Pilotage invests in dynamic draft on the Amazon River

Tests to validate an 11.90-meter draft have already begun in the region that undergoes the world’s largest sediment discharge

The implementation of a dynamic draft system is underway in the North Bar of the Amazon River, under an ordinance signed between the Cooperative for PZ-1 Pilots’ Support and Logistics (Unipilot) and the Command of the 4th Naval District.

The integrated data collection and processing system calculates how much a ship can increase its underwater volume without risk of running aground, considering data such as tide intervals and so on. The information is fundamental for increasing vessel loading, since the North Bar is a shallow muddy stretch along 23 nautical miles (42.6 kilometers) at the mouth of the Amazon River, limiting the draft of all ships in the Amazon.

The region is extremely complex, since the so-called Arco Lamoso (“muddy arc”) has a large sediment discharge in the river, which has one of the world’s highest flows. Added to this is the action of another three components: the astronomical tide caused by gravitational effects of the Earth-Moon-Sun system; the meteorological tide influenced by strong winds, and the river level as a result of the rainfall pattern.

The first of the system’s three meteo-oceanographic buoys was anchored in the North Bar and underwent structural adjustments to be less prone to entrapments of fishing nets, for example. Furthermore, the watertightness of its sensors, which provide data of currents, tide level and water density, was reinforced. Buoy surveillance operates without records of vandalism, thanks to a partnership with local fishermen.

The project relies on the technical backing of Argonáutica, a company created by the University of São Paulo (USP), which developed the dynamic draft in the Port of Santos, and on the Cohesive Sediment Dynamics Laboratory of the Federal University of Rio de Janeiro (UFRJ). All collected data are shared via satellite with the Brazilian Navy, responsible for authorizing the maximum draft in the region.

At the moment, two trials have been performed with an 11.75m draft. Another two crossings with 11.80m; four with 11.85m; and four more with 11.90m are programmed to validate this draft – all utilizing a tide of 3.10m or more. The stretch requires extremely accurate navigation so that the vessel does not touch the riverbed. This is why it must be carried out at low speed, constantly monitoring the under-keel clearance. A representative from the Maritime Authority (from the Northern Center of Hydrography and Navigation) and a PSC naval inspector (Port State Control) accompany the trials onboard.

“It was a good result, the ship sailed clear”, says pilot Adonis dos Santos, president of Unipilot, who did the second 11.75m crossing.

To proceed with the trials, the Maritime Authority prefers to wait for the results of a marigraph at Céu Point, Grande Canal do Curuá, 70 miles from the North Bar. The technical study at the site began in 2017 to implement the dynamic draft. The marigraphs of the Brazilian Navy and the pilot station were destroyed by uprooted tree trunks during a tidal bore (pororoca). The Unipilot apparatus was expected to be reinstalled on August 31.

Another key pilotage effort for the success of the project is regular depth soundings of the region’s rivers to supplement the official soundings. The work has been carried out for more than ten years and is crucial to the navigation of heavier ships because, in the Amazon, sandbanks move constantly under water, altering the navigation channels. These investments in bathymetry and in tide studies have contributed to the Navy increasing the draft from 11.50m in 2017 to 11.90m at the trial stage (more than a USD million gain in cargo per ship). The pilot station believes it’s possible to reach 12.50m with the system’s advance.

“We have this series of trials to consolidate the increase in the authorized 11.90m maximum draft. It will be a benchmark in potentializing agribusiness exports through the North Arc and the productivity of Itacoatiara (Amazonas-AM), Santarém (ParáPA) and Santana (Amapá-AP) terminals, promoting expansion to the hinterland (area of commercial influence) of the Amazon ports. The investment is funded by the pilot station, in partnership with the Maritime Authority”, highlights the Unipilot president.

Pilot Ricardo Falcão, president of Brazilian Pilotage, who also works in the East Amazon Basin, recalls that all input of resources is only feasible because, in the 1960s, the Brazilian Navy made pilotage a private activity:

“In addition to withstanding the high cost of the profession’s operation, with special motorboats and a 24-hour standby operations center, all pilot stations invest heavily in combining safe navigation with efficiency. The result of the past Navy decision is visible in the quality of the service and productivity it generates for the country.

Soybean and corn products, for example, plus bauxite, containers, petroleum and by-products, are more and more often transported along the Amazonian rivers. Agribusiness freight in the Midwest arrive by barges on the Madeira River to Itacoatiara (AM) and on Tapajós River to Santarém (PA). In the port terminals, cargo is transferred to ships sailing down the Amazon River.

According to the data from Brazil’s agency for waterway transportation (Antaq), in the first six months of 2022 the North Arc terminals, including those in Maranhão, for the first time surpassed the ports in the other regions in handling soybean and corn products, with 51% national participation (41.5 million tons).

Around 1,300 vessels a year pass through the Amazon region, almost half carrying agribusiness freight. Top producer Mato Grosso is responsible for 72 million tons of grain, estimated to reach 120 million tons by 2030, and ten years later 60 million tons to be exported through the North Arc, as estimated by the Mato Grosso Pro-Logistics Movement. The draft progression is key to the distribution of the increasing production.

Pilot Station Opens Up Routes For Exports

The ZP-1 pilots operate in the world’s largest pilotage zone, in an area covering 1,416 nautical miles (2,622km) of navigation and maneuvers in the Amazonian rivers, ranging from the mouth of the Amazon River and the city of Itacoatiara (AM), passing through three states, Amapá, Pará and Amazonas. This requires very intensive use of pilots, raising the cost of internal travel for the service and millions in investments to ensure efficient and safe ship handling.

In addition to routine checks of river beds and tide analysis, the pilot station then began to study alternative routes to those that once limited navigation, as in the case of Mazagão Channel, 13 miles from Fazendinha (AP), towards Itacoatiara (AM). The pilots’ expertise was also valuable to overcome operational limits of very tight bends in the Jari and Trombetas Rivers, with up to 50% larger vessels.

On Trombetas River, however, after the addition of night beaconing, the pilot station made a huge effort to adjust the signage and train maneuvers at night. Another port that will be able to operate round the clock with night beacons and adapted tugs is Santana (AP), thanks to the pilots’ participation in simulations in the University of São Paulo Numerical Offshore Tank (TPN-USP). The work also confirmed the possible entrance of New Panamax ships to Amapá, with two extra holds for cargo and capacity of up to 100,000 tons. Crossing the North Bar with heavier loaded ships is the next bottleneck to overcome.

PILOTS' EXPERTISE HELPED OVERCOME LIMITS IN THE TROMBETAS RIVER