ADCP's Application to Ocean Current Measurement in Basco Port

1. Where is Basco port?

Basco port is in the municipality of Basco, which is located on Batan Island in the Batanes province of the Philippines.

Port Scale and Throughput

It is a major port catering to the local community and a conduit for regional trade links. Although it does not boast a scale similar to that of some international major ports, it caters well to the import and export needs for the basic commodities that are vital for the islanders. Its throughput mainly includes items like food supplies, construction materials, and some local products for export. Over time, the port authority has been gradually expanding its capacity to cater to the growing demands in the area.

Routes and Business

It has connections with other Philippine ports mainly to bring goods to and from the main islands. Locally, the port serves as an outlet for the delivery of basic needs to Basco and its environs. On the commercial side, it provides services such as cargo vessel loading and unloading, warehousing of goods in transit, and customs clearance procedures in coordination with the proper authorities.

Port Management and Operation

The local port authorities manage the port and are responsible for its smooth running. They are responsible for vessel scheduling, maintaining the safety and order of the port area, and ensuring that the upkeep of port facilities is well kept. Inspections and maintenance works are regularly undertaken to keep the port in decent working condition.

Port Facilities

The Basco port has a facility with berthing facilities that can accommodate vessels operating within the area of varying sizes. A warehouse for storage purposes and handling equipment is helpful during loading and unloading. Other facilities also include the delivery of some basic services to the ships, like refueling and fresh water.

Channel and Direct Shipping

It has a well-defined channel where ships can safely enter and leave the port. Improvements in the channel are constantly being made to have the appropriate depth and width of water to allow the smooth passage of vessels. Although not as many direct routes are found here compared to the major ports, it has established regular connections with the key ports in the Philippines to be able to service the trade and transportation requirements.

2. Why should we measure ocean currents in Basco port?

Measuring ocean currents in Basco port bears some important implications concerning its operation and management of this particular port. To begin with, exact current data allow improvements in the safety of ships while navigating within the area of the port. Knowing the direction and velocity of the currents allows the port pilot to guide the vessels more precisely during their berthing and departure procedures, reducing the risk of possible accidents such as collisions against the port structures or other ships.

 It is also useful in optimizing the layout of the port and its future development process. Understanding the flow patterns of the ocean currents may help in finding the most suitable places for new berths, docks, or other infrastructure expansions so that they can be structurally designed to resist hydrodynamic forces exerted by the currents. Current knowledge is, thirdly, of much importance in properly carrying out port services for scheduling purposes with regard to cargo-handling operations; such information would aid in the estimation of their impact on ship movements and, hence, the loading/unloading times.

In this respect, Acoustic Doppler Current Profiler(ADCP) is more advanced and easier to measure compared to the traditional methods. It can also quickly and precisely collect detailed current information at different depths, which provides critical real-time data that is essential for the smooth running of the Basco port.

3. How do ADCPs using the Doppler principle work?

The working of ADCP is based on the principle of the Doppler. It sends acoustic signals into the water column. These acoustic waves interact with the suspended particles or any other element in the water that will scatter the acoustic energy. The frequency of these reflected sound waves, by such moving particles entrained in the movement of the ocean current, is altered through a principle related to the Doppler effect. Thus, by precisely measuring this change in frequency, the ADCP will calculate the speed of an ocean current at varied depth points within its measurable depth.

ADCP in port ocean current measurement: ADCP onboard.

The shipborne ADCP is installed on vessels operating within the Basco port area. While navigating, the ADCP steadily sends acoustic signals in several directions. It can gather the current data at several points along the path of the ship to form a picture of the ocean current distribution across different regions of the port area. It enables one to fully understand the current situation in a relatively large area covered by the movement of the ship.

Fixed ADCPs are generally installed at known positions inside the port complex, usually in specified positions on the sea bottom along important facilities or other sections of interest across the fairway. Thus, a fixed device stays there while measuring current conditions consistently over a long period. Data so provided are coherent along the temporal dimension, hence a value added for investigating the normal trends in the current regimes and understanding their possible interaction with installations and the whole operation done in correspondence at those specific positions.

4. What is necessary in having fine measurement for Basco port currents?

Basically, to enable high-quality measurements of ocean currents in the port of Basco, the equipment needs some essentials for quality and proper operation: the materials for its building should be reliable. The materials should be such that in the aggressive marine environment with saltwater corrosion, different water pressure, and continuous wave action, their performance should not deteriorate with time, and the performance of the measuring device should not be affected.

Smaller size, lighter weight, and lower power consumption are very desirable. The size will be compact, hence making it easier to install in different locations within the port on ships or at fixed points. The lower weight facilitates handling and deployment, while reduced power consumption ensures continuous operation without frequent power source replacements or excessive energy demands. Thirdly, cost-effectiveness enables large-scale measurement across the port.

In regard to casing, ADCP is excellent in titanium alloy. Titanium alloy has a number of advantages: it has high strength that can bear the mechanical forces exerted by the marine environment. Due to its excellent corrosion resistance, it is very suitable for serving a long time in seawater and protects the inside components of the ADCP from being damaged by the corrosion of saltwater. Its relatively low density results in a lighter casing compared with many other materials of similar strength, which agrees with the requirement for light-weight equipment.

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

According to the Usage Purpose

• Shipborne ADCP: If the intention is to make dynamic measurements while the ship is in motion around the Basco port area for a rapid view of the current conditions in different sections of the port, then shipborne ADCP is the best option. It will cover a large area during the normal operation of the ship.
• Bottom-mounted ADCP: Bottom-mounted ADCP applies to locations where long-term and continuous monitoring of the ocean current is to be done at a specific fixed location in the port. For example, near berths or structures where, due to the impact of currents, close observation is required. Provides stable and consistent data at that particular position over an extended period.
• Buoy-mounted ADCP: Buoy-mounted ADCP is used when it is inconvenient to install fixed equipment on the seabed or on other structures. The buoy floats on the water surface, and the ADCP on it can measure the ocean current in the upper layers of the water body and transmit the data wirelessly, offering flexibility in data collection.

According to Different Frequencies

• Generally, 600 kHz ADCP will suffice in the water depths within 70 meters in the Basco port area, as it can give quite accurate measurements of the characteristics of ocean currents for this relatively shallow depth.
• For a water depth of about 110 meters, 300 kHz ADCP serves better because it is designed for the capture of current details at this depth.
• Where deeper water areas with water depths up to 1000 meters are encountered, a 75 kHz ADCP will have to be selected since it can give better penetration in the water to get reliable current information.

Several brands exist, and quite a few are well recognized in the market. Teledyne RDI, Nortek, and Sontek are just a few to name. But one Chinese brand of ADCP deserves mention: China Sonar PandaADCP. Manufactured from all-titanium alloy materials, not only does it ensure a long service life and an excellent performance in the marine environment, but also provides a very attractive cost-performance ratio. You can learn more about it from its official website: https://china-sonar.com/.

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