predict long-term external weathering runoff from panels of a range of coated steels. The angle of panel, electrolyte flow rate and wet/dry cycles affect the runoff levels of such tests. The corrosion mechanisms of a variety of zinc-coated steels have been examined using the scanning vibrating electrode technique (SVET) in 0.1%NaCl. The corrosion behaviour of a coating is related to its structure and composition. The SVET has been used to assess total zinc loss from coatings during corrosion and has been confirmed using ICP-MS analysis. The predicted zinc losses from the SVET were used to model up to 12 months external weathering behaviour for the zinc-coated steels.
6
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.
7
Wang, H. "Precipitation-runoff relationships for palaeohydrology". Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382996.
Testo completo
8
Riverso, Carlo. "Calibration of rainfall-runoff models". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2619/.
Testo completo
9
Dean, Kyla. "Phosphorus runoff to Clear Creek". Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/943.
Testo completoAbstract (sommario):
Phosphorus is a nutrient crucial to row crop production, but phosphorus runoff from fields to nearby surface waters is a persistent problem that threatens the quality of rivers and streams. This is especially true for Iowa with its abundance of agricultural practices. In order to better understand the phosphorus dynamics of a watershed with agricultural land use, Clear Creek in Iowa was studied. Total, dissolved, and suspended reactive phosphorus concentrations were measured and mass fluxes were calculated. Through this research it was determined that most of the mass of phosphorus in Clear Creek is transferred during high flow events and is attached to solids. The headwaters area of this stream was found to be a major source of phosphorus due to the abundance of row crops and steeply sloped land.
10
Abushandi, Eyad. "Rainfall-runoff modeling in arid areas". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-68530.
Testo completoAbstract (sommario):
The Wadi Dhuliel catchment/ North east Jordan, as any other arid area has distinctive hydrological features with limited water resources. The hydrological regime is characterized by high variability of temporal and spatial rainfall distributions, flash floods, absence of base flow, and high rates of evapotranspiration. The aim of this Ph.D. thesis was to apply lumped and distributed models to simulate stream flow in the Wadi Dhuliel arid catchment. Intensive research was done to estimate the spatial and temporal rainfall distributions using remote sensing. Because most rainfall-runoff models were undertaken for other climatic zones, an attempt was made to study limitations and challenges and improve rainfall-runoff modeling in arid areas in general and for the Wadi Dhuliel in particular.
The thesis is divided into three hierarchically ordered research topics. In the first part and research paper, the metric conceptual IHACRES model was applied to daily and storm events time scales, including data from 19 runoff events during the period 1986-1992. The IHACRES model was extended for snowfall in order to cope with such extreme events. The performance of the IHACRES model on daily data was rather poor while the performance on the storm events scale shows a good agreement between observed and simulated streamflow. The modeled outputs were expected to be sensitive when the observed flood was relatively small. The optimum parameter values were influenced by the length of a time series used for calibration and event specific changes.
In the second research paper, the Global Satellite Mapping of Precipitation (GSMaP_MVK+) dataset was used to evaluate the precipitation rates over the Wadi Dhuliel arid catchment for the period from January 2003 to March 2008. Due to the scarcity of the ground rain gauge network, the detailed structure of the rainfall distribution was inadequate, so an independent from interpolation techniques was used. Three meteorological stations and six rain gauges were used to adjust and compare with GSMaP_MVK+ estimates. Comparisons between GSMaP_MVK+ measurements and ground rain gauge records show distinct regions of correlation, as well as areas where GSMaP_MVK+ systematically over- and underestimated ground rain gauge records. A multiple linear regression (MLR) model was used to derive the relationship between rainfall and GSMaP_MVK+ in conjunction with temperature, relative humidity, and wind speed. The MLR equations were defined for the three meteorological stations. The ‘best’ fit of the MLR model for each station was chosen and used to interpolate a multiscale temporal and spatial distribution. Results show that the rainfall distribution over the Wadi Dhuliel is characterized by clear west-east and north-south gradients. Estimates from the monthly MLR model were more reliable than estimates obtained using daily data. The adjusted GSMaP_MVK+ dataset performed well in capturing the spatial patterns of the rainfall at monthly and annual time scales, while daily estimation showed some weakness for light and moderate storms.
In the third research paper, the HEC-HMS and IHACRES rainfall runoff models were applied to simulate a single streamflow event in the Wadi Dhuliel catchment that occurred in 30-31.01.2008. Both models are considered suitable for arid conditions. The HEC-HMS model application was done in conjunction with the HEC-GeoHMS extension in ArcView 3.3. Streamflow estimation was performed on hourly data. The aim of this study was to develop a new framework of rainfall-runoff model applications in arid catchment by integrating a re-adjusted satellite derived rainfall dataset (GSMaP_MVK+) to determine the location of the rainfall storm. Each model has its own input data sets. HEC-HMS input data include soil type, land use/land cover map, and slope map. IHACRES input data sets include hourly rainfall and temperature. The model was calibrated and validated using observed stream flow data collected from Al-Za’atari discharge station. IHACRES shows some weaknesses, while the flow comparison between the calibrated streamflow results agrees well with the observed streamflow data of the HEC-HMS model. The Nash-Sutcliffe efficiency (Ef) for both models was 0.51, and 0.88 respectively. The application of HEC-HMS model in this study is considered to be satisfactory.
11
Zelelew, Mulugeta. "Improving Runoff Estimation at Ungauged Catchments". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for vann- og miljøteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19675.
Testo completoAbstract (sommario):
Water infrastructures have been implemented to support the vital activities of human society. The infrastructure developments at the same time have interrupted the natural catchment response characteristics, challenging society to implement effective water resources planning and management strategies. The Telemark area in southern Norway has seen a large number of water infrastructure developments, particularly hydropower, over more than a century. Recent developments in decision support tools for flood control and reservoir operation has raised the need to compute inflows from local catchments, most of which are regulated or have no observed data. This has contributed for the motivation of this PhD thesis work, with an aim of improving runoff estimation at ungauged catchments, and the research results are presented in four manuscript scientific papers. The inverse distance weighting, inverse distance squared weighting, ordinary kriging, universal kriging and kriging with external drift were applied to analyse precipitation variability and estimate daily precipitation in the study area. The geostatistical based univariate and multivariate map-correlation concepts were applied to analyse and physically understand regional hydrological response patterns. The Sobol variance based sensitivity analysis (VBSA) method was used to investigate the HBV hydrological model parameterization significances on the model response variations and evaluate the model’s reliability as a prediction tool. The HBV hydrological model space transferability into ungauged catchments was also studied. The analyses results showed that the inverse distance weighting variants are the preferred spatial data interpolation methods in areas where relatively dense precipitation station network can be found. In mountainous areas and in areas where the precipitation station network is relatively sparse, the kriging variants are the preferred methods. The regional hydrological response correlation analyses suggested that geographic proximity alone cannot explain the entire hydrological response correlations in the study area. Besides, when the multivariate map-correlation analysis was applied, two distinct regional hydrological response patterns - the radial and elliptical-types were identified. The presence of these hydrological response patterns influenced the location of the best-correlated reference streamgauges to the ungauged catchments. As a result, the nearest streamgauge was found the best-correlated in areas where the radial-type hydrological response pattern is the dominant. In area where the elliptical-type hydrological response pattern is the dominant, the nearest reference streamgauge was not necessarily the best-correlated. The VBSA verified that varying up to a minimum of four to six influential HBV model parameters can sufficiently simulate the catchments' responses characteristics when emphasis is given to fit the high flows. Varying up to a minimum of six influential model parameters is necessary to sufficiently simulate the catchments’ responses and maintain the model performance when emphasis is given to fit the low flows. However, varying more than nine out of the fifteen HBV model parameters will not make any significant change on the model performance. The hydrological model space transfer study indicated that estimation of representative runoff at ungauged catchments cannot be guaranteed by transferring model parameter sets from a single donor catchment. On the other hand, applying the ensemble based model space transferring approach and utilizing model parameter sets from multiple donor catchments improved the model performance at the ungauged catchments. The result also suggested that high model performance can be achieved by integrating model parameter sets from two to six donor catchments. Objectively minimizing the HBV model parametric dimensionality and only sampling the sensitive model parameters, maintained the model performance and limited the model prediction uncertainty.
12
Goodrich, David Charles. "Basin Scale and Runoff Model Complexity". Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/614028.
Testo completoAbstract (sommario):
Distributed Rainfall-Runoff models are gaining widespread acceptance; yet, a
fundamental issue that must be addressed by all users of these models is definition
of an acceptable level of watershed discretization (geometric model complexity). The
level of geometric model complexity is a function of basin and climatic scales as well
as the availability of input and verification data. Equilibrium discharge storage is
employed to develop a quantitative methodology to define a level of geometric model
complexity commensurate with a specified level of model performance. Equilibrium
storage ratios are used to define the transition from overland to channel -dominated
flow response. The methodology is tested on four subcatchments in the USDA -ARS
Walnut Gulch Experimental Watershed in Southeastern Arizona. The catchments
cover a range of basins scales of over three orders of magnitude. This enabled a
unique assessment of watershed response behavior as a function of basin scale.
High quality, distributed, rainfall -runoff data was used to verify the model (KINEROSR). Excellent calibration and verification results provided confidence in
subsequent model interpretations regarding watershed response behavior. An
average elementary channel support area of roughly 15% of the total basin area is
shown to provide a watershed discretization level that maintains model performance
for basins ranging in size from 1.5 to 631 hectares. Detailed examination of
infiltration, including the role and impacts of incorporating small scale infiltration
variability in a distribution sense, into KINEROSR, over a range of soils and
climatic scales was also addressed. The impacts of infiltration and channel losses
on runoff response increase with increasing watershed scale as the relative influence
of storms is diminished in a semiarid environment such as Walnut Gulch. In this
semiarid environment, characterized by ephemeral streams, watershed runoff
response does not become more linear with increasing watershed scale but appears
to become more nonlinear.
13
Al-Qurashi, Aisha Mufti Al-Sayyid Hassan. "Rainfall-runoff modelling in arid areas". Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/8860.
Testo completoAbstract (sommario):
Arid areas have distinctive hydrological features substantially different from those of humid areas. The high temporal and spatial distribution of the ra;infall, flash floods, absence of base flow, sparsity of plant cover, high transmission losses, high amounts of evaporation and evapotranspiration and the general climatologies are examples of such differences. The aim of this Ph.D. research is to use advanced tools of model analysis to test some of the current models that consider arid area hydrological characteristics. As most models were mainly developed for other regions, an attempt is made to study their limitations using Omani hydrological data, providing some guidelines for improved rainfall-runoff modelling in arid areas in general and Oman in particular. Two different types of models were selected for this research; KINEROS, which is an event based, semi-distributed, physically-based model that is considered suitable to be used for arid area conditions, and, which is continuous, lumped, conceptual model. Two Omani catchments were selected to test the performance of the selected models and to identify the main uncertainties arising, to provide some recommendations regarding the suitability of these models or model types and how they might be improved, to highlight any further data that is required, and how uncertainties should be handled in model applications.
14
Price, Myra Ann. "Seasonal Variation in Runoff Curve Number". Thesis, The University of Arizona, 1998. http://hdl.handle.net/10150/225411.
Testo completoAbstract (sommario):
The seasonal variation in rainfall - runoff response is investigated for about 300 small watersheds throughout the United States. Data from USDA research watersheds were used to define runoff Curve Number for ordered data sets by months. Three major patterns of cyclic variation are found and investigated: 1) distinct and well - defined seasonal variations as typified by forested watersheds in heavy rainfall zones; 2) mildly cyclic variation found typically in meadows and grasslands, and 3) non - cyclic or unidentifiable patterns, including those with insufficient seasonal data. The only pattern that may be present is the well-defined seasonal variation found so far only in forested watersheds. Regional characteristics were found for individual crop types. For the watersheds studied there seemed to be no difference in the variation between crops except for meadow during the summer. Some associated background factors are explored, including long-term and short-term antecedent rainfall.
15
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.
16
Skogley, C. David. "An investigation of the SCS runoff equation as a means of measuring and reducing runoff in residential development". Virtual Press, 1987. http://liblink.bsu.edu/uhtbin/catkey/543777.
Testo completoAbstract (sommario):
This study was undertaken to investigate and discuss the use of the soil conservation service runoff equation as a design guide for residential development design. The objectives of the study were (i) to determine the extent to which a hypothetical residential development scheme affected the site's runoff volume and peak discharge rate, (ii) to use the existing SCS runoff equation to predict hypothetical pre- and post-development runoff volumes and rates, (iii) to apply the above findings to a design revision of the residential site plan in order to produce less runoff modification as a result of the development. The Crapo Estate in Muncie, Indiana was chosen as the site for the study. Site analysis data and an initial design (Scheme A) from a fourth year undergraduate design studio were used with the runoff equation to predict pre- and post-development runoff volumes and rates. Curve number (CH) maps were then constructed by overlaying site land uses and soil types. These maps indicated where the site's most permeable soils were located according to land use, and were used in conjunction with the equation as a guide to the design of a second residential development. This second design (Scheme B) fulfilled all design requirements while producing a slightly smaller runoff modification than Scheme A.This study showed that residential development caused a substantial and measurable increase in both runoff volume and rate. The SCS runoff equation was useful for both accurate runoff measurement and as a means of guiding design decisions in order to reduce runoff in residential development.Department of Landscape Architecture
17
Loague, Keith M. "An assessment of rainfall-runoff modeling methodology". Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27131.
Testo completoAbstract (sommario):
This study reports model performance calculations for three event-based rainfall-runoff models on both real and synthetic data sets. The models include a regression model, a unit hydrograph model and a quasi-physically based model. The real data sets are for small upland catchments from the Washita River Experimental Watershed, Oklahoma; the Mahantango Creek Experimental Watershed, Pennsylvania; and the Hubbard Brook Experimental Forest, New Hampshire. The synthetic data sets are generated with a stochastic-conceptual rainfall-runoff simulator. Model performance is assessed for a verification period that is carefully distinguished from the calibration period. Performance assessment was carried out both in forecasting mode and in prediction mode. The results on the real data sets show surprisingly poor forecasting efficiencies for all models on all data sets. The unit hydrograph model and the quasi-physically based model have little forecasting power; the regression model is marginally better. The performance of the models in prediction mode is better. The regression model and the unit hydrograph model showed acceptable predictive power, but the quasi-physically based model produced acceptable predictions on only one of the three catchments. The performance of the regression and unit hydrograph models, in both forecasting and prediction modes, for synthetic data is much better than for the real catchments. The performance of the quasi-physically based model on a synthetic data set is surprisingly poor. Supplemental data gathered from the Oklahoma catchment was used for a spatial variability analysis of steady-state infiltration rates. These data were then used to re-excite the quasi-physically based model; the new information resulted in improved model performance. The concept of space-time tradeoffs across the hydrologic data sets of competing models is introduced and tested. Results show the existence of space-time tradeoffs within model data sets but not across model data sets. It is the belief of the author that the primary barrier to successful application of physically based models in the field lies in the scale problems that are associated with the unmeasurable spatial variability of rainfall and soil hydraulic properties. The fact that simpler, less data intensive models provided as good or better predictions than a physically based model is food for thought. The model evaluation and space-time tradeoff experiments reported in this study are conceptually linked to data-worth analysis, network-design, and model-choice criteria for future studies.Graduate and Postdoctoral Studies
Graduate
18
Ligtenberg, Jora. "Runoff changes due to urbanization: A review". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-130507.
Testo completoAbstract (sommario):
Urbanization causes changes in the water balance. Focusing on runoff, the aim of this report was to determine how both the magnitude and the form of this component change with urbanization. Also, solutions for decreasing the possible problems related to an increase in surface runoff were examined. Solutions were studied for both a general European situation and for the specific case of the Netherlands. Already after converting a forested area into agriculture, the runoff becomes more prominent, at the expense of evaporation and infiltration. When developing further into an urban area, its importance increases even more. In the last few years, various scientists have come up with suggestions of reducing the risks caused by increased runoff. Some examples are increasing the infiltration capacity or storing the excess water in cities. Considering the predicted future climate scenarios, water storage seems to be the best option. In the Netherlands, expanding the areas for water storage is the main subject of governmental research at the moment. On top of that, researchers advice to cooperate more between different stakeholders when considering water management. The main findings are thus that runoff increases with an increasing imperviousness of the surface, and the best solution to avoid problems caused by this enhanced amount of runoff seems to be the storage of excess water in cities. This solution is valid for both a general situation and in the Netherlands.
19
Cheesman, Joanne E. "Modelling long-term runoff from upland catchments". Thesis, Manchester Metropolitan University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389290.
Testo completoAbstract (sommario):
The aim of the research contained in this thesis was to develop a model of long-term upland catchment runoff that can be used for ungauged catchments. This is a problem due to the complex spatial and temporal nature of runoff and the main contributing processes, precipitation (P) and evapotranspiration (Et). It is also a problem due to the lack of suitable data on which to base and test models of these processes, particularly in remote upland areas such as the north-west of England, the study area of this research. Long-term runoff is important since it represents the maximum rate at which water is available for human use and management, for assessment of water resource yield and for prediction of extreme events that are particularly important in respect to climate change. Methods currently in use by water companies in the UK, such as North West Water Limited (NWW), are inadequate since they fail to account for the spatial and temporal nature of runoff. New more reliable methods are therefore required which will equip water managers with flexible and responsive runoff modelling tools based upon routinely available data and that are sensitive to the complex physical nature of the processes involved. A physically based distributed runoff model was developed using GIS technology and spatial data to interpolate and extrapolate available point-based hydrometeorological data. The strategy required the development of models to derive areal representations of P and Et. For the P modelling several interpolation techniques and artificial neural network models were investigated. The results were evaluated against an independent data set. The results showed that a geostatistical interpolation technique, detrended Kriging, which uses pointbased precipitation and spatial elevation data provided the most accurate estimates when compared to other methods. The models of Et involved extrapolation of point-based Et values derived from the Penman-Monteith formula (Monteith, 1965), using spatial land cover data. A point-based temperature function model (Wright and Harding, 1993) that reduces the Penman estimates of Et for upland sites was spatially implemented using spatial temperature and elevation data. No independent data were available for model evaluation but first estimates of errors were gained through comparison of errors of runoff and precipitation estimates. Overall it was found that the most accurate E, model results were derived when the temperature function model was not implemented. Evidence of whether or not a lumped or heterogeneous land cover representation provided the more accurate results was unclear. Error evaluation and sensitivity analysis of the modelled runoff was carried out using measured runoff records and the results were compared to those produced using the North West Water model. It was found that the GIS-based model provided improved estimates of long-term average annual runoff for upland catchments. The largest component of the errors of the GIS-based method were associated with the Et estimates. This was principally a result of poor quality and limited availability of data for the study area. The research highlights many wider issues related to the use of GIS and spatial data for hydrological modelling.
20
Ringler, Simon. "First Flush Characterization of Storm Water Runoff". ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/537.
Testo completoAbstract (sommario):
This proposed research focused on the characterization of first flush in storm water runoff from elevated roadways, to assist the establishment of a storm water program and to facilitate the selection of treatment technology. Storm water runoff from highways transports a significant load of contaminants, especially heavy metals and particulate matter, to receiving waters. Heavy metals, either in dissolved or particulate bound phases, are unique in the fact that unlike organic compounds, they are not degraded in the environment. The objective was to develop a mass loading based diagram of the "first flush." In order to achieve this goal, a general characterization of the most important variables affecting “first flush†from elevated highways was necessarily. Also point this study is the requirement of a “first flush†treatment associated with storm water runoff from elevated highways. The test site was selected at the intersection of the Interstate-10 and Interstate- 610, Orleans Parish, New Orleans, Louisiana.
21
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.
22
Holden, Joseph. "Runoff production in blanket peat covered catchments". Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4264/.
Testo completoAbstract (sommario):
Although blanket peat covers many major headwater areas in Britain, runoff production within these upland catchments is poorly understood. This thesis examines runoff production mechanisms within the blanket peat catchments of the Moor House National Nature Reserve, North Pennines, UK. Catchments ranging from 11.4 km^ down to the hillslope and plot-scale are examined. Runoff from the monitored catchments was flashy. Lag times are short and rainwater is efficiently transported via quickflow- generating mechanisms such that flood peaks are high and low flows poorly maintained. Hillslope and plot-scale runoff measurements show that the flashy catchment response is the result of the dominance of overland flow. Typically 80 % of runoff is produced as overland flow. This occurs both on bare and vegetated surfaces. Most of the remaining runoff is generated from the upper 10 cm of the peat, except where well-connected macropore and pipe networks transfer flow through the lower layers. Below 10 cm depth the blanket peat matrix fails to contribute any significant runoff Thus most groundwater-based models of peat hydrological process are not readily applicable to these catchments. Suggestions that infiltration-excess overland flow may be largely responsible for the flashy regime of these upland catchments are not substantiated by the blanket peat infiltration data presented in this thesis. Monitoring of hillslope runoff mechanisms combined with rainfall simulation (at realistic intensities of 3-12 mm hr(^-1)) and tension- infiltrometer experiments shows that saturation-excess mechanisms dominate the response. Infiltration is relatively rapid in the upper peat layers until they become saturated and overland flow begins. High water tables result in rapid saturation of the peat mass such that even at low rainfall intensity runoff production is just as efficient as during high intensity events. While macropores have largely been ignored in blanket peat, results presented suggest that up to 30 % of runoff may be generated through them. Occasionally these macropore networks develop through the deeper peat such that runoff bypasses the matrix and runs off at depth from small outlets and larger pipe networks. Seasonal variations in runoff- generating processes can be exacerbated by drought which causes structural changes to the near-surface of the peat. This was found to result in enhanced infiltration and macropore flow which may encourage pipe network development. Flow has been monitored simultaneously from several natural pipes in a 0.4 km(^2) headwater catchment of the Tees. This catchment provides one of the few examples of pipeflow monitoring outside the shallow peaty-podzols of mid-Wales. Natural pipes are found throughout the soil profile and can be at depths of up to three metres. Ground penetrating radar was useful in identifying deep subsurface piping and suggestions are made for improvements to the application. The pipe networks were found to be complex and results demonstrate that outlet location and size may bear little relation to the form and depth of the pipe a short distance upslope. Pipes generally contribute less than 10 % to catchment runoff but on the rising and falling hydrograph limbs can contribute over 30 % to streamflow. Pipeflow lag times are short suggesting that both the shallow and deep pipes may be well connected to the surface. Thus while matrix runoff contributions at depth within the peat may be low, macropore flow mechanisms can be significant.
23
Penn, Chad John. "Phosphorus Losses in Runoff from Virginia Soils". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/28499.
Testo completoAbstract (sommario):
Previous research shows that dissolved P losses in runoff are well related to soil test P (STP), thus, various P loss prediction models incorporate the use of a STP vs. runoff DRP relationship. However, the relationship between STP and runoff DRP will vary based on soil type due to differences in soil properties. The purposes of the first two studies were to (i) investigate the effect of soil mineralogy on P sorption behavior and dissolved P in runoff and (ii) determine if any simple soil test extractions could indirectly take into account this effect of mineralogy.
Nine soil types from the Virginia Piedmont, Coastal Plain, and Ridge and Valley were collected and used in a rainfall simulation study. Phosphorus retention among separated clay fractions and whole soils were related to Al bearing minerals such as hydroxy-interlayered vermiculite (HIV), gibbsite, and amorphous Al. Samples dominated by kaolinite retained very little P. Application of these results to runoff data showed that soil types with a HIV:kaolinite ratio > 0.5 caused significantly less DRP in runoff for a given soil WSP level compared to soils with a ratio < 0.5.
The second study showed that the soil P vs runoff DRP relationships varied between physiographic provinces. Generally, the Coastal Plain soils resulted in a higher runoff DRP concentration for a given soil P level compared to Piedmont and Ridge and Valley soils. However, soil M3-P/Al resulted in one relationship with DRP for all three groups of soils. Results from the incubation study suggested that Al related P is more easily desorbed into solution compared to Fe related P.
The final study demonstrated that phytase enzyme and high available P corn supplements in poultry diets can reduce manure WSP and total P. Results from the runoff study showed that DRP losses were related to sediment losses which consisted of > 90% manure particles. Manure particles were directly deposited into the collection container followed by desorption of P based upon the WSP content of that manure type. The results emphasized best management practices that prevent direct loss of manure particles from soil into surface waters.Ph. D.
24
Silva, Vera Alexandra Félix Graça. "Contamination by wildfires runoff: effects of biofiltration". Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/9858.
Testo completoAbstract (sommario):
Mestrado em Biologia Aplicada - Ecologia, Biodiversidade e Gestão de EcossistemasTodos os anos, vastas áreas da região Mediterrânea são devastadas por incêndios florestais. Estes podem causar sérios impactos nos ecossistemas, existindo um interesse crescente sobre os seus efeitos na qualidade da água e no biota aquático. A partir de extratos aquosos de cinzas, que se assumiu simularem escorrências de uma área ardida, determinaram-se analiticamente vários metais e dezasseis hidrocarbonetos aromáticos policíclicos (HAPs). Paralelamente, foi realizada uma avaliação ecotoxicológica desses extratos aquosos de cinzas com quatro espécies standard, representando diferentes grupos funcionais e níveis tróficos. Os extratos aquosos de cinzas induziram uma redução no crescimento dos produtores primários Pseudokirchneriella subcapitata e Lemna minor, e inibiram a luminescência da bactéria Vibrio fischeri, enquanto não se verificou uma imobilização significativa em ensaios com o cladócero zooplanctónico Daphnia magna. Estes resultados são concordantes com a inconsistência que se verifica existir na literatura relativamente aos efeitos deletérios dos incêndios no ecossistema aquático. Esta avaliação ecotoxicológica permitiu construir uma base de análise comparativa com vista a responder à questão essencial que motivou este estudo: a presença do bivalve invasor Corbicula fluminea nos sistemas afetados poderá apoiar a mitigação dos potenciais efeitos dos incêndios florestais nas comunidades aquáticas? Neste contexto, o potencial biofiltrador desta espécie foi testado ao longo de sete dias, utilizando como modelo experimental os extratos aquosos de cinzas simulando escorrências de incêndios. Ao longo da experiência verificou-se a diminuição de metais (redução acima dos 70% para o Mn e Zn) e PAHs (redução de 50% nos valores de naftaleno na água e a bioconcentração de alguns elementos nos tecidos moles (especialmente Cu e Zn) e conchas das amêijoas (especialmente Mn). Paralelamente foi efetuada a avaliação ecotoxicológica dos extratos aquosos após a biofiltração, utilizando a mesma bateria de organismos acima descrita, e de um modo geral, observou-se uma diminuição da toxicidade dos extratos. Aquando da exposição aos extractos aquosos filtrados observou-se uma menor inibição do crescimento dos produtores primários (estatisticamente significativa na taxa de crescimento e no incremento total da biomassa de L. minor) bem como uma menor inibição da luminescência of V. fischeri (ou mesmo estimulação da luminescência em várias das concentrações testadas) e não se registaram efeitos tóxicos em D. magna. Estes resultados sugerem que os efeitos ecológicos nefastos da presença da espécie invasora C. fluminea podem, em cenários particulares, ser compensados em alguma medida por serviços adicionais que a espécie poderá prestar ao ecossistema.
Every year, large areas of the Mediterranean region are devastated by wildfires. Wildfires can cause serious impacts on terrestrial ecosystems but there is also a growing concern about their effects on surface water quality and on the aquatic biota. Aqueous extracts of ashes (AEA) were used in this study as an alternative for the runoff from a burnt area. Various metals and sixteen polycyclic aromatic hydrocarbons (PAHs) were analytically determined in the extracts. Their ecotoxicological assessment followed with four standard species representing different functional groups and trophic levels. The aqueous extracts of ashes induced a reduction in the growth of the primary producers Pseudokirchneriella subcapitata and Lemna minor, and inhibited the luminescence of the bacteria Vibrio fischeri but did not produce a significant immobilization in the cladoceran zooplankter Daphnia magna. These results reflected the inconsistency found in the literature on the deleterious effects of wildfires on aquatic ecosystems. This assessment comprised the first step of this study, which had, as overarching research question, whether the invasive bivalve Corbicula fluminea could mitigate the potential effects of wildfires on aquatic species. The biofiltration potential of this species was tested by exposing it to aqueous extract of ashes during a 7-day period, and by using the filtered solution in a second battery of ecotoxicological tests. Throughout the experiment there was a reduction of the concentration of the metals (more than 70% for Mn and Zn) and PAHs (a loss of 50% in naphthalene in the aqueous extract and, at the same time, an increase in the concentration of some contaminants in the clam’s soft tissue (especially Cu and Zn) and shells (especially Mn). Generally, lower toxicity was observed after than before filtration by C. fluminea. When exposed to biofiltered AEA, a smaller inhibition on the growth of the primary producers was observed (statistical significant in both growth rate and yield of L. minor) as well as a much lower luminescence inhibition of V. fischeri (or even luminescence stimulation of several tested concentrations) and non toxic effects were reported in D. magna. Thus, the negative ecological effects resulting from the presence of the invasive species C. fluminea can eventually be somewhat compensated by additional services provided to the ecosystem.
25
Karnieli, Arnon 1952. "Storm runoff forecasting model incorporating spatial data". Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/191138.
Testo completoAbstract (sommario):
This study is concerned with design forecasting of storm hydrographs with emphasis on runoff volume and peak discharge. The objective of the study was to develop, calibrate and test a method for forecasting storm runoff from small semi-arid watersheds using an available prediction model. In order to turn the selected prediction model into a forecasting model an objective procedure in terms of an API-type model was developed for evaluating the soil moisture deficit in the upper soil layer at the beginning of each storm. Distinction was made between the physically-based parameters and the other fitting parameters. The rainfall excess calculation was computed by solving the Green and Ampt equation for unsteady rainfall conditions using the physically-based parameters. For the physically-based parameters a geographic information system was developed in order to account for the variability in time and space of the input data and the watershed characteristics and to coregister parameters on a common basis. The fitting parameters were used to calibrate the model on one subwatershed in the Walnut Gulch Experimental Watershed while the physically-based parameters remained constant. Two objective functions were selected for the optimization procedure. These functions expressed the goodness of fit between the calculated hydrograph volume and peak discharge and the observed volume and peak discharge. Linear relationships between the effective matric potential parameter and the two objective functions obtained from the sensitivity analyses made it possible to develop a bilinear interpolation algorithm to minimize, simultaneously, the difference between the calculated and observed volume and peak discharge. The prediction mode of the model was tested both on different storm events on the same subwatershed and on another subwatershed with satisfactory results. In the prediction mode the effective matric potential parameter was allowed to vary from storm to storm, however, in the forecasting mode these values were obtained from the API model. Relatively poor results were obtained in testing the forecasting mode on another subwatershed. These errors were able to be corrected by changing the channel losses fitting parameters.
26
Hawkins, Richard H. "A Taxonomy of Small Watershed Rainfall-Runoff". Arizona-Nevada Academy of Science, 1990. http://hdl.handle.net/10150/296444.
Testo completoAbstract (sommario):
From the Proceedings of the 1990 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 21, 1990, Arizona State University, Tempe, ArizonaA study of over 11,000 event rainfall and associated direct runoff events from 100 small watersheds was done, in a search for distinct patterns of runoff response and/or association with land type. The results show unexpected variety in the geometry and scale of the rainfall -runoff response. Groupings of similar response type and magnitude were made, and the associations with vegetative cover were tested. Five separate response groups were identified as follows: 1) Inactive, characterized by no recorded responses to any rainstorm in an extended period of record; 2) Complacent, characterized by a very small part of the rainfall (ca 0.1 to 3 percent) being converted to direct runoff, often as a linear response; 3) Standard behavior, the expected "textbook" response common to agricultural lands and humid sites, and in which the runoff slope increases with increasing rainfall, and the scale of runoff far exceeds the complacent response; 4) Violent behavior, in which an abstraction threshold of 2 -6 cm clearly precedes a sudden high response; and 5) Abrupt response in which a very high portion of the rainfall is converted to event runoff without appreciable abstraction, as typified by extensively urbanized drainages. The responses and the group identifications were parameterized by a simple broken -line linear rainfall-runoff equation, and a dichotomous key based on coefficient values is proposed. Only mild associations between response type or coefficient values and the four vegetative covers (Forest, Range, Agriculture, and Urban) were found. The variety of hydrologic behavior on forested watersheds encompassed that of the other three land types.
27
Sen, Sumit Srivastava Puneet Clement Prabhakar Thangadurai. "Runoff generation in pastures of the Appalachian plateau region of North Alabama". Auburn, Ala, 2009. http://hdl.handle.net/10415/1714.
Testo completo
28
Maurer, Edwin P. "Predictability of runoff in the Mississippi River Basin /". Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10120.
Testo completo
29
Bishop, Gary D. "Uncertainty analysis of runoff estimates from runoff-depth contour maps produced by five automated procedures for the northeastern United States". PDXScholar, 1991. https://pdxscholar.library.pdx.edu/open_access_etds/4313.
Testo completoAbstract (sommario):
Maps of runoff-depth have been found to be useful tools in a variety of water resource applications. Producing such maps can be a challenging and expensive task. One of the standard methods of producing these maps is to use a manual procedure based on gaged runoff data, topographic and past runoff-depth maps, and the expert opinion of hydrologists.
This thesis examined five new automated procedures for producing runoff-depth contour maps to see if the maps produced by these procedures had similar accuracy and characteristics when compared to the manual procedure. An uncertainty analysis was used to determine the accuracy of the automated procedure maps by withholding gaged runoff data from the creation of the contour maps and then interpolating estimated runoff back to these sites from the maps produced. Subtracting gaged runoff from estimated runoff produced interpolation error values. The mean interpolation error was used to define the accuracy of each map and was then compared to a similar study by Rochelle, et al., (1989) conducted on a manual procedure map.
30
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
31
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%.
32
Macholl, Jacob A. "Identifying potential runoff contributing areas in a glaciated landscape using a GIS-based model /". Link to full text, 2009. http://epapers.uwsp.edu/thesis/2009/Macholl.pdf.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2009.Submitted in partial fulfillment of the requirements for the degree Master of Science in Natural Resources (Water Resources), College of Natural Resources. Includes bibliographical references (leaves 28-29).
33
Seibert, Jan. "Conceptual runoff models - fiction or representation of reality?" Doctoral thesis, Uppsala University, Department of Earth Sciences, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-290.
Testo completoAbstract (sommario):
Available observations are often not sufficient as a basis for decision making in water management. Conceptual runoff models are frequently used as tools for a wide range of tasks to compensate the lack of measurements, e.g., to extend runoff series, compute design floods and predict the leakage of nutrients or the effects of a climatic change. Conceptual runoff models are practical tools, especially if the reliability in their predictions can be assessed. Testing of these models is usually based solely on comparison of simulated and observed runoff, although most models also simulate other fluxes and states. Such tests do not allow thorough assessment ofmodel-prediction reliability. In this thesis, two widespread conceptual models, the HBV modeland TOPMODEL, were tested using a catalogue of methods for model validation (defined as estimation of confidence in model simulations). The worth of multi-criteria validation forevaluating model consistency was emphasised. Both models were capable to simulate runoffadequately after calibration, whereas the performance for some of the other validation tests wasless satisfactory. The impossibility to identify unique parameter values caused large uncertainties in model predictions for the HBV model. The parameter uncertainty was reducedwhen groundwater levels were included into the calibration, whereas groundwater-levelsimulations were in weak agreement with observations when the model was calibrated againstonly runoff. The agreement of TOP-MODEL simulations with spatially distributed data was weak for both groundwater levels and the distribution of saturated areas. Furthermore, validation against hydrological common sense revealed weaknesses in the TOPMODEL approach. In summary these results indicated limitations of conceptual runoff models and highlighted the need for powarful validation methods. The use of such methods enables assessment of the reliability of model predictions. It also supports the further development of models by identification of weak parts and evalution of improvements.
34
Lee, Hyo Sang. "Regionalisation of rainfall-runoff models in the UK". Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/8147.
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35
Liu, Jinliang. "Improvement in runoff parameterization for global climate modelling". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58635.pdf.
Testo completo
36
Westerlund, Camilla. "Seasonal variations of road runoff in cold climate /". Luleå, 2005. http://epubl.luth.se/1402-1757/2005/13.
Testo completo
37
Jiang, Ruiyun. "Investigation of Runoff Curve Number Initial Abstraction Ratio". Thesis, The University of Arizona, 2001. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0027_m_sip1_w.pdf&type=application/pdf.
Testo completo
38
Su, Yuming. "Storm water runoff treatment with multi-chamber pipes". Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1177524622.
Testo completo
39
Freer, James E. "Uncertainty and calibration of conceptual rainfall runoff models". Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266810.
Testo completo
40
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
41
Voytenko, Denis. "Modeling Direct Runoff Hydrographs with the Surge Function". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3398.
Testo completoAbstract (sommario):
A surge function is a mathematical function of the form f(x)=axpe-bx. We simplify the surge function by holding p constant at 1 and investigate the simplified form as a potential model to represent the full peak of a stream discharge hydrograph. The previously studied Weibull and gamma distributions are included for comparison. We develop an analysis algorithm which produces the best-fit parameters for every peak for each model function, and we process the data with a MATLAB script that uses spectral analysis to filter year-long, 15-minute, stream-discharge data sets. The filtering is necessary to locate the concave-upward inflection points used to separate the data set into its constituent, individual peaks. The Levenberg-Marquardt algorithm is used to iteratively estimate the unknown parameters for each version of the modeled peak by minimizing the sum of squares of residuals. The results allow goodness-of-fit comparisons between the three model functions, as well as a comparison of peaks at the same gage through the year of record. Application of these methods to five rivers from three distinct hydrologic regions shows that the simple surge function is a special case of the gamma distribution, which is known to be useful as a modeling function for a full-peak hydrograph. The study also confirms that the Weibull distribution produces good fits to 15-minute hydrograph data.
42
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.
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Turpin, Owen Charles. "Development and testing of a glacier runoff model". Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286866.
Testo completo
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Giuntoli, Ignazio. "An assessment of simulated runoff from global models". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7238/.
Testo completoAbstract (sommario):
This thesis assesses long-term runoff projections from global multi-model ensembles used in hydrological impact studies. Firstly, the study investigates global-scale changes in frequency of high and low flow days towards the end of the current century, quantifying the relative contribution to uncertainty from global climate (GCMs) and global impact models (GIMs). Results show increases in high flows for northern latitudes and in low flows for several hotspots worldwide. Overall, GCMs provide the largest uncertainty; but GIMs are the greatest source of uncertainty in snow-dominated regions. Secondly, the ability of a set of GIMs to reproduce observed runoff is evaluated at the regional scale, indicating that GIMs capture well trends in low, medium, and high flows, but differ from observations with respect to medium and high flows timing. Thirdly, the contribution to uncertainty from GCMs, GIMs, Representative Concentration Pathways (RCPs), and internal variability is quantified for transient runoff until 2099. Over the USA, GCMs and GIMs are responsible for the largest uncertainty. Efforts to improve runoff projections should thus focus on GCMs and GIMs. In particular, GIMs should be evaluated in the region of study, so that models reproducing unrealistic runoff can be excluded, potentially yielding greater confidence in ensemble projections.
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Abegaz, Gizachew Abebe 1956. "Prediction of sediment and runoff from Korisheleko Watershed". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191897.
Testo completoAbstract (sommario):
An event based model for estimation of sediment yield and runoff volume showed a reasonable result when compared to the measured values. MUSLE and SCS runoff models were used to predict sediment yield and runoff volume from the Korisheleko Watershed. Parameters for the models were estimated using soil loss data from test plots, soil survey data, land use data, and topographic map of the watershed. The predicted sediment yield and runoff volume were compared with the measured values. Statistical analysis including a paired comparison test and simple regression were made to validate the MUSLE and SCS runoff models. A peak flow equation for the watershed was developed applying a Unit hydrograph principle. The developed equation was based upon common rainstorm events of 1983 with an effective rainfall duration of 30-minutes. Individual components of the models could be improved with further research and data.
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Yazdi, Sara Kazemi. "Stormwater detention and infiltration devices treating road runoff". Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/14714.
Testo completoAbstract (sommario):
This thesis compares four individual projects involving innovative approaches to the problems facing stormwater management in urban areas. The first study ‘The Glasgow Sustainable Urban Drainage System (SUDS) Management Project’ satisfies the first phase of the Glasgow Surface Water Management Project. The project showed also how SUDS can contribute to the overall catchment dynamics of cities. Detailed design and management guidelines were then drafted for selected representative demonstration areas. A combination of infiltration trenches or swales with ponds or underground storage were the most likely SUDS options for the majority of the demonstration areas. Soil contamination issues were considered when selecting SUDS because heavy metals such as lead and zinc can cause environmental health problems. During the second study, 103 sites within Edinburgh were identified to assess the applicability of sustainable urban drainage systems (SUDS) being integrated into future development, regeneration and retrofitting plans. A practical SUDS Decision Support Model based on a matrix and weighting system, incorporating the Prevalence Rating Approach for SUDS Techniques (PRABT) has been developed. The aim of the third study was to assess constraints associated with the planning, design and operation of stormwater infiltration systems, the influence of aquatic plants on water quality and the overall water treatment potential. Runoff from a lightly trafficked road within The King’s Buildings campus, mixed with dog faeces was used to simulate the real life conditions. The experimental site comprising a silt trap, a below-ground detection tank and two infiltration ponds (one planted and one unplanted) was fed by road runoff. The last study examined whether multiple regression analysis and neural network models could be applied successfully for the indirect prediction of the runoff treatment performance with water quality indicator variables in an experimental storm water detention system rig. Five mature experimental storm water detention systems with different designs treating concentrated gully pot liquor were assessed in this study.
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Jacobs, Kyle Bowers. "Recovery of Antibiotic Resistance Genes From Agricultural Runoff". Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/88743.
Testo completoAbstract (sommario):
The reduced capacity of antibiotics to treat infections is one of the greatest health concerns that society faces. There is substantial evidence that links this reduced capacity with the widespread use of antibiotics in livestock production. Livestock can act as reservoirs of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria, which can pass resistance on in the livestock's manure. It is important to understand the fate of antibiotic resistance genes and resistant bacteria in the environment after land-application of manure-based amendments. The goal of this field-scale study was to identify the effects of soil amendments (inorganic fertilizer, compost, or raw manure) and crop cover (lettuce or radish) on sediment transfer, fecal indicator bacteria (FIB), and release of ARGs in runoff over six storm events. Two FIB (Escherichia coli and enterococci) and two ARGs (sulI and ermB) were quantified in runoff from each of the constructed plots throughout the growing season. FIB and ARGs were recovered from all plots, including control plots indicating a background level within the soil. Additionally, only the effects of variability among individual storms had an impact on the concentration of FIB in runoff. Vegetative cover and storm variability affected sediment release. A trend of higher sul1 and ermB in runoff from compost and raw manure-amended plots for at least 2 months after planting crops was observed. Only one of these ARGs (ermB) is associated with the class of drugs given to the dairy cows used for the manure and compost, indicating inherent carriage of some ARGs independent of the type of antibiotic administered, and such genes can persist in the environment. These results suggest that there is a risk of ARGs being carried into areas downgradient from agricultural plots that have been amended with compost or manure.MS
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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
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Godsey, Sarah. "Runoff Generation on Barro Colorado Island (BCI), Panamá". University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1059398714.
Testo completo
50
Zakharova, J., H. Pouran, John Bridgeman, A. Wheatley e M. Arif. "Understanding metal concentration and speciation in motorway runoff". Taylor & Francis Group, 2020. http://hdl.handle.net/10454/18297.
Testo completoAbstract (sommario):
YesAlthough highway runoff has historically been extensively studied, the increasing complexity of stormwater management means that there are still significant gaps regarding the reduction of soluble metals. The work reported in this paper addresses these challenges by analysing the presence and behaviour of iron, copper and zinc in runoff from junction 24 of the M1 motorway in the UK (peak traffic flow: 30,000 vehicles per hour) and comparing it with other urban sources of metals found in the same catchment (a local brook and sewage treatment works). The sampling site included an interceptor and a treatment lagoon and the event monitoring indicated a trend by which the metals did not change their concentration or particulate soluble proportion immediately, hence showing that pre- and post-storm conditions are important factors when analysing the solubility of metals and their behaviour. The data provided further evidence of the important influence of storm characteristics on metal concentrations in highway runoff, in particular the effects of an antecedent dry weather period (ADWP). In addition, this study also helped us to better understand how the release of sodium the application of de-icer for road maintenance in winter affects the availability of zinc.
The full-text of this article will be released for public view at the end of the publisher embargo on 13 Nov 2021.