This study presents an unsteady-state hydraulic model analysis of hurricane storm surge and rainfall-runoff interactions in the Clear Creek Watershed, a basin draining into Galveston Bay and vulnerable to flooding from both intense local rainfalls and storm surge. Storm surge and rainfall-runoff have historically been modeled separately, and thus the linkage and interactions between the two during a hurricane are not completely understood. This study simulates the two processes simultaneously by using storm surge stage hydrographs as boundary conditions in the Hydrologic Engineering Center’s – River Analysis System (HEC-RAS) hydraulic model. Storm surge hydrographs for a severe hurricane were generated in the Advanced Circulation Model for Oceanic, Coastal, and Estuarine Waters (ADCIRC) model to predict the flooding that could be caused by a worst-case scenario. Using this scenario, zones have been identified to represent areas in the Clear Creek Watershed vulnerable to flooding from storm surge, rainfall, or both.

This thesis concerns general improvements to rainfall runoff models and focuses on two particular aspects, namely flood-wave routing in the main channel and consistent parameterisation of the rainfall-runoff process under different degrees of discretization of the catchment. The primary goal is to: 1) describe a general methodology for parameterisation of a rainfall runoff model so that the parameters are consistent across catchments modelled at different discretization scales and 2) develop an improved channel routing technique which takes proper account of the effects of all characteristics of wave motions in the channels. The first of these concerns methods for removing the inconsistency of parameterisation that results from different catchment discretizations in rainfall-runoff models. A stochastic Tokunaga network is developed for dealing with the scaling inconsistence. The problem of network embedding is also discussed. The second is a relatively simple method for the solution of the full dynamic wave equations for one-dimensional channel flow, which accurately simulates the effects of shocks. / PhD Doctorate

Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1983. / Includes bibliographical references (leaves 90-92).

Thesis (M.Sc. (Natural Resources Management))--Mahidol University, 2006.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 104-106). Also available via the Internet.

Thesis (M.S.) University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 24, 2007) Vita. Includes bibliographical references.

Computer modeling is the powerful tool for simulating nature’s behavior; however, still more efforts are need for reaching perfect simulation with computer models (especially in the hydrological field of study). In this Master’s thesis, the accuracy of the HEC-HMS computer model for long term rainfall-runoff simulation was evaluated across Sweden. Five different catchments from north to south of Sweden were selected and then simulation have done for 34 years of available data. Simulation was conducted using daily, monthly and yearly time scale resolutions. Results from the north to the south of Sweden were completely different. Simulated runoff and observed runoff in northern catchments followed the same pattern over different time scales but in the southern part of Sweden the results had different patterns in space and time. The best results with HEC-HMS were found in the northern catchments with steep main river slopes. In the southern catchments the model could not predict runoff in any realistic manner at any time and space scale. In total the HEC-HMS model cannot simulate the rainfall runoff for long periods of simulation across Sweden. This is especially true in southern parts of the country dominate with low elevation catchments. However, with regards to its ability for event-based simulation HEC-HMS could be a suitable tool to simulate flood event discharges that are needed for road or other hydraulic structures designs. But, this would require significant amounts of calibration and model development.

More than a billion dollars are spent annually on stream restoration in the United States (Bernhardt et al., 2005), but the science remains immature. A promising technique for estimating a single or range of design discharges is the generalization of a parsimonious conceptual continuous simulation model. In this study the Probability Distributed Model (PDM), was generalized for the Maryland and Virginia Piedmont. Two hundred and sixty years of daily average flow data from fifteen watersheds were used to calibrate PDM. Because the application of the study is to stream restoration, the model was calibrated to discharges greater than two times baseflow and less than flows with a return period of ten years. The hydrologic calibration parameters were related to watershed characteristics through regression analysis, and these equations were used to calculate regional model parameters based on watershed characteristics for a single "ungaged" independent evaluation watershed in the region. Simulated flow was compared to observed flow; the model simulated discharges of lower return periods moderately well (e.g., within 13% of observed for a flow with a five year return period). These results indicate this technique may be useful for stream restoration and wetland design. / Master of Science

This dissertation reports on the methods and results of a three-phased investigation to estimate the annual volume of ephemeral-channel-focused groundwater recharge attributable to urbanization (urban-enhanced groundwater recharge) in the Sierra Vista subwatershed of southeastern Arizona, USA. Results were used to assess a prior estimate. The first research phase focused on establishment of a study area, installation of a distributed network of runoff gages, gaging for stage, and transforming 2008 stage data into time series of volumetric discharge, using the continuous slope-area method. Stage data were collected for water years 2008 - 2011. The second research phase used 2008 distributed runoff data with NWS DOPPLER RADAR data to optimize a rainfall-runoff computational model, with the aim of identifying optimal site-specific distributed hydraulic conductivity values and model-predicted infiltration. The third research phase used the period-of-record runoff stage data to identify study-area ephemeral flow characteristics and to estimate channel-bed infiltration of flow events. Design-storm modeling was used to identify study-area predevelopment ephemeral flow characteristics, given the same storm event. The difference between infiltration volumes calculated for the two cases was attributed to urbanization. Estimated evapotranspiration was abstracted and the final result was equated with study-area-scale urban-enhanced groundwater recharge. These results were scaled up to the Sierra Vista subwatershed: the urban-enhanced contribution to groundwater recharge is estimated to range between 3270 and 3635 cubic decameters (between 2650 and 2945 acre-feet) per year for the period of study. Evapotranspirational losses were developed from estimates made elsewhere in the subwatershed. This, and other sources of uncertainty in the estimates, are discussed and quantified if possible.

The aim of The Diploma Thesis was to compile a conceptual rainfall-runoff model, that would be eligible to model discharge in conditions of climate changes. After thorough verifications of possible variants, user program Runoff Prophet that is eligible to simulate discharge in closing profile of any river basin was compiled within this paper. Runoff Prophet is deterministic lumped model with monthly computation time step and from the hydrologic phenomena it takes soil moisture, evapotranspiration, groundwater flow and the watercourse flow into account. Its calibration is based on the differential evolution principle with Nash–Sutcliffe model efficiency coefficient as the calibration criterion. Developed software was tested on Vír I. catchment basin and the results of this probe were evaluated from viewpoints of air temperature, precipitation and discharge characteristics in the Dalečín measurement river cross section in distant future according to A1B SRES climate scenario, implemented in LARS-WG weather generator.