HYDROLOGICAL AND HYDRAULIC MODELING OF RIVER CRNA FOR EVALUATING RIVER BASIN RESTORATION MEASURES

<p>The degradation of the rivers and river basins caused by natural and/or anthropogenic factors can be prevented or significantly reduced by taking restoration measures. To define the restoration measures, it is necessary to perform a hydrological analysis of the river basin as well as a hydraulic analysis of the watercourse in the river basin.</p> <p>In this research, the hydrological-hydraulic analysis is carried out for the river Crna, for a characteristic section from the estuary of the river Crna in the river Vardar to the bridge on the E75 highway, at the Stobi archaeological site. This section is of great importance for the Republic of Macedonia because apart from the archaeological site of Stobi, which is a national institution in the field of culture, there are also the railway bridge on the "Skopje-Thessaloniki" railway and the bridges on the regional road R1102 and the highway E75, which are buildings of the first category.</p> <p>During the hydrological analysis, different methods are used, due to insufficient and discontinuous data. To determine the basic hydrological parameters, measured annual maximum flows (from 1961 to 1996) are used, and by using the databases of modern GIS, the physical-geographical characteristics of the river basin, height representation, geological, hydrogeological and pedological characteristics as well as land use are determined. By applying the HEC-RAS software package, a one-dimensional hydraulic model was created for the simulation of unsteady flow in the riverbed. With the hydraulic modeling, the hydraulic consequences are defined (flood surfaces, active erosion zones and sediment filling zones), and the most critical points are determined. The obtained results of the hydraulic analysis are analyzed, and measures are proposed in order to reduce the consequences of a flood wave.</p>