ADCP's Application to Ocean Current Measurement in the Port of Warrenpoint

1. Introduction to the Port of Warrenpoint

The Port of Warrenpoint is a port located in County Down, Northern Ireland. This port is considered one of the most important in this locality and thus plays an indispensable role in the regional maritime trade.

Port Scale and Throughput

• The port has a medium-scale size. The cargo it handles is varied, ranging from agricultural products to building materials and industrial goods. The volume is relatively high, considering the level of trade passing through the port, catering to both the domestic and international markets.
• It has a number of berths with different characteristics, allowing the reception of ships of different sizes. From vessels of smaller dimensions used in local trade to larger cargo ships involved in international shipping, the infrastructure of the port allows it to handle this traffic effectively.

Routes and Business

• Domestically, the port is well linked with other ports in the UK and Ireland. Internationally, it has trade relations with various ports in Europe and beyond. The core activities include cargo handling, storage, and distribution services. It is one of the major ports participating in the importation and exportation of goods like grains, fertilizers, and manufactured goods.
• It also provides support for the local fishing industry and has facilities for fish processing and storage. Besides, the port provides services concerning ship maintenance and repair.

Management and Operation of the Port

• The port has a professional management team that manages all aspects of the port. This includes berthing arrangements for ships, coordination in the loading and unloading of cargo, and safety and security matters of the port area.
• The management works in close coordination with shipping companies, customs authorities, and other port-related services. They are also responsible for maintaining and upgrading the port facilities to meet the evolving demands of the shipping industry.

Port Facilities

• Has facilities that are fully equipped within them; there are berths where vessels can be accommodated with adequate depths. For these processes to be smoothly executed, appropriate and advanced cargo-handling facilities comprise equipment with cranes and forklifts.
• The port has large storage facilities, with general cargo warehouses and silos for bulk cargo. Other facilities include ship refueling, water supply, and basic maintenance services. Facilities for the crews and personnel who work at the port include rest areas and cafeterias.

Channel and Direct Navigation

• The port has a well-maintained channel that allows the entry and exit of ships safely. The channel is dredged periodically to retain the depth required for ships of different drafts. Navigation aids such as buoys, lights, and radar systems are in place to guide the ships during approach and departure. This enables direct navigation for vessels coming from different directions across the Irish Sea and other connected waterways.

2. Importance of Measuring Ocean Currents in the Port of Warrenpoint

Navigation Safety

• It is important that ocean currents in the Warrenpoint Port are measured regarding the safety of the ships. Current patterns in the Irish Sea can be complex and variable, with knowledge of these currents an important factor in safe navigation.
• For instance, during docking and undocking, a strong and unpredicted current may blow a ship off course. With proper current information provided, captains of the ships would, in turn, be able to modify their speed and course to a position where collisions with other vessels or running aground could be evaded.

Efficient Port Operations

• It helps in understanding the ocean currents for the smooth functioning of the port. The authorities can then schedule the arrival and departure of ships accordingly. The ships can thus avail the facility of favorable currents, saving on fuel while docking and undocking.
• This also helps in the optimization of port resources. For example, if the current is flowing in a direction that assists the movement of ships to a particular berth, then the loading and unloading process can be more efficient.

Environmental Protection

• Currents are extremely essential for the dispersion of all the pollutants in the port area. In any spillage of oil or even the release of other chemicals, dispersion will depend on current to plan effective containment and clean-up measures.
• Disposal of wastewater and others is well managed by taking account of the current pattern within that area, allowing minimizing effects on the marine environment.

Infrastructure Maintenance

• Currents can exert forces over time on structural elements of port infrastructure such as breakwaters and quay walls, and the measurement of currents provides valuable data in the long-term planning and maintenance of such structures.
• For instance, if the currents are consistently strong in that area, additional reinforcement may be necessary to prevent erosion and damage to the quay walls. Acoustic Doppler Current Profiler (ADCP) is a more advanced and convenient way of measuring ocean currents compared to the traditional methods.

3. How ADCPs Using the Doppler Principle Work

The principle behind the working of ADCPs is the Doppler principle. They send out acoustic signals into the water. The acoustic waves interact with the moving particles in the water-sediment, plankton, or other small organisms carried by the ocean current. On their return, the frequency of the reflected waves is changed.

This change in frequency is known as the Doppler shift and is directly proportional to the velocity of the moving particles and, hence, the velocity of the ocean current. ADCPs possess multiple transducers that emit and receive these acoustic signals in different directions. By measuring the Doppler shift from multiple directions-which usually comes in either a three-dimensional or two-dimensional configuration, the ADCP flow meter can calculate the speed and direction of the ocean current at different depths.

ADCP in Port Ocean Current Measurement

Shipborne ADCP

• Shipborne ADCPs are installed on vessels. While the ship is in motion, the ADCP current meter sends out acoustic signals continuously downwards and sideways. It collects data on the current velocity as the ship navigates through different areas of the port.
• The advantage of this technique is that it is mobile. It can take up to a wide range of measurement within the port waters. However, the own motion of the ship needs to be taken into consideration for proper result acquisition. Calibration and compensation techniques correct the errors caused by the movement of the ship.

Fixed ADCP

• Fixed ADCPs are fitted at specific locations in the port, like on the seabed or fixed platforms, such as piers and buoys. They continuously view the ocean current at that same point over an extended interval.
• This provides long-term and consistent data for understanding the regular current patterns in a specific area of the port. The drawback is that they only cover a very limited area around their installation location, but they are of great utility in establishing reference current data for particular regions within the port.

4. Requirements for High-Quality Measurement of Currents in the Port of Warrenpoint

Equipment Materials

• To attain high-quality measurement of the ocean currents in the Warrenpoint Port, the equipment materials used should be of a reliable nature. Considering that seawater is corrosive and may have floating debris, which could cause impacts, a durable material is necessary.
• The instrument must withstand the Irish Sea marine conditions and not drift too much over time. Titanium alloy casings are an excellent option for ADCPs with great corrosion resistance in seawater.

Compact and Lightweight Design

• The size of the equipment should be small to facilitate easy installation, especially in areas with limited space such as on small buoys or in regions with complex underwater structures.
• A lightweight design is also beneficial as it simplifies the installation and maintenance processes. This is particularly important for equipment that may need to be deployed and retrieved frequently.

Low Power Consumption

• Low power consumption is essential, especially for long - term monitoring. Equipment that requires high power may find it difficult to operate constantly because of the limited availability of the power supply in the port area or frequent battery replacement may be required.
• This is the case for fixed ADCPs that are intended to monitor continuously over long periods of time.

Cost Effectiveness

• Cost-effectiveness is also a factor. For comprehensive current measurement in the port, affordable equipment allows for more extensive deployment, enabling a more thorough understanding of the current conditions throughout the port waters.
• This is important for a port like Warrenpoint to optimize its resources and make informed decisions about current measurement strategies.

5. How to Choose the Right Equipment for Current Measurement

Based on Usage Purpose

• Shipborne ADCP: Where the intention is to have current data over an extensive area of the port when the ship is in use-for example, in periodic port surveys or data acquisition related to the update of navigational charts-use shipborne ADCPs. These can cover different areas of the port as the ship moves around.
• Bottom-mounted (Sitting) ADCP: When the nature of monitoring requires long-term and fixed-point monitoring of specific locations within the port, such as near critical infrastructure like breakwaters or at the entrance of the port channel, bottom-mounted ADCPs are suitable. They provide stable and continuous data for understanding the local current characteristics.
• Buoy-mounted ADCP: For areas where it is not convenient to install fixed equipment on the seabed or on structures, or when a floating monitoring point is needed for capturing surface and near-surface current conditions, buoy-mounted ADCPs are used.

Based on Different Frequencies

• A 600kHz ADCP will often be appropriate in water depths of within 70m, while generally providing reasonably high resolution of the current profile in shallower water-which would be sufficient in the large areas of most port areas where water depth may not be exceptionally great away from the immediate area adjacent to the quay walls into inner harbor areas.
• In the case of water depths up to 110m, a 300kHz ADCP is more appropriate. It can effectively penetrate the water column at these depths and accurately measure the current velocities.
• For much deeper areas, such as the approach channel of the port where the water depth might be over 1000m, a 75kHz ADCP is recommended. At this lower frequency, it should be able to reach farther down and still obtain information on currents.

There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. On the other hand, to those looking out for a budget-friendly unit with excellent quality, they might look at the option of China Sonar PandaADCP. It would be of all-titanium alloy material, durable while having a great performance. With great cost, the performance offers a choice for ocean current measurement at the Port of Warrenpoint. You can learn more about it on its official website: (https://china-sonar.com/).

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