Evaluation methods of reducing bathymetric surveys to the water level instantaneous water for monitoring siltation: case study of the hydroelectric power plant reservoir Mauá

The Brazilian power industry is structured to ensure the supply of electricity to the entire nation, since the generation is done mostly through hydroelectric plants where the reservoir plays a key part in the generation process.The silting of reservoirs can directly impact in the operation and maintenance of hydroelectric plants, reducing the capacity storage and useful life. The monitoring and evaluation of the reservoir silted volume it's an important tool for follow the process and too provide the necessary information to support decision form to avoid interruption in the power generation process, as well as environmental damage.In this work it were tested three different ways to carry out the reduction in the instant water level in surveys conducted with a echo sounder for reservoirs monitoring: using the RTK observations done during the reservoir surveying, the measurements made on the right bank of the reservoir with the RTK fixed in one point, and readings in a limnimetric scale (water level gauging station).Through calculations of total vertical uncertainty and statistical test of the two averages, it was observed that the latter two techniques showed similar results and its application is feasible in study area.

Keywords:
Reservoirs siltation; bathymetric survey; reduction of bathymetric surveys and total vertical uncertainties