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Volume XVII |

Arch dam failure preliminary analysis using HEC-RAS and HEC-GEO RAS modeling. Case study Someșul Rece 1 reservoir

Abstract: This paper presents a preliminary analysis/simulation of the Someşul Rece 1 dam breaking scenario, from the homonym hydrographic basin, located in the north-eastern part of the Apuseni Mountains, at a 0.1 % probability tributary flow rate calculation. The study of the floodplain areas, that occur after the failure of the Someşul Rece 1 dam, was achieved with the help of 1D hydrological modelling. This type of modelling is one of the most complex (Cameron et al., 2006), involving both, the definition of a model with temporal evolution of the dam rupture, and the simulation of a unsteady flow stream in the downstream sector. For the dam analysed area and the downstream sector, several scenarios and modelling of hydrological systems was achieved, with the help of HEC-RAS 5.0.3 software, developed by the Hydrologic Engineering Center (U.S. Army Corps of Engineers).This free software is the most widely used worldwide in the domain, particularly by the official agencies, having a continuous development, given by the involvement of specialists. The software simplifies the problem of hydrodynamic modelling, due to the limitation to a 1D model. Because the flood obviously has a spatial character, GIS software (ESRI ArcGis with the HEC-GeoRAS extension) were used in determining and defining the hydrographic elements (channel, talweg, banks etc.) and, also, in the representation of the results. Maps of the flood-prone areas have been developed, maps which indicated the magnitude of the estimated accidental flood downstream. The results of the simulation were also used to determine the anticipation time.

Volume XVII |

Playing with water – An introduction to experimental hydrology

Abstract: Water is the most important resource for the humankind, thus understanding hydrological processes could be con-sidered a vital task. Therefore, the main aims of this papers are to assess: (i) the current status of hydrologic field ex-periments; (ii) the techniques and the stages of the field hydrologic experiments at the microscale/plot-scale. Microscale hydrological studies are important both socially and economically as they emphasize the role of key factors (e.g. slope) in the utilization of water resources, the identification of critical hydrological thresholds for mobilizing, the propagation of soil particles in water flows and also the time it takes for pesticides, nutrients, and heavy metals to be mobilized. The key to conducting a successful hydrological microscale experiment lies in performing repeated attempts in the field. From an economic point of view, expedition (temporary) hydrologic field experiments are beneficial, as they shorten the working period and reduce the financial costs of the data acquisition process. One of the challenges of experimental hydrology is the manipulation of “upscaling” or the statistical approach taken towards gathering and processing data.

Volume XVII |

Estimation of drinking water supply and its future trends in Varanasi city, India

Abstract: The current study shows the estimation of drinking water supply, future trends and related issues in Varanasi City, India. Varanasi (from 25013’N to 25024’N latitudes and from 820 54’E to 830 04’E longitude) is one of the most important and historic city located almost in the Middle Ganga valley in the northern plain of India. For the convenience of civic administration, the city is presently divided into 90 wards and for the purpose of extending adequate and safe water supply facilities to the entire area, the city has been divided presently into 16 water supply zones of which 5 zones lie in the trans-Varuna area and the remaining 11 zones in the cis-Varuna area. The present work is based on the secondary sources of data which are obtained from Water Supply Department (Jal Sansthan), Nagar Nigam (Municipal Corporation) of Varanasi. In the first phase of the study, data pertaining to ward wise generation of water supply is collected from Water Supply Department, NNV (Nagar Nigam Varanasi). Informal focused group discussion, PRA (Participatory Action Research), and observation technique were applied to get the first hand information about the water supply scenario in the city. In the second phase of the study, Arc GIS 10.1 software was used to create maps for estimation of water supply management. The population growth in Varanasi from 2011 to 2041 is estimated to have a growth of 21% in 30 years at a rate of 2.25 % per year. This growth rate is considered in the model from 2011 to 2041 to predict the water demand in the city. The data was collected from various municipalities as per the office records. It is estimated that the amount of drinking water requirement forecasted for 2021, 2031 and 2041 is 0.49, 0.76 and 1.17 Billion liters per day respectively in Varanasi City. These data show that with an increase in population, the water demand is also increasing decade after decade. Increasing population growth rate, decreasing surface water resources, overexploitation of groundwater, deterioration of ground water quality and poor sewage treatment are the major water supply related issues in Varanasi city, India.

Volume XVII |

Indicators for evaluating the role of green infrastructures in sustainable urban development in Romania

Abstract: Urban green infrastructures are now considered key elements in improving residents’ quality of life and creating an appropriate framework for the development of sustainable cities. One of the most efficient method to evaluate the state and performance of urban green infrastructure is using different types of indicators. The indicators for evaluating the benefits, ecosystem services and the role of green infrastructures for the process of sustainable development represent important tools for decision and policy makers. Indicators provide information that can be easily interpreted by decision and policy makers and they facilitate the process of planning, monitoring and evaluation of green infrastructure in urban areas. The focus of our study is to establish which indicators are used for underlining the structural and functional diversity of urban green infrastructures. This paper aims to highlight the indicators and indices being used in Romanian urban areas for measuring their sustainability that include green infrastructures, in the wider understanding of the concept. Throughout the paper, different examples of indicators and indices are provided, emphasizing that by using the proper set of indicators and indices, city authorities can tag a sustainable development label for certain areas. However, an unbiased assessment using some sets of indicators and indices are not always providing unbiased or realistic outcomes.

Volume XVII |

Using GIS methods to analyze spatial characteristics of urban transportation system in Craiova city

Abstract: In a world of technology, where the increasing urbanization tries to cope between sprawl and the need to actively manage a sustainable land and resources use, transportation remains among the main challenges for physically active cities like Craiova. The city is the major growth pole located in South-West Oltenia, which connects most of the settlements in the region (both rural or urban) economically and socially. Thus, the transportation system represents the key element in the relation between time and place in this metropolitan area in a continuous development process. While the city expands, the transportation network, inherited from the past, suffers a slower transformation, despite the increasing demand for mobility coming from both passengers and freights. The spatial analysis of new residential areas emerged in the continuous process of urban expansion indicate an additional pressure on the existing road infrastructure and which intensifies especially during peak hours on the access routes to the city and city center. Starting from the analysis of the spatial structure and distribution of the pre-existent rural structure, the present study tries to emphasize the need for an innovative and integrated infrastructure that should connect at its best space, services and people in terms of speed, capacity and cost efficiency. First, using the GIS mapping methods, the authors present the spatial distribution of the transport infrastructure that is correlated with population density and land use, also analyzing the areas with high density of jobs and elements of the urban landscape that may generate attractivity. A special attention is paid to the urban form – street pattern relation, exemplified by case studies in problematic intersections of Craiova city. All these factors are important in order to establish the present capacity of the urban transportation system during peak hours, and what are the main deficiency of the transport system: traffic jams, insufficient parking places, need of new connections in public transportation. The results of the research may be used to improve passenger transport inside the city of Craiova and may also suggest some solutions that mitigate for the introduction of new concepts like car sharing, electric public transportation, hybrid vehicles or new alterna-tives for peoples’ movement.