Underwater Salvage Operations

Salvage of Sunken Pipeline at Paradip Port Trust (2006)

A sunken pipeline (900/800 mm diameter) located in the navigational channel of Paradip Port Trust was successfully removed by employing underwater cutting, airlift bags, and transportation to Paradip Yard.

•   The pipeline, measuring 98 meters in length, was embedded in the seabed at a depth of 10 meters below sand.
•   Removal of over burdened material of the buried pipeline by de-siltation method.0
•   The operation involved underwater cutting (u/w cutting), whereby the pipeline was cut into 6 sections for manageable retrieval.
•   To assist in lifting the heavy pipeline sections, airlift bags (4 units, each with a 10-ton capacity) were used. These provided sufficient buoyancy to lift the segments from the seabed.
•   After surfacing, the sections were transported to the dock yard and further transferred to the shore using cranes

Salvage Operation of Dredging Arm of Dredger at Sea (2007)

successful salvage operation of the dredging arm of a dredger was carried out at sea, involving the following key steps:

•   Disconnection of Dredging Arm: The dredging arm was disconnected above water level using surface Oxy-Arc cutting techniques to ensure safe and precise separation.
•   Recovery Process: The dredging arm was recovered using air lift bags with a lifting capacity of 10 tons. This method provided controlled buoyancy and stability during the lifting operation.
•   Transportation: The salvaged dredger arm was carefully floated and maneuvered to the Krishnaatnam Port Jetty.
•   Handover: Upon reaching the jetty, the dredger arm was safely lifted over and formally handed over to the concerned party.

This operation highlights the effective use of marine salvage techniques and equipment in challenging offshore conditions.

Salvage of 20-Ton iron boat at Ballimela Reservoir-Odisha (2008)

On 29 June 2008, the Balimela Reservoir boat attack took place in Odisha, India, when the Communist Party of India (Maoist) forces ambushed a boat carrying 60 Greyhounds commandos, 5 police officers and a boat operator. The ambush led to the sinking of the boat, resulting in the deaths of 38 individuals, while 27 survived.

Following the attack, a week long search operation was conducted in collaboration with Naval forces. Sea Lion Offshore Diving team played a crucial role in this operation. They successfully located the sunken boat at a depth of 25 Meters in the Balimela reservoir. Utilizing specialized underwater divers and airlift bags, the team conducted a systematic salvage operation. As a result, they recovered both the dead bodies and the sunken boat, which were handed over to government authorities for further investigation.

Sea Lion Offshore Diving is well experimented in medium-size maintenance & installation projects

Srisailam Dam-2009 Flood

Retrieval and Erection of Draft tube Gates from Surge Pool at Srisailam Dam – 2009 Flood Operation

•   During the heavy floods of 2009, Sea Lion Offshore Diving Pvt. Ltd. carried out a critical underwater operation for the retrieval and re-erection of DT gates from the surge pool of Srisailam Dam, located at a depth of 60 meters.
• A total of 10 DT gates of 30 pieces with each piece weighing approx 7-Ton were recovered from the surge pool using airlift bags, which provided controlled buoyancy for lifting the heavy structures from the significant depth.
•   Following successful retrieval, all 30 pieces were re-erected in the surge pool, again using airlift bags to assist in accurate positioning and controlled assembly.
•   This operation was a key emergency intervention, demonstrating the capability to handle large-scale, high-pressure underwater tasks during critical situations, ensuring structural and operational stability of the surge pool.

This operation highlights the effective use of marine salvage techniques and equipment in challenging offshore conditions.

First Pilot Project of Fish Cage Installation at Sea in India by CMFRI

The Central Marine Fisheries Research Institute (CMFRI) successfully implemented India’s first pilot project for the installation of a fish cage at sea near Visakhapatnam. The project was executed in collaboration with Sea Lion Offshore Private Limited.

A key technology used in this project involved the placement of 10-ton concrete blocks at precise locations on the seabed using air lift bags. These heavy blocks served as anchors to fix the fish cage structure securely in position at sea, ensuring stability and durability under marine conditions.

This pioneering effort marks a significant step towards developing sustainable aquaculture practices in India’s marine waters and demonstrates the successful application of advanced offshore engineering techniques for aquaculture infrastructure.

•   Towing of 18-ton anchor blocks for the fish cage anchoring project at sea, Visakhapatnam – CMFRI Project.
• Towing of 09-ton anchor blocks for the fish cage anchoring project at sea, Visakhapatnam – CMFRI Project.
•   Installation of fish cages (cage culture) at sea, Visakhapatnam – CMFRI Project.

Breakwater installation using Geotubes at Poonthura Beach NIOT Project (Nov-2020 to May-2021)

Sea Lion Offshore Diving Pvt. Ltd. provided specialized diving support for the installation of a geotube breakwater as part of the NIOT (National Institute of Ocean Technology) project at Poonthura Beach

•   The project involved the placement of GEO bags to form a breakwater structure, aimed at coastal protection.
•   Sea Lion Offshore Diving Pvt. Ltd. employed airlift bags to accurately position and place large blocks underwater during the construction process.
•   In addition, the company provided expertise in lifting heavy blocks (10-ton capacity) related to a dredging pipeline operation, ensuring safe and precise handling of heavy components underwater.

This operation was critical in ensuring the stability of the breakwater structure and efficient execution of the NIOT coastal project.

Retrieval of Draft Tube Gates from Surge Pool at Srisailam Dam Left Bank (Feb-2023)

Sea Lion Offshore Diving Pvt. Ltd. successfully executed a complex underwater operation involving the retrieval of 2 DT gates from the surge pool of the Srisailam Dam, located at a depth of 40 meters.

•   The operation involved underwater cutting of 64 mm thick gate structures into manageable segments. Each gate was cut into 3 parts at slice joints, resulting in a total of 6 parts.
•   Each individual part weighed approx. 7 tons
•   The experienced technical diving team employed airlift bags to lift and safely bring the heavy segments to the surface.
•   The operation was carried out with precise planning and execution, ensuring safe handling of large structural components from significant depth, while maintaining structural integrity and environmental safety.

Erection of Draft Tube gates at Srisailam Dam Left Bank
(April-June-2023)

Sea Lion Offshore Diving Pvt. Ltd. successfully executed a complex and challenging underwater operation involving the erection of 2 gates in the surge pool of Srisailam Dam, at a depth of 40 meters.

•  Each gate was composed of 8 parts, with an approximate weight of 8 tons per part.
•  The heavy gate segments were carefully transported underwater using airlift bags, providing controlled buoyancy and precise maneuverability.
•  The team of experienced technical divers performed accurate underwater assembly and joining of the gate parts.
•  Once assembled, the gates were successfully erected in position within the surge pool, ensuring correct alignment and structural stability.

This operation highlights Sea Lion Offshore Diving’s expertise in executing large-scale underwater installations with precision, heavy lifting, and complex assembly at significant depths.

Salvaging of Struck Boats at Prakasam Barrage –
September 2024 Krishna River Flood Operation (Sep-2024)

During the heavy floods in the Krishna River in 2024, 4 boats got stuck against the dam gates of Prakasam Barrage, posing a serious risk to the structure and flood management operations.

Sea Lion Offshore Diving Pvt. Ltd. was engaged to provide specialized diving and rigging support for the safe recovery of all 4 boats.

•   The experienced diving team, supported by the rigging crew, carried out a systematic and careful underwater cutting and salvage operation.
•   The operation was executed with precision to ensure no damage to the dam structure, preserving its integrity and functionality.
•   All 4 boats were successfully recovered and salvaged from the dam gates.
•   The recovered boats were handed over to the government authorities following proper protocols

This operation exemplifies Sea Lion Offshore Diving’s expertise in emergency underwater salvage work, heavy lifting, and structural preservation under challenging flood conditions.