This thesis deals with rainfall and water runoff regime in the catchment area of river Klabava. The aim of this thesis is to find changes in the rainfall-runoff regime during the period of observations (1950-2014) and if so, were these changes caused by climate changes or human activities. The research part includes description of rainfall-runoff process and Klabava catchment area description. In the applied part there is an analysis of precipitation - runoff regime for long-term time series of average and minimal annual, monthly and seasonal discharges and annual, monthly and seasonal precipitations using single and double mass curves and statistical tests testing absolute homogeneity, relative homogeneity and trend (by Mann-Whitney-Pettit, Alexandersson, Mann-Kendall tests). The tests were performed by freely available software AnClim designed for these purposes. Mann-Kendall test was performed by MULTMK/PARTMK available as a MS Excel macro for free. Plus, there is basic discussion of floods in Klabava river basin and flood seasonality. The homogeneity tests haven't found many changes at all, most of the detected changes concern the minimal runoff time series. The precipitation annual amount was detected with a raising trend, while the runoff time series seem to have no trend at all. Achieved...

by Wan Yuk-ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 146-152). / Abstracts in English and Chinese. / List of Tables --- p.i / List of Figures --- p.iii / List of Plates --- p.v / Chapter CHAPTER I --- INTRODUCTION / Chapter 1.1 --- Scope of the Problem --- p.1 / Chapter 1.2 --- Importance of the Urban Sediments on the Environment --- p.8 / Chapter 1.3 --- Hydrological and Sedimentological Problems Related to Urbanization -a Storm Event Basis --- p.13 / Chapter 1.4 --- Studies in Sub-tropical Humid Areas --- p.17 / Chapter 1.5 --- Objectives of this Research --- p.18 / Chapter CHAPTER II --- CHARACTERISTICS OF URBAN SEDIMENTS / Chapter 2.1 --- Sediments Transportation Pattern of Storm Events --- p.19 / Chapter 2.2 --- Particle Size Parameter --- p.29 / Chapter 2.3 --- Volatile and Chemical Parameters of Total Sediment Loading --- p.33 / Chapter 2.4 --- Problems Arisen from the Review of Previous Studies and Directions --- p.36 / Chapter CHAPTER III --- METHODOLOGY / Chapter 3.1 --- Experimental Design --- p.37 / Chapter 3.1.1 --- Catchment Approach --- p.38 / Chapter 3.1.2 --- Storm base Approach --- p.39 / Chapter 3.2 --- Study Area --- p.41 / Chapter 3.2.1 --- Rainfall Pattern --- p.41 / Chapter 3.3 --- Nature of the Study Areas --- p.44 / Chapter 3.3.1 --- Location --- p.45 / Chapter 3.3.2 --- Relief and Geology --- p.47 / Chapter 3.3.3 --- Landuse Pattern --- p.49 / Chapter 3.3.4 --- Climatic Condition --- p.57 / Chapter 3.3.5 --- Streamflow Measurement --- p.59 / Chapter 3.4 --- Suspended Sediment Concentration --- p.61 / Chapter 3.4.1 --- Sample Collection --- p.61 / Chapter 3.4.2 --- Laboratory Procedures --- p.62 / Chapter 3.4.3 --- Instantaneous Sediment Concentration --- p.63 / Chapter 3.5 --- Volatile and Mineral Solids --- p.63 / Chapter 3.6 --- Particle Size Measurement --- p.65 / Chapter CHAPTER IV --- TRANSPORTATION PATTERN OF STORM SEDIMENTS IN URBAN CATCHMENTS / Chapter 4.1 --- Introduction --- p.66 / Chapter 4.2 --- Suspended Sediment Transport Patterns During Storm Events --- p.70 / Chapter 4.3 --- The Relationship Between Discharge and Instantaneous Sediment Concentration --- p.81 / Chapter 4.4 --- Additional Factors Affecting Instantaneous Sediment Concentrations During Storm Events --- p.87 / Chapter 4.4.1 --- University Campus --- p.88 / Chapter 4.4.2 --- Fo Tan --- p.91 / Chapter 4.5 --- Discussion --- p.93 / Chapter CHAPTER V --- SEDIMENT CHARACTERISTICS / Chapter 5.1 --- Introduction --- p.97 / Chapter 5.2 --- Characterization of Sediments --- p.98 / Chapter 5.3 --- Variations in Sediment Size --- p.101 / Chapter 5.3.1 --- Between-Storm Variations in Particle Size --- p.103 / Chapter 5.3.1.1 --- Size Distribution Curves --- p.103 / Chapter 5.3.1.2 --- Median Particle Size --- p.107 / Chapter 5.3.2 --- Within-Storm Variations in Particle Size --- p.108 / Chapter 5.3.3 --- Factors Affecting the Between Storm Variations in Sediment Particle Size --- p.120 / Chapter 5.4 --- Variations in the Sediment Volatile Content --- p.123 / Chapter 5.4.1 --- Differences in Sediment Volatile Content Between the Two Catchments --- p.123 / Chapter 5.4.2 --- Variations in Volatile Content Between and Within Storms --- p.124 / Chapter 5.4.3 --- Timing of the Volatile Content Peaks --- p.128 / Chapter 5.4.4 --- Factors Affecting the Volatile Content --- p.131 / Chapter 5.4.5 --- Some General Observations on Sediment Volatile Content --- p.133 / Chapter 5.5 --- Summary and Discussion --- p.133 / Chapter CHAPTER VI --- CONCLUSION / Chapter 6.1 --- Summary of Findings --- p.137 / Chapter 6.2 --- Implications of the Research Findings --- p.141 / Chapter 6.3 --- Limitations of this Study and Suggestions for Future Work --- p.143

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.

This study used a geographic information system (GIS) and an empirical pollutant load model to estimate average annual pollutant loads contained in storm water charges from the City of Carrollton, Texas. The Geographic Resource Analyses Support System (GRASS) was used to create a number of spatial data layers as input variables to a model that estimates loads in Kilograms/Hectare/Year, and Kilogram/Basin/Year. Average annual pollutant loads for twelve pollutants were derived from average annual rainfall/runoff volumes, coupled with Local Dallas/Fort Worth Metroplex storm water Event Mean Concentrations.

No description available.

The Umzimvubu catchment on the eastern coastal escarpment of South Africa is sensitive to anthropogenic influences,with commercial and subsistence agriculture, irrigation, domestic and rural settlements and forestry compete for water use. An adequate supply of water to the region is seen as imperative in the light of the recent establishment of forest cultivation. In order to provide a sound assessment of the impacts of afforestation on the catchment, the subsurface hydrological processes of hillslopes on the Molteno sedimentary formations of the region must be clearly understood. Since the runoff hydrograph is, to a large degree, dependent on the subsurface processes, a number of models that simulate small catchment runoff have been developed. However, recent successful application of tracer techniques to hydrological modelling has shown that the subsurface processes are still not fully understood (Schultz, 1999), and whether or not the subsurface processes are modelled adequately is most often not verified, since there is a lack of relevant data. It is, therefore imperative that the subsurface component of these small catchment runoff models be improved. This can be achieved by first observing detailed subsurface water dynamics and assessing these against the catchment runoff response. In this dissertation, results from a detailed experiment that was initiated in a 1.5 km2 catchment in the northern East Cape Province are shown. Nests of automated tensiometers, groundwater level recorders and weather stations have been placed at critical points around the catchment, and these , together with soil hydraulic and physical characteristics are used to define and identify the dominant hillslope processes. Two crump weirs record runoff from these hillslopes. The results of this subsurface study highlight the dynamics of surface and subsurface water in the hillslope transects. It is evident that the subsurface processes are strongly influenced by the -bedrock topography as well as the soil characteristics, such as macropore flow and deep percolation. Using the monitored data and 2-D vadose zone modelling, the dominant hillslope processes have been defined and are used to aid in the selection of critical parameters to be used in estimating the catchment runoff. Results show that a clear understanding of the subsurface dynamics can lead to a realistic estimation of catchment scale runoff response. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

No description available.

Thesis (M.E.S.)--Evergreen State College, 2003. / Title from title screen viewed (4/15/2009). Includes bibliographical references (leaves 56-58).

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.E.S.)--Evergreen State College, 2007. / "June, 2007." Title from title screen (viewed 4/8/2010). Includes bibliographical references (p. 52-54).