From 2015 to 2017, EnerTek conducted a study of the Marañon river for the Lorena Hydroelectric Power Plant (650 MW). Located in Bagua in the department of Amazonas, the study included topobathymetric surveys along 12 km of the Marañon, and flow measurements to develop a rating curve take at two locations. The conditions at the site were challenging, and included high flow, turbulent water and high sediment levels.
The topobathymetry study, which covered an area of more than 275ha, was completed using an acoustic doppler echo sounder (ADCP), the latest technology for high precision hydrological studies. Continuous hydrological monitoring was carried out at four hydrometric stations (designed and installed by EnerTek), which included staff gauges, water level sensors and barometric sensors. The sensors continuously measured water level and air pressure every 30 minutes, which was then calibrated with daily photos of the water level at the staff gauges.
The flow measurements were taken at transects with widths from 80m to 150m and water speeds up to 6m/s. The sites did not have road access, so a cable and pulley system was designed to allow the ADCP to traverse the river. Water quality and sediment sampling was also included in the study. Results were presented in a series of reports delivered after each measurement campaign and a final report at the end of the study.