Amazon River (Brazil) Discharge Measurements with RiverSurveyor ADP

Amazon River Discharge Data
using a RiverSurveyor ADP
(Over 4,000,000 ft³/s !!)

March 28, 2001 - Brazilian hydrologists from the National Agency of Energy and Electric (ANEEL), ITAIPU Binacional, and SonTek, Inc., put the SonTek RiverSurveyor Acoustic Doppler Profiler (ADP) to the test on the Amazon River (Rio Amazonas) near Manaus, Amazonia, Brasil. The RiverSurveyor's performance during the measurements was impressive, and the discharge measurement results were exceptional.

Background: Just getting to the measurement site required the hydrologists to fly from the cities of Brasilia and Foz Do Iguassu to Manaus, Amazonia to board the 30-m vessel Capt. Darios and begin a four-hour journey up the Amazon River to the Manacapara discharge gauging station operated by ANEEL.

After departing the Port of Manaus, small Indian villages along the way provided the only glimpses of civilization along this remote section of the Amazon River, home to the largest rain forest in the world. Upon arriving at the measurement site, hydrologists quickly made preparations to begin measuring discharge on the largest river in the world.

The Setup: A 0.5-MHz RiverSurveyor ADP was mounted on a rigid aluminum frame and positioned vertically (looking down) near mid-ship on the starboard side. This location provided the most stability for the ADP and reduced any likelihood of magnetic interference of the internal compass from the ship's engines.

Immediately before discharge measurements were to be taken by the RiverSurveyor, hydrologists from ANEEL inspected the Manacapara gauging station to record the water lever and to confirm the proper operation of the gauges. This was done to ensure an accurate comparison of the discharge measured by the RiverSurveyor to the "rated (predicted) discharge"⁽¹⁾ at the discharge station operated by ANEEL.

The 0.5-MHz RiverSurveyor ADP was then connected to the computer, and off they went. Programming the ADP for these measurements was similar to any other RiverSurveyor deployment, which only require three entries -- maximum water depth, transducer depth, salinity. The RiverSurveyor software automatically programmed the depth cell size, blanking distance, and the number of depth cells.

The Results: With thunderstorms quickly approaching, there was only enough time for two measurements. As expected, the results from the measurements were definitive! The two measurements were within one percent of the discharge predicted by the "stage-discharge" rating curve developed by ANEEL. Had the RiverSurveyor ever been to the Amazon River before? NO! Did it get it right the first time? YES! Check out one of the measurement runs below -- over 4,000,000 ft³/s!!!

(1) Rated (predicted) discharge is determined from a calibration curve (stage-vs-discharge) developed by ANEEL at the Manacapara discharge gauging station on the Amazon River.

• RiverSurveyor ADP