The revitalization plan was made for Kubňů Černá pond in Třeboň basin, Czech Republic. The detailed field survey concentrated on evaluation of ponds current state and the functioning of the drain and the spillway protective dick. Based on field survey, the revitalization was divided into three steps that dealed with retention capacity improvement, facilities renovation, dam renovation and ecosystem stability improvement. The revitalization program would be supported by Ministry of the Environment of the Czech Republic due to high financial demands.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A multiplicaÃÃo da quantidade de pequenos reservatÃrios no semiÃrido nordestino provoca um impacto considerÃvel na disponibilidade hÃdrica das mÃdias e grandes bacias hidrogrÃficas, tornando-se assim, um impeditivo no bom gerenciamento deste recurso. Por outro lado, a pequena aÃudagem tem um importante papel com a retenÃÃo de sedimentos oriundos da erosÃo da bacia hidrogrÃfica, fazendo com que haja a minimizaÃÃo dos impactos causados com o acumulo de sedimento nos reservatÃrios estratÃgicos, causadora da conseqÃente reduÃÃo na disponibilidade de Ãgua. Desta forma, buscou-se analisar o assoreamento do aÃude BoqueirÃo, situado na Bacia Experimental de Aiuaba â BEA, atravÃs de estudos de batimetria, avaliaÃÃo hidrossedimentolÃgica na bacia hidrogrÃfica e a caracterizaÃÃo do material depositado e sua distribuiÃÃo no reservatÃrio. O assoreamento do reservatÃrio foi calculado pela diferenÃa entre as topobatimetrias de 2003 e 2009, e atravÃs de regressÃo linear, avaliou-se o assoreamento desde 1934, Ãpoca de sua construÃÃo. Cinco trincheiras foram feitas ao longo do talude da bacia hidrÃulica do reservatÃrio, permitindo avaliar o seu assoreamento aÃude atravÃs de parÃmetros do solo. A eficiÃncia de retenÃÃo do reservatÃrio foi determinada atravÃs da razÃo entre o assoreamento estimado no perÃodo de 1934 a 2009 e a produÃÃo de sedimentos obtida pÃlo modelo hidrossedimentolÃgico Hidrosed â 1. O assoreamento volumÃtrico foi calculado em 3.613 t para o perÃodo de 76 anos. Obteve-se valor de 6,5 % de teor de matÃria orgÃnica como sendo o limiar entre o material de assoreamento e o material original do terreno. Salienta-se ainda que apenas 7 % do material de assoreamento que foi produzido pela bacia hidrogrÃfica ficaram retidos em seu exutÃrio. Portanto, conclui-se que o assoreamento volumÃtrico anual do reservatÃrio à da ordem de 0,056 %, causando uma reduÃÃo na capacidade de acumulaÃÃo do reservatÃrio de 4,5 % desde a Ãpoca de sua construÃÃo atà os dias atuais. Evidencia-se, ainda, o teor de matÃria orgÃnica como um bom indicador do assoreamento do reservatÃrio: o volume assoreado, considerando-se como tal o solo com teor de matÃria orgÃnica maior que 6,5%, foi apenas 15% superior ao obtido atravÃs de batimetria. A eficiÃncia de retenÃÃo baixa pode ser explicada pela reduzida razÃo entre o volume do reservatÃrio e sua bacia hidrogrÃfica. Isto sugere que grande parte do sedimento que à produzido na bacia à exportado alÃm do exutÃrio atravÃs de eventos fluviomÃtricos extremos. / The multiplication of the number of small reservoirs in the semiarid northeastern causes a considerable impact on water availability of medium and large river basins, thus becoming a hindrance to good management of this resource. Moreover, the small damming has an important role in the retention of sediments from the erosion of the basin, minimizing the impacts to the accumulation of sediment in strategic reservoirs, and the consequent reduction in water availability. We have analyzed the sedimentation of the BoqueirÃo reservoir, located in the Experimental Basin of Aiuaba - BEA, through studies of bathymetry, hydrosedimentological assessment in the watershed and characterization of the deposited material and its distribution in the reservoir. The silting of the reservoir was calculated as the difference between bathymetry of 2003 and 2009 and, by regression, we estimated the sedimentation since 1934, the time of its construction. Five trenches were made along the slope of the hydraulic basin, allowing to assess the silting of the reservoir through soil parameters. Finally, the retention efficiency of the reservoir was determined by the ratio of sedimentation estimated for the period 1934-2009 and sediment yield obtained by the hydrosedimentological model Hidrosed - 1. The sedimentation mass was calculated as 3613 t for the period of 76 years. We obtained a value of 6.5% organic matter content as the threshold between the material of original material and the silting material. According to our analysis, only 7% of the sediment yield of basin are retained in the outlet reservoir. Therefore, it is concluded that the annual volume of reservoir sedimentation is the order of 0.056%, with a reduction in the accumulation capacity of the reservoir of 4.5% since the time of its construction. It also shows the content of organic matter as a good indicator of siltation of the reservoir, as the silted assessed using the organic matter threshold (6.5%) was only 15% higher than that obtained by bathymetry. The low retention efficiency might be explained by the low volume-catchment area ratio, suggesting that much of the sediment that is produced in the basin is exported through its outlet during the extreme runoff events.

This diploma thesis deals with the reconstruction of small reservoir in collaboration with the company VZD Invest s. r. o. The first part aims at the basic description of the thesis subject – the small reservoir. Characteristics of small reservoir and calculations are processed in the second part. The third part is focused on the description of the current conditions. The main part consist of characteristics calculations of the small reservoir and proposal of the necessary reconstruction for future technical function. In conclusion, safety assessment of the proposed measures are evaluated.

This diploma thesis, called „Reconstruction of the small water reservoir Hradisko in the cadastral area of Radslavice“, focuses on the complex process of a reconstruction of the small water reservoir Hradisko. This work follows up on the bachelor’s thesis, in which the current state of the Hradisko reservoir was described in detail. Based on the survey of the dam and the flood using a GPS device, detailed project documentation was prepared. Within the solution for the reconstruction of Hradisko reservoir, a repair of the dam and the increase of the crown of the dam is proposed, new functional objects are dimensioned, the bottom is cleared of mud, including modifications in the flood, and other necessary steps for proper functioning of the crumbling no longer compliant reservoir are described. Functional objects are processed for two variants of the solution. The first option consists of the design of a bottom outlet and a safety spillway, and the second alternative involves the design of a combined functional block. In the end, the total costs of both options are quantified and compared on the basis of an indicative item budget.

This thesis deals with the design of small reservoirs at Vyškov na Moravě. Projected reservoirs’ dams are earth-fill and homogenous and each one is equipped with the bottom water outlet and the emergency spillway. The first reservoir, located on the tributary of the Drnůvka river, has the fountain type emergency spillway and the feed pipe bottom water outlet. The reservoir of the Merchanice river, situated at the Vyškov airport, is equipped with the lateral emergency spillway and the feed pipe bottom water outlet. The third design is the reconstruction of the Marchanka reservoir projecting the dam raise. For this small reservoir two variants of functional installations were elaborated.

Doctor of Philosophy / Department of Biological & Agricultural Engineering / James K. Koelliker / Small reservoirs catch and store water for long periods and they decrease streamflow and increase ground-water recharge. A field monitoring program provided the measured water depth for four years in several reservoirs in the Republican River Basin where there are concerns about their aggregate effects in the basin. The daily water budget operation for one reservoir was developed. Daily seepage rates were estimated by using precipitation, inflow and evaporation which was assumed equal to grass reference evapotranspiration (ET0), that average 120 to 150 cm/yr, along with the measured stage-storage and stage-surface area relationships. Two computer simulation modules, written in FORTRAN 95, were developed to estimate 1) overflow and gross seepage and 2) potential for ground-water recharge underneath the reservoir. Required daily input data are precipitation, ET0, and inflow from the watershed area. Required reservoir site characteristics include stage-storage and stage-surface area relationships, a standard seepage rate (S0) at 14 different levels in the reservoir, soil-water and plant-growth characteristics and a monthly crop-residue factor. The gross seepage module calculates water depth that determines daily overflow, the water-surface area for evaporation and the head of water on the 14 levels to cause seepage losses. If a level is not inundated, seepage is zero. If a level is inundated less than 0.3-m, S0 is used. When the water head (hL) on a level exceeds 0.3 m, the seepage rate (SL) is increased by, SL = S0 * (hL/0.3)0.25. This relationship was chosen after testing several exponent values between 0 and 1. The modules were calibrated on one reservoir and verified on two others in northwestern Kansas. Results showed runoff from the watersheds averaged about 1.2 to 1.6 cm/yr from the average annual precipitation of 46 to 62 cm. The three reservoirs reduced streamflow at the reservoir site by 74 to 97%, but 90 to 95% of the retained runoff was calculated to contribute to ground-water recharge. Several sensitivity analyses for model inputs were done. Results showed that, the ratio of the average annual inflow volume from the watershed area to the reservoir storage volume was the most sensitive input variable tested.