Quality of municipal water is sustained by addition of disinfectant, generally chlorine, to the water distribution network. Because of health problems, chlorine concentration in the network is limited between maximum and minimum limits. Cancerogenic disinfectant by-products start to occur at high concentrations so it is desired to have minimum amount of chlorine without violating the limit. In addition to the health issues, minimum injection amount is favorable concerning cost. Hence, an optimization model is necessary which covers all of these considerations. However, there are uncertain factors as chlorine is reactive and decays both over time and space. Thus, probabilistic approach is necessary to obtain reliable and realistic results from the model. In this study, a linear programming model is developed for the chance constrained optimization of the water distribution network. The objective is to obtain minimum amount of injection mass subjected to maintaining more uniformly distributed chlorine concentrations within the limits while considering the randomness of chlorine concentration by probability distributions. Network hydraulics and chlorine concentration computations are done by the network simulation software, EPANET.

Coastal regions are very important because they provide a lot of resources and benefits for all the humankind. Coastal defense structures protect coastal regions from wave attacks. However, the cost of construction such coastal defense structures are very high and need big investments. Hence, to reach the optimum design and minimize the risk of failure has vital importance during the design stage of these structures. Model studies are the most effective tool in optimizing the design of these structures. Rubble mound coastal defense structures were constructed with assembly of different sizes of armor stones and front slopes. Rubble mound coastal defense structures were designed by Van der Meer

In practice, baffle blocks and sills are commonly being used to stabilize the location of a hydraulic jump and shorten the length of a stilling basin. On the other hand, gravels, corrugations and rectangular prismatic roughnesses which cover the entire length of the basin or placed in a staggered manner may be an alternative. The objective of this study is to determine the effects of these roughness elements on the characteristics of hydraulic jumps such as conjugate depth, jump length and energy dissipation using experimental data collected from the previous studies. The investigations show that the roughness elements have positive effects on the characteristics of hydraulic jumps. The tailwater depth reduction compared to classical jump is 2-10%. The length of the jump is reduced about by 30-50% by prismatic roughness elements, 40% by corrugations, and 30% by gravels. The roughness elements induce 3-15% more energy dissipation than that of classical jump. Therefore, these types of bed roughness elements should be considered as an effective alternative of accessory devices such as baffle blocks and sills.

&Ccedil / amlidere Dam supplies significant portion of the potable water demand of the City of Ankara. Consequently, it is very important that the pipelines extending over 60 km between the dam and the treatment plant at Ivedik operate continuously. At present, two composite parallel lines are in operation and construction of a third line is considered for the future. It is the aim of this study to investigate the water hammer problems to be expected under various scenarios and also suggest the safe operation conditions for the system. Water hammer analyses of the pipeline are carried out by computer software named HAMMER. This software employs the Method of Characteristics (MoC) which is a widely used mathematical procedure in solving the non-linear differential equations caused by unsteady flow. Within this theses work, existing tunnels, prestressed concrete and steel pipes, third steel pipeline which is planned to be constructed in the future and existing, and future-planned valves are modeled and calibration of the model is implemented. A plenty of scenarios and valve closure principles are constituted in order to specify steady-state conditions and additional water hammer pressures generated by several excitations through the pipeline. Results of these scenarios are compared with previous works conducted on the pipeline system and the most unfavorable ones among those are determined. Then, appropriate closure durations are identified and suggested for pipe fracture safety valves and the flow control valves at Ivedik in order not to cause excessive pressures in the system.

Foundations of river bridges need to be protected with respect to excessive scouring. Degree of protection depends on the severity of scouring action around bridge piers and abutments. A case study is carried out to design appropriate protective measures for sequential viaducts located on Ankara-Pozant highway in Turkey. A number of analyses are conducted to obtain water surface profiles throughout the study reach. Local scour depths at piers and abutments of the viaducts are then obtained. The design process for countermeasures is performed concerning hydraulic, hydrologic, constructional, and economical requirements. To this end, riprap, partially grouted riprap, and articulated concrete blocks are studied in these view points. A criterion based on a selection index, which is defined by the National Cooperative Highway Research Program in the USA, is applied in this study. Implementation of partially grouted ripraps at infrastructural elements is found to be an appropriate solution.

A risk assessment model (MAcRisk) have been developed to forecast the probability and the risk of maritime accidents on Bosphorus. Accident archives of Undersecretariat Maritime Affairs Search and Rescue Department, weather conditions data of Turkish State Meteorological Service and bathymetry and current maps of Office of Navigation, Hydrography and Oceanography have been used to prepare the model input and to forecast the accident probability. Accident data has been compiled according to stated sub-regions on Bosphorus and event type of accidents such as collision, grounding, capsizing, fire and other. All data that could be obtained are used to clarify the relationship on accident reasons. An artificial neural network model has been developed to forecast the maritime accidents in Bosphorus.

Turkey is a developing country and its energy demand is increasing due to its growing population and industry. As a result, to fulfill this growing energy demand, Turkey is currently developing its unused hydropower potential, especially through small hydroelectric power plants (SHPPs). Estimation of annual electricity generation of a small hydropower plant strongly depends on streamflow data. In Turkey, there are a limited number of streamgaging stations so the estimation of streamflow at a potential SHPP location requires transferring streamflow time series from a reference streamgaging station to the ungaged basin. In order to determine daily streamflow time series for ungaged catchments, typically the nearest streamgaging station is chosen as the reference streamgaging station. However the distance between a reference streamgaging station and an ungaged catchment may not always be the most appropriate reference streamgaging station selection criterion. Archfield and Vogel (2010) proposed a new method called the Map Correlation Method (MCM) to select a reference streamgaging station to donate its observations to an ungaged catchment. MCM aims to identify the most correlated streamgaging station with the ungaged catchment. This new method is used at the Western Blacksea Basin in Turkey to select the best among possible reference streamgaging stations. The method proved to be promising / the most correlated streamgaging station for approximately one third of the study streamgaging stations are identified correctly by the MCM.

Intakes are inlet structures where fluid is accelerated to a certain flow velocity to provide required amount of water into a hydraulic system. Intake size and geometry affects the formation of flow patterns, which can be influential for hydraulic performance of the whole system. An experimental study is conducted by measuring velocity field in the hydraulic model of the head pond of a hydropower plant to investigate vortex formation. Vortex strength based on potential flow theory is calculated from the measured velocity field. It was shown that vortex strength increases with the submergence Froude number. The free surface flow in the head pond is simulated using Flow-3D software. Vortex strength calculations are repeated using the computational velocity distributions and compared to experimentally obtained values. Similar computations were carried on with some idealized pond geometries such as rectangular and circular.

All life depends upon water. For man, however, water can supply the power necessary to relieve him from the drudgeries of life and give the time and means to enrich his existence beyond the bounds set by the mere need to survive. Large scale hydropower makes a significant contribution to the total generated power of the developed world. The means of harnessing water power for large flows and heads above three metres are efficient and well established. There remains however, the fact that many people, especially in developing countries live adjacent to water courses and tidal estuaries where heads of 2 metres or less exist but are not exploited. The reasons for this are often that practical machines do not exist or are insufficiently well developed to be used. Much effort has been made in recent years to develop equipment suitable for small, low-head sites in remote places. The writer has worked on three such devices in both the laboratory and on site - these are the Salford Transverse Oscillator, the AUR Water Engine and the Underwater Motor. This thesis describes these machines in detail together with other contemporary devices. The initial chapter contains an assessment of machines used in the past to exploit low head sites. There is little doubt that some of these older machines, suitably brought up to date in design and materials, would be more suited to the needs of developing peoples than many of the esoteric devices described in later chapters. The thesis is concerned mainly with the need to provide a means of generating power rather than the assessment or suitability of a site for power generation. The writer draws on experience gained in the laboratory, and as a Mechanical Engineering Consultant for small installations in the United Kingdom and overseas.

Appraisal and design of small-scale hydro power plants requires a knowledge of hydraulics, hydrology, civil, mechanical, and electrical engineering, and basic economics. Further, small hydro is site specific in nature and marginal from an economic view point. Methods of appraisal and design are required therefore that will keep engineering fees to a minimum and yet still achieve a reliable evaluation of scheme potential and economics. In this context it should be appreciated that small hydro is not large hydro scaled down, and that small hydro needs its own experts (Ref. 1). This thesis considers techniques for appraisal of small hydropower schemes, the selection and specification of scheme components, their costing and economic evaluation. These appraisal techniques are subsequently applied to regional assessment of small-scale hydro-electric potential in the U. K, and to the development and application of a new type of ultra low-head hydropower generator called the Salford Transverse oscillator (STO). Although this work is predominately concerned with assessment of scheme potential in the U.K., it also draws on experience gained by the writer during short visits to India and Nepal, and during a six month design appraisal for rehabilitation of mini-hydro schemes in Sri Lanka (Ref. 2).