ADCP's Application to Ocean Current Measurement in Balabac Port

1. Where is Balabac Port?

Balabac Port is located in the Balabac municipality of the province of Palawan in the Philippines.

Port Scale and Throughput

It is very significant in the local and regional maritime trade. It does not pretend to possess the colossal throughputs characterizing some of the world's major ports; it represents, rather, an important connecting node in the carriage of goods that include fishery products, agricultural produce stemming from areas around the ports, and various commodities used by local communities. Its flow consists of vessels operating between small fishing boats and medium-sized cargo ships supporting economic activities around the region.

Routes and Business

It is connected with several domestic routes, which facilitate trade and exchanges with other ports within the Philippines. For example, there are regular shipments to and from major cities on the main island of Luzon and other important economic centers in the Visayas and Mindanao regions. Besides transportation of cargo, it provides services to the fishing industry also and acts as a mother port for fishing boats operating in the adjacent rich fishing grounds.

Port Management and Operation

Relevant local port authorities govern and oversee the running of such ports, ensuring it runs effectively. This covers routine maintenance tasks regarding berthing facilities, vessels' traffic control, handling concerns at the facility, regulating vessel traffic, and supervision of the cargo loading and unloading processes. In addition, they are to enhance port security and liaison activities with other agencies responsible in addressing emergency cases and, if necessary, safety operations concerning vessels and personnel around the port area.

Facilities at the Port

The port has several berths that can handle different vessel types. Quay walls ensure the stable docking positions for ships. Besides, there are storage areas onshore for the temporary storage of cargo in case it needs to be transported further inland or loaded onto outbound vessels. In addition, there are facilities for fueling ships and other ancillary services, including a fresh water supply.

Channel and Direct Navigation

The port has a well-defined channel through which ships can come in and go out without any danger. This channel is kept regularly to ensure the depth is enough for the vessels, especially considering the tide variation in the area. Appropriate navigational aids like buoys and lighthouses help the mariners navigate directly into the port and out from the port, keeping in the right course and avoiding potential hazards in the waters surrounding the port area.

2. Why should we measure the ocean currents in the Balabac port?

The data from accurate measurement of ocean currents in Balabac is of great importance in the port operation and management of the said place. It aids in optimizing vessel berthing and mooring operations. In knowing the direction and speed of the ocean currents, port operators can allocate the berthing positions and define the appropriate mooring arrangements of various vessels to avoid any collision and ensure the safety of the ships while at dock.

It is also very useful for the planning of ship arrivals and departures. Knowledge of ocean currents can provide the best scheduling times, enabling the ships to enter and leave at the most opportune moments, which could enhance efficiency in the general performance of the port and minimize queues of vessels waiting for entrance.

Knowledge of ocean currents also helps the fishing industry dependent on a port by helping fishermen know where to get higher concentrations of fish. Currents can bring in nutrients and affect where marine life is distributed; therefore, having accurate information on currents can enhance productivity in fishing.

Furthermore, the present data provides useful information on the hydrodynamic forces acting on port structures in terms of infrastructure maintenance as well as future expansion plans; it helps in designing more durable and stable facilities and also in predicting any possible impacts of changing current patterns on the existing infrastructure.

Generally, the Acoustic Doppler Current Profiler (ADCP) has been considered a more advanced and handier means of measuring ocean currents compared to the earlier ones. It can provide in real time and in detail information about the current profile over a certain depth range, which allows monitoring of the ocean currents in the port area more precisely and effectively.

3. How do Doppler Principle ADCPs work?

The principle behind ADCPs is the Doppler principle. They emit acoustic signals into the water column. Where these acoustic waves encounter moving particles in the water, like suspended sediment or small organisms, the frequency of the reflected waves shifts because of the Doppler effect. From the frequency shift of the reflected signals, the velocity of the moving particles and hence the velocity of the ocean current can be calculated.

ADCP in Port Ocean Current Measurement

Shipborne ADCP

Shipborne ADCPs are mounted on ships. In the process of the movement, the shipborne ADCPs keep sending acoustic pulses backward and to the side, while it measures current velocities at various depths right below the track of the ship. The data is to be used in mapping the current field in the area of the port. This is useful for getting a general overview of the current patterns over a fairly large area since the ship can cover different parts of the port during its operations.

Fixed ADCP

Fixed ADCPs are mounted in fixed positions at specific locations in the port, such as on the seabed or on fixed structures like piers. They constantly measure the ocean currents from that particular point in time. This provides long-term and consistent data on current conditions at key locations within the port, which is highly useful for understanding the regular current variations and for providing reference data for port operations and research.

4. What is necessary for high-quality measurement of currents in the Balabac port?

For high-quality measurement of ocean currents in Balabac port, several factors concerning equipment are important. First, the material reliability of the equipment is crucial. It should be able to stand the harsh marine environment: corrosion by seawater, high pressures at different depths, and impacts from floating debris.

The second advantage is that these units are small in size and lightweight. This therefore makes the installation and operating of the equipment quite easy, especially when vessels or fixed structures in the port have small spaces. A low power consumption is also desirable for longer operation periods without frequent battery replacements or excessive energy supply requirements, especially for fixed ADCPs that may not have easy access to a continuous power source.

Besides, low cost is necessary for large-scale deployment of measurement equipment in the port. The Titanium alloy casing ADCPs are highly recommended. Several outstanding advantages of titanium alloy include that it is very resistant to corrosion and thus could withstand seawater for long periods without corrosion after some time that would lead to losing integrity and performance in an ADCP flow meter. The material also has a high strength-to-weight ratio; this can be a very durable, light-weight design. It can also resist higher pressures at greater depths, making it capable of being applied in the different water depth conditions in the port area.

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

Based on Usage

Shipborne ADCP: In the case where the main purpose is to have a wide-area proper understanding of current patterns during vessel operations, shipborne ADCPs will be a good choice. Since the ship will go around, it can cover different regions and provide lots of data for analyzing the overall current situation.

Bottom-mounted (Sitting on the seabed) ADCP: In cases where long-term and continuous monitoring of the current condition is required at specific fixed locations, such as near important port structures or in areas where the current characteristics are of particular interest for research or operational reference, bottom-mounted ADCPs are more suitable. They can provide stable and consistent data over an extended period.

Buoy-mounted ADCP: Where the measurement of currents is to be done in some specific area that is not very accessible either by fixed installations or by ship operations, buoy-mounted ADCPs can be used. They can drift with the currents to some extent while collecting data on the variations of the currents in those specific areas.

Based on Frequency

When the depth of the water is within 70 m, an ADCP meter of frequency 600 kHz can be enough in many cases. The latter can provide detailed and correct current measurements in the relatively shallow areas of the port.

For water depths up to 110 meters, a 300 kHz ADCP is preferable as it can effectively penetrate the water column to obtain reliable current data at those depths.

For deeper areas, with water depths reaching 1000 meters, an ADCP with a frequency of 75 kHz is recommended since it can cover such large depth ranges and still measure the ocean currents with acceptable accuracy.

There are some famous brands in the market, including Teledyne RDI, Nortek, and Sontek. However, here I would like to introduce a high-quality and economic Chinese ADCP brand: China Sonar PandaADCP. It is made of all-titanium alloy material, featuring excellent durability with the advantage of light weight. In addition, it has an incredible price-performance ratio. For more detailed information, you can pay a visit to its official website: https://china-sonar.com.

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