01202 932933

Office 01202 932933


 01202 932690

Emergencies  01202 932690

In-Water Bottom Surveys and Ship Inspections

In-Water Bottom Surveys conducted by UK Diveworks Commercial

Based in Poole, UK Diveworks Commercial is perfectly situated between Portland Harbour, Southampton Dock and Portsmouth Harbour, to carry out in-water surveys. A variety of vessels visit the ports daily and include cruise liners, container ships and work vessels.

Our In-water bottom surveys can often speed up inspection times and allow ship owners to avoid costly haul outs and dry dock situations. These ship surveys highlight any damages, safety issues and allow the reporting of the condition of vessels. Shipping is a fast-paced industry that relies upon knowledgeable, professional dive teams to perform a variety of tasks.

Supported by our integrated Diver HD video systems and communications recording, Classification Surveyor's control the inspection programmes. Our dive teams have years of experience and understanding of the inspection process and the types of vessels to be inspected. UK Diveworks Commercial's Managing Director Daniel Walters has been a regular visitor to the underside of the Queen Elizabeth Air Craft Carrier, the largest vessel within the Royal Navy's fleet.

A post-works report can be supplied outlining any defects of concern

Book an In-Water Bottom Survey today

Accompanying all of our in-water bottom surveys, our clients are supplied with:

Types of In-water Bottom Surveys

UKD Commercial Ltd, a team of expert and professional UK divers, provides in-water bottom surveys, also referred to as underwater hull inspections.

An in-water bottom survey or underwater hull inspection is a comprehensive examination of a ship´s submerged hull, propellers, and related underwater components while the vessel is afloat. This critical maritime procedure is conducted to assess the condition of these submerged parts, ensuring the vessel´s safety, operational efficiency, and compliance with regulatory requirements.

The significance of in-water bottom surveys or underwater hull inspections for ship owners and operators cannot be overstated.

In-water bottom surveys or underwater hull inspections serve multiple crucial purposes:

1. Safety Assurance:
Ensuring the structural integrity of a ship´s hull and underwater components is paramount for the safety of the vessel, its crew, and any cargo it may carry. Detecting and addressing potential issues in a timely manner helps prevent catastrophic accidents.

2. Operational Efficiency:
A well-maintained hull and propellers contribute to improved hydrodynamics, reduced frictional resistance, and lower fuel consumption. This optimization enhances the vessel´s overall operational efficiency, reducing operating costs.

3. Environmental Compliance:
Compliance with environmental regulations is a top priority in the maritime industry. In-water bottom surveys help monitor the condition of anti-fouling coatings, which are essential for preventing the attachment of marine organisms to the hull, and they ensure compliance with measures to prevent marine pollution.

4. Asset Preservation:
Identifying and mitigating corrosion, fouling, or other structural issues early on can significantly extend the service life of the vessel. This not only preserves the asset´s value but also reduces the need for costly and extensive repairs.

The UKD Commercial team follows professional procedures when carrying out an in-water bottom survey or underwater hull inspection, a multi-faceted process that involves a series of meticulously planned and executed steps:

Pre-Survey Planning:

Survey Scope Determination:
Shipowners or operators, in consultation with marine surveying experts, define the scope and objectives of the survey. This includes specifying the inspection´s extent and the type of equipment and personnel required.

Regulatory Compliance:
Ensure that the survey complies with relevant international and local regulations, as well as the ship´s classification society requirements.

Safety Preparations:
Prioritize safety by conducting risk assessments and implementing safety protocols. This includes briefing diving teams or remotely operated vehicle (ROV) operators on emergency procedures and safety equipment.

Equipment and Personnel Deployment:

Diving Teams or ROVs:
Depending on factors such as vessel size, location, and accessibility, professional divers or ROVs are deployed to perform the inspection. Each option has its advantages and limitations.

Equipment Setup:
Divers or ROVs are equipped with specialized tools, high-resolution cameras, sonar, and measurement devices tailored to the specific in-water bottom survey requirements.

Hull Inspection:
Visual Examination: The initial step involves a visual inspection of the hull’s exterior. During the underwater hull inspection divers or ROVs systematically examine every inch of the hull, paying close attention to areas prone to damage or corrosion.

Coating Assessment:
Assess the condition of anti-fouling coatings, protective paints, and anodes. Any signs of deterioration, peeling, or damage are documented.

Anomalies Detection:
A detailed examination is conducted on weld seams, through-hull fittings, propellers, rudders, and other critical components. Any anomalies, such as cracks, pitting, or deformation, are meticulously documented.

Thickness Measurements:
Ultrasonic thickness gauges are employed to measure the thickness of the hull’s plating. This data is invaluable for detecting areas of thinning due to corrosion or wear.


Comprehensive Records:
UKD Commercial generate detailed reports, encompassing written descriptions, annotated photographs, and high-definition videos. These records provide a clear and comprehensive overview of the vessel’s condition, pinpointing areas requiring attention.

Data Analysis and Recommendations:
Expert Assessment: UKD Commercial Marine surveyors, often working in collaboration with naval architects and engineers, analyze the collected data. They assess the severity of any issues and their potential impact on the vessel´s safety and performance.

Based on the findings of the in-water bottom survey or underwater hull inspection, UKD Commercial provides recommendations for maintenance or repairs. These recommendations may range from routine cleaning and repainting to more extensive repairs, such as welding or replacement of damaged components.

Compliance and Reporting:

Environmental Compliance:
In-water bottom surveys also ensure compliance with environmental regulations governing anti-fouling coatings, ballast water, and other potential sources of marine pollution.

Regulatory Reporting:
Depending on the vessel´s type and operations, survey results may need to be reported to maritime authorities or classification societies to demonstrate compliance with safety and environmental standards.


UKD Commercial fulfilling compliance requirements for an in-water bottom survey or underwater hull inspection:
Compliance requirements for an in-water bottom survey or underwater hull inspection can vary depending on factors such as the type of vessel, its size, its intended operations, and the governing regulations of the maritime authority or classification society to which the ship adheres.

However, there are some common compliance requirements that are often applicable:

International Maritime Organization (IMO) Guidelines:

1. The IMO provides guidelines and recommendations for the conduct of in-water bottom surveys through various conventions and codes, such as the International Convention for the Safety of Life at Sea (SOLAS). Compliance with these guidelines is essential for ensuring the safety and seaworthiness of vessels.

2. Classification Society Rules:
Many vessels are classed by classification societies (e.g., Lloyd´s Register, DNV, ABS). These societies have their own rules and regulations regarding the frequency and standards of in-water bottom surveys. Compliance with the rules of the relevant classification society is often a requirement for maintaining class status.

3. Flag State Regulations:
The flag state of a vessel may have specific regulations related to in-water bottom surveys. Flag states issue certificates of compliance and may require surveys to be conducted at specified intervals.

4. Port State Control:
Port state authorities in the ports a vessel visits may have their own requirements for surveys and inspections. Compliance with these requirements is necessary to avoid delays or penalties when entering certain ports.

5. Environmental Regulations:
Compliance with environmental regulations is crucial, especially in relation to anti-fouling coatings and the prevention of marine pollution. Regulations such as the International Convention on the Control of Harmful Anti-fouling Systems on Ships (AFS Convention) restrict the use of certain types of anti-fouling paints.

6. Ballast Water Management:
Compliance with regulations related to ballast water management is essential. The International Convention for the Control and Management of Ships´ Ballast Water and Sediments (BWM Convention) establishes standards for the treatment and discharge of ballast water to prevent the spread of invasive species.

7. Safety of Life at Sea (SOLAS):
SOLAS regulations require ships to be maintained in a seaworthy condition, which includes the regular inspection and maintenance of hulls and related components. Compliance with SOLAS requirements is crucial for safety.

8. Regional Regulations:
Depending on the geographic area in which the vessel operates, there may be regional regulations and requirements that need to be met. For example, some areas have specific regulations related to biofouling prevention.

9. Insurance Requirements:
Some insurers may have specific requirements regarding the frequency and scope of in-water bottom surveys or underwater hull inspections as a condition of insurance coverage. Compliance with these requirements is essential to maintain insurance coverage.

UKD Commercial reiterate the importance for shipowners, operators, and ship captains to be aware of the specific compliance requirements that apply to their vessels and operations. Non-compliance with these requirements can result in a range of consequences, including the loss of class status, fines, detention of the vessel, and damage to a vessel´s reputation. Therefore, staying informed about and adhering to the relevant regulations and guidelines is essential for the safe and compliant operation of maritime vessels. UKD Commercial will consult with classification societies, flag state authorities, and experienced marine surveyors to ensure that all compliance requirements are met.

UKD Commercial concludes that an in-water bottom survey is a meticulous and indispensable procedure for ship owners and operators to maintain the safety, operational efficiency, and regulatory compliance of their vessels. UKD Commercial can provide the necessary well-organized and systematic effort, combining expert personnel, specialized equipment, and thorough documentation. The proactive nature of these surveys allows shipowners and operators to address any issues promptly, preserving the vessel´s operational lifespan, safeguarding the environment, and ensuring the safety of all those aboard.

Contact us

Office    01202 932933

Emergencies   01202 932690

(this number operates 24/7)