Scientific Annals of the Danube Delta Institute (May 2019)
“Checking the Pulse” of Sf. Gheorghe’s Arm Meanders from the Danube Delta Biosphere Reserve
Abstract
The meanders of the Sf. Gheorghe arm of the Danube Delta Biosphere Reserve in Romania were cut through a hydrotechnical intervention in the late 80s and beginning of 90s. This river regulation was nominated in the investment plan of the National Water Council and was part of the framework scheme for the Dobrogea hydrographic area. This part of the Danube river had been rectified for 15 km altogether for the following meanders: Murighiol, Dunavat, Dranov and Ivancea which shortened the route with 32 Km. The benefit of these changes is clear: improve the water transportation by shortening the route, less time spent on transportation ergo, less fuel consumption. The downside is represented by clogging of the lateral connectivity, silting up the mouth of the river and of the adjacent water complexes. The Danube Delta would not have been a delta without water. By accelerating the discharge also, the sedimentation processes are increased. The water complexes are dependent on the direct communication with the main river through the still existing channels. If these channels would silt up and close the connection between the water complex and the main river, then the eutrophication process will increase to a point of no return but through another hydrotechnical works, then is a matter of time until the meanders turn into oxbow lakes that will dry up. And little by little the areas between the main arms of the Danube Delta would dry up since there is no water running towards them. At this moment, the mouth of the channels that link the main water course and the adjacent water complexes are almost closed, the meanders silted up and their water body considerably reduced by connected islets along their course with shallow depths. All these negative aspects could and can be avoided if the authorities would invest in upgrading these hydrotechnical works done almost 30 years ago by implementing the feasible approach for each segment of the cut. In essence, this study will provide accurate topo-bathymetrical data upon which GIS analyses will elaborate the actual state of these meanders.
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