The study area viewed in Google Earth 

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... altitude at the point of change for the slope angle. Density of the reference points is another important parameter influencing the accuracy of a digital terrain model, also. The higher the density of the points, the greater the precision and accuracy of ground surface – all these aspect are very important features in modelling of the flood waves propagation of. [7] The most common method for obtaining digital terrain models is to interpolate contours and height points from topographic maps at different scales. The accuracy with which is described the morphology and altimetry accuracy of digital terrain model is influenced by the chosen interpolation method (TIN - vector representations of geographic data and are constructed by triangulating a set of vertices/ points or TopoToRaster – that takes into account multiple inputs: contours, points listed, hydrographic network - rivers, lakes and land surface characteristics) and the density topography data (contours, points listed). TIN and TopoToRaster methods produce similar results where we have high amount of data related to land height along the riverbed, otherwise it is recommended to use a combined procedure of the two methods of interpolation. [7] Topographic data sets can be obtained by photogrammetric processing. In Romania, following the 2008 Payments and Intervention in Agriculture Agency project, of obtaining orthorectified aerial imagery for the entire national territory, it was generated a national digital terrain model by photogrammetric method. APIA Specifications for obtaining orthorectified images by, and thus to achieve digital terrain model were to scale 1: 5000, thus imposing a vertical accuracy of 1 m. In recent years, the use of LIDAR sensors and data from it exceeded the research, and proved to be suitable for fast generation of digital terrain models. Before undertaking specific analyzes based on LIDAR data, their consistency need to be checked. Considering that LiDAR files contain most cases millions of points, the result of a flight LIDAR results in multiple LAS files, this way of reading the information contained LIDAR files is very useful to determine their composition and spatial coverage. To obtain information related to riverbeds (bathymetry data) it is required to be executed by surveying cross sections or by using sonar. Minor beds should be treated separately for the construction of a digital terrain model and continuously connected with precision digital terrain model obtained for the floodplain. [7] MIKE 11 is a professional engineering software package for simulation of one- dimensional flows in estuaries, rivers, irrigation systems, channels and other water bodies. It was developed by DHI Water • Environment • Health, Denmark. The Hydrodynamic Module (HD), which is the core component of the model, contains an implicit finite-difference 6-point Abbott-Ionescu scheme for solving the Saint- Venant’s equations. The formulation can be applied to branched and looped networks and flood plains. HD module provides fully dynamic solution to the complete nonlinear 1-D Saint Venant equations, diffusive wave approximation and kinematic wave approximation, Muskingum method and Muskingum-Cunge method for simplified channel routing. It can automatically adapt to subcritical flow and supercritical flow. It has ability to simulate standard hydraulic structures such as weirs, culverts, bridges, pumps, energy loss and sluice gates. The model has been designed to perform detailed modelling of rivers, including special treatment of floodplains, road overtopping, culverts, gate openings and weirs. MIKE 11 is capable of using kinematic, diffusive or fully dynamic, vertically integrated mass and momentum equations. Boundary types include Q-h relation, water level, discharge, wind field, dam break, and resistance factor. The water level boundary must be applied to either the upstream or downstream boundary condition in the model. The discharge boundary can be applied to either the upstream or downstream boundary condition, and can also be applied to the side tributary flow (lateral inflow). The lateral inflow is used to depict runoff. The Q-h relation boundary can only be applied to the downstream boundary. MIKE 11 is a modelling package for the simulation of surface runoff, flow, sediment transport, and water quality in rivers, channels, estuaries, and floodplains. MIKE 11 has been used in hundreds of application around the world. Its main application areas are flood analysis and alleviation design, real-time flood forecasting, dam break analysis, optimisation of reservoir and canal gate/structure operations, ecological and water quality assessments in rivers and wetlands, sediment transport and river morphology studies, salinity intrusion in rivers and estuaries [8]. The area chosen for the simulation is Lac Creek in the Corne ş ti village, situated in the Corne ş ti commune, Timis County, Romania. The study area has an area of 5x5 km (2500 ha) (Figure 1). Topographic and photogrammetric measurements serve to determine the precise three- dimensional position of the objects necessary for the successful implementation of flood risk maps. Methods and technologies currently used in GAUSS srl company for the production, storage and processing of topographic information are: establisment of Control Network Stations; surveys; digital photogrammetry aerial/ satellite; aerial LIDAR Scanning; determination of groundwater (detection passive/ active); bathymetry surveys; GIS storage, integration, processing and representation of data processing. In terms of information management, cross sections were stored, in the first instance, as 2D shape. Subsequently, based on the digital terrain model, these lines were converted to 3D shapes using the command Features to 3D from 3D Analyst extension of ESRI ArcMap software. Profiles generated aggregate length is over 20 km. ArcMap layout profiles shown in Figure 3. To define the hydrographic network Stereo 70 cartographic projection system it was chosen. Raster images, digital terrain model and ortofotograme resolution of 50 cm were imported. Imported data imports could make use of the actual real coordinates; the only manual data entry was the limits of the area of interest. Also, you could import the shapefile type files which are cross-sections of rivers and shaft. Unfortunately, they could not retrieve this information directly in the corresponding editors (network and cross section). Import data was done manually, via. csv format files. Results obtained from simulation are shown in Figure 5. The simulation results were visualized using Mike View module. Topography plays an important role in the distribution of water resources in the natural environment. Vertical precision and accuracy of digital terrain model representation influences flooding delimitation necessary for proper preparation of risk maps required by EU Directives. Quality of hydrodynamic modelling and spatial representation of the results depends on the quality and quantity of inputs used. In order to draw up and update risk maps for a particular river basin, a comparative analysis between different digital terrain models of various precision altimetry should be done, obtained by classical methods of tracing and spatial interpolation, photogrammetric processing, or LiDAR surveys (by the model calibration process) to see which ones produce results more akin to the reality. For this it is necessary that, during a flood or immediately thereafter, to survey immediately the affected area, to be used as support in the calibration of hydrodynamic models for the propagation of flood waves. This paper can be possible thanks to project: Development of knowledge centres for life-long learning by involving of specialists and decision makers in flood risk management using advanced hydroinformatic tools, AGREEMENT n 0 LLP-LdV-ToI-2011-RO-002/2011-1-RO1-LEO05-5329. This project has been funded with support from the European Commission. This publication [communication] reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained ...