ADCP's Application to Ocean Current Measurement in Davao (Sasa Wharf)

1. Where is Davao (Sasa Wharf)?

Port Scale and Throughput

Davao's Sasa Wharf represents an important part of the port infrastructure within Davao City, Philippines. It boasts a substantial scale and plays a very important role in handling large volumes of cargo. This wharf can accommodate all kinds of vessels, from a medium-sized cargo vessel up to a much larger one carrying containers. The volume of annual throughput accommodates anything from agricultural products like banana, pineapple, and other fruits Davao is noted for in exports, down to machinery, consumer goods, and construction materials being imported. Throughput has been on a gradual increase for the last couple of years due to the growing economy and expanding trade in the region.

Routes and Business

Sasa Wharf has links with various domestic and international ports. Domestically, it serves as an important link in the conveyance of goods to and from various parts of the country, helping in the distribution of products produced locally within the country. International - The firm established trade routes with countries around Asia, Oceania, and other regions. For value, business operations mainly include loading and unloading of containers and bulk cargo, storage within large areas in the warehouses near the wharf, and value-added services such as packaging, sorting, customs clearance facilitation, and support to local fishing by allowing docking facilities for fishing boats to handle fishery products.

Management and Operation of Port

In this light, the management of the Sasa Wharf is under the charge of the proper port authority office in Davao, namely for controlling berth utilization of vessels, access of vehicles and persons to wharf, coordination on general facilitation matters with Customs, Immigration and Quarantine departments. The wharf is designed with berths, warehouses, and handling equipment that are constantly repaired and improved to make handling more efficient as the demands of shipping evolve.

Facilities of the Port

Modern berths capable of taking vessels of variable dimensions, spacious warehousing facility with most modern mechanized storaging system that protects goods against all forms of damages and ensures inventory management in order, loading-unloading accessories, such as cranes, forklifts, and conveyor belts, and finally facilities offering elementary services to the vessels: refueling stations, fresh water provisioning points, workshops for the repair of vessels.

Channel and Direct Shipping

The Sasa Wharf has a well-marked channel that enables safe access and exit of ships. Depth and width are monitored regularly, with dredging done whenever necessary to accommodate larger vessels. Having direct shipping connections with most major ports in the world significantly reduces transportation time and cost, thus encouraging more international trade. The availability of direct shipping routes has made it a preferred choice among exporters and importers in the Davao region.

2. Why do we need to measure ocean currents in Davao-Sasa Wharf?

Implication on Shipping Navigation

Sasa Wharf's ocean current should be measured because there are implications of the direction of the current and the speed that would ensure proper estimation in the maneuvering of vessels while berthing and at departure, thus saving safety. In a busy port, like Sasa Wharf, with many arriving and leaving ships, information on ocean currents can prevent collision accidents with wharf structures or other vessels. It is particularly important when the weather is bad or when there are larger vessels to handle which have less mobility.

Impact on Cargo Handling Operations

The information on ocean currents is also vital for the efficient processes of cargo loading and unloading. Different current conditions can affect the actual time and stability required for these operations; for example, strong currents could call for readjustment in the positioning of ships or the use of added mooring equipment to safely protect the workers and cargo being transferred. With correct current measurements, port operators could schedule these operations more favorably with a view to reducing delays in improving general productivity.

The Role in the Planning of Port Infrastructure

Knowledge of ocean currents becomes quite critical for the long-term development and expansion of the port. These currents, through hydrodynamic forces, have an impact on the durability and stability of structures comprised in the wharf, the berths, and the piers. It is required for an engineer who is designing and constructing new infrastructure that must be able to bear the continuous action of the currents. It also helps in pinpointing the most feasible locations for future expansions and improvements in order to minimize the detriments of the water flow.

Acoustic Doppler Current Profiler (ADCP) is an advanced and more convenient means of measuring ocean currents compared to other conventional methods. It can rapidly and precisely provide detailed current information at different depths, offering real-time data indispensable for the efficient operation and future development of Davao's Sasa Wharf.

3. How do ADCPs using the principle of Doppler work?

ADCPs work on the principle of Doppler. They emit acoustic signals into the water. The acoustic waves interact with the suspended particles or other scattering objects in water that are moving along with the ocean current. When the waves are reflected back to the ADCP meter, the frequency of the reflected waves changes due to the Doppler effect.

With the exact measurement of this frequency shift, the ADCP current meter can estimate the ocean current speed at several levels along its measurement range.

ADCP in Port Ocean Current Measurement

Shipborne ADCP

Shipborne ADCPs are mounted on ships that operate in and around Sasa Wharf. The ship travels in waters around the port, while the ADCP flow meter constantly sends acoustic signals in several directions. It can sample the current data in more than one point over the track of the vessel. That can produce an overall picture of the distribution of ocean currents in relation to various wharf areas. The outcome offers an instantaneous situation over the relatively big area that the ship traverses.

Fixed ADCP

Fixed ADCPs are usually deployed from fixed locations within the port, for instance, on the seabed near important infrastructure such as the wharf's berths, or at strategic points in the waterway. They do not move and will be continuously measuring the ocean current condition at that very point over an extended period of time. This gives consistent and long-term data that is of value in understanding the regular patterns of the currents, and thus assessing their impact on port facilities and operations at those fixed positions.

4. What's needed for high-quality measurement of Davao (Sasa Wharf) currents?

Material Reliability

The equipment to be used for current measurement at Sasa Wharf has to be made of reliable materials. These challenges should be withstood without degradation of the performance of a measuring device, considering that marine conditions are harsh, with such factors as saltwater corrosion, changing water pressures at different levels of depth, and the constant action of waves. One of the best materials for the casing of ADCPs is titanium alloy. It offers high strength to thus withstand the mechanical forces in the marine environment, and it is made of outstanding corrosion resistance that will make it survive for a long time in seawater.

Size, Weight, and Power Consumption

The equipment should also be of smaller size, light in weight, and with low power consumption. Smaller in size, it allows for easy installation at different areas of the wharf, whether on ships or at fixed locations. Lightweight promotes handling and deployment easily, while low power consumption means that equipment can work without requiring heavy or frequently changed batteries and other extreme power supplies. This is necessary in order to provide continuous long-term monitoring at the port.

Cost-Effectiveness

Cost-effectiveness will enable large-scale measurement across the wharf. Equipment should be reasonably affordable to enable multiple units to go out and acquire comprehensive current data from within the port area. This would help to get a more accurate and comprehensive understanding of the general patterns of ocean currents around Sasa Wharf.

5. How to Choose the right equipment for current measurement?

Usage Purpose

• Shipborne ADCP: In a case where there is the intention of having a mobile measurement while the ship does run-around in circles around the wharfs and harbors, and for any who seek rapid grasp of an overall notion concerning current status on each substructure in this port, for example, shipborne ADCP could be highly desirable. In its usages, during normal vessels traveling over broad areas can be covered.
• Bottom-mounted ADCP: For the continuous monitoring of the ocean current on a specific fixed location in the port, such as near major facilities or at places of interest where one needs good observation of current effects against structures, bottom-mounted ADCP is more appropriate. Stable and consistent data for that specific position over long periods is one of the great advantages of such a device.
• Buoy-mounted ADCP: When the installation of fixed equipment on the seabed or on other structures is inconvenient, buoy-mounted ADCP can be deployed. The buoy-mounted ADCP measures the ocean current of the upper layers of the water body and sends it wirelessly to create flexibility in data gathering.

Based on Frequency Difference

• The general rule of thumb is to use 600 kHz ADCP for water depths up to 70 meters at Sasa Wharf, because it will measure ocean current characteristics quite accurately within this pretty shallow depth.
• In contrast, 300 kHz is more suitable when the water depth is around 110 m and can effectively capture current details for that particular depth.
• ADCP 75 kHz: It should be selected for deeper water areas, with a water depth up to 1000 meters, because it can penetrate deeper into the water and give reliable current information.

There are several well-known ADCP brands in the market, including Teledyne RDI, Nortek, and Sontek. However, there is a Chinese ADCP brand worth recommending: China Sonar PandaADCP. It is made of all-titanium alloy material with an excellent cost-to-performance ratio. You can know more about it on its official website: https://china-sonar.com.

Here is a table with some well known ADCP instrument brands and models.