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characteristics of the region - Sudets, agricultural region, clean. Begining 1997 a new geografic situation. On the road between Jesenik Mountains and big cities. This region has many problems (unemployment, bad conditions for tourism) but the damm not only wrong. It is a good oportunity for development...

No description available.

No description available.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23476号 / 工博第4888号 / 新制||工||1764(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 渦岡 良介, 教授 三村 衛, 教授 肥後 陽介 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

A groundwater model of a 126.2-acre ranch in Cambria, California was expanded upon to analyze the effects of artificial recharge and a subsurface barrier. The ranch lies within the 48mi2 Santa Rosa Creek Watershed along the Central Coast of California. The mainly agricultural watershed outfalls to the Pacific Ocean to its west. Creek Lands Conservation, a non-profit that aims to conserve and restore habitat along the Central Coast, plans to identify projects to restore stream flow during dry seasons in the creek that runs through the Santa Rosa Creek Watershed and to increase artificial groundwater recharge. This study focuses on two of those projects. One project is an existing recharge basin and the other is a subsurface barrier. The objective of this numerical model is to improve upon an existing model by using a longer duration of data to calibrate the model, calibrating the model to hydraulic properties of soil samples that were obtained from the site at various depths, refining elevations of layers through integration of new borehole exploration data, and adding updated and new data such as mountain front recharge and pumping rates. The modeling program used was GMS which allows calculation and determination of heads and flow directions. Within the model, there are three separate layers based on hydrogeological characterization from previous studies. There is an upper unconfined zone, a confining clay layer, and a confined zone. A package within GMS (Groundwater Modeling System) called PEST (i.e., Parameter ESTimation) was used to calibrate the model to known water surface elevations throughout the site. Data such as elevations, head boundaries, stream flow, pumping rates, recharge, evapotranspiration, well locations, and hydraulic properties of the subsurface was processed and incorporated into the overall model in GMS. Recharge rates from the basin were estimated to be 0.1 m/day roughly starting in February and ending in May for each year. The model showed that the confining layer slows down the flow of water from the recharge basin, but it does eventually percolate into the underlying groundwater aquifer before reaching Santa Rosa Creek after a time period of 5 years. The proposed subsurface barrier does reduce travel times of groundwater by roughly a year and helps percolation of water into the confined layer. With the subsurface barrier it was seen that the water held within the confined aquifer increased on average 5,200 m3 each year.

Levees are a significant part of the United States flood protection infrastructure. It is estimated that over 100,000 miles of levees exist in the United States. Most of these levees were designed many years ago to protect farmland and rural areas. As growth continues in the United States, many of these levees are now protecting homes and other important structures. The American Society of Civil Engineers gave the levees in the United States a grade of D- in 2009. To bring flood protection up to modern standards there requires adequate methods of evaluating levees with respect to seepage, erosion, piping and slope instability. Transient seepage analyses provide an effective method of evaluating seepage through levees and its potentially destabilizing effects. Floods against levees usually last for days or weeks. In response to a flood, pore pressures within the levee will change from negative (suction) to positive as the phreatic surface progresses through the levee. These changes can be calculated by finite element transient seepage analyses. In order for the transient seepage analysis to be valid, appropriate soil properties and initial conditions must be used. The research investigation described here provides simple and practical methods for estimating the initial conditions and soil properties required for transient seepage analyses, and illustrates their use through a number of examples. / Ph. D.

Yes / Solutions for dam-break flow mainly developed for rectangular channels are not applicable to prediction of the propagation of the dam-break wave in frictional triangular channels. This study presents an approximate solution considering the frictional effect on the dam-break flow in a dry horizontal triangular channel. Wave tip velocity is solved by an implicit formula for the product of time and resistance coefficients. All other hydraulic properties in the wave tip region can be expressed as explicit functions of wave tip velocity. Meanwhile, laboratory experiments have been performed for obtaining water surface profiles of dam-break flow from which the position and velocity of the wave tip front have been derived. Results show that retardation of the wave front position is more significant with the increases in both resistance and time. The proposed analytical solution shows satisfactory agreement with measurements, and clarifies how the behavior of the dam-break wave tip is affected by channel geometry.

Water resources for Bluff Lake in Mississippi are managed to achieve objectives related to waterfowl, waterbirds, fish, anglers, and Paddlefish (Polyodon spathula). Annually, the reservoir undergoes a nine-stage seasonal drawdown and re-inundation to improve waterfowl habitat. In addition, weekly discharges are released from the water control structure to encourage Paddlefish spawning and migration each spring. However, additional discharges throughout the year may provide additional passage opportunities. In this study, multiple discharge states were evaluated to identify optimal water releases during each drawdown period given reservoir objectives. First, I developed a hydrodynamic model to predict daily changes in lake volume. Second, I defined functional relationships between water surface elevation and management objectives. A structured decision-making framework was then applied to determine the optimum additional discharge strategy. This approach allowed trade-offs between management objectives to be evaluated and optimal water releases to be identified for this multiuse reservoir.

The Oakohay Creek watershed in Smith County, Mississippi, had been proposed as a site for the development of a reservoir. The site has been assessed for hydrogeologic suitability. There were three components to the site assessment. The first component involved examining the hydrologic characteristics of the drainage basin. Discharge and stage were monitored at eight sites, providing data for the development of hydrographs. The second component of the study was based on studying the site?s geology. The geology was studied through field reconnaissance, surface mapping, interpretation of geophysical well log data, and development of cross sections. The third component of the study involved the assessment of water quality within the basin. Samples were taken for analysis by the Mississippi State Chemical Laboratory. The results of the site assessment indicate that the proposed site is not suitable based on the hydrology, geology, and water quality of the study area.