Dredging360.com

General properties
Vessel type: TSHD
Flag: LU
Manager: DEME - Dredging Environmental and Marine Engineering N.V.
Built in: 2018
Shipyard: Cosco (Guangdong) Shipyard Co. Ltd
Yard number: CO. 1288
Design by: C-JOB naval architects / engineers
Physical properties
Hopper volume: 15000 m³
Dredging depth (extended): 102 m

We will soon welcome another pioneering vessel in our fleet. Sea trails kicked off with newbuild 15,000 m3 trailing suction hopper dredger ‘Bonny River’ near Dawanshan Island in the South China Sea. The technically smart designed vessel combines various innovative features, such as the capability to dredge very hard soil and the ability to work in water depths of up to 100 m. #DEMEGroup #RoyalIHC #TSHD #dredging

DEME, an international group of specialized companies involved in complex marine engineering works, said in the latest release that sea trails of their newbuild 15,000m³ trailing suction hopper dredger (TSHD) Bonny River has officially started near Dawanshan Island in the South China Sea.

“The technically smart designed vessel combines various innovative features, such as the capability to dredge very hard soil and the ability to work in water depths of up to 100m,” DEME said.

The TSHD Bonny River was launched in April 2018 at COSCO Guangdong Heavy Industry shipyard in China.

According to DEME, the dredger will be able to minimize the turbidity generated by process water and enables dredging in environmentally vulnerable areas.

The hydrodynamic hull and the dual-fuel engines (diesel and LNG) will ensure further optimization of the fuel consumption and a minimal CO2 footprint.

Thanks to the hull’s optimized design, the dredger will have a transport capacity of 24,000 tonnes. Having a limited depth when loaded, the newbuild will be highly suitable for coastal protection assignments, even in regions with shallow beaches.

Welcome ‘Bonny River’! The newest addition to our fleet has arrived! The next generation trailing suction hopper dredger ‘Bonny River’, featuring DP2 and packed with innovations, can dredge very hard soils and can work in deep waters of more than 100 m. Our new dredger is currently being mobilised in Vlissingen, the Netherlands and will soon head to the New Lock Terneuzen for reclamation works and to the Belgian North Sea for backfilling trenches at Elia’s Modular Offshore Grid project. #TSHD #DEMEGroup #dredging #Elia #NieuweSluisTerneuzen

DEME’s multi-year fleet investment program continues with the arrival of the new generation trailing suction hopper dredger ‘Bonny River’.

The arrival of the 15,000m³ ‘Bonny River’ marks the introduction of a new generation of trailing suction hopper dredgers (TSHD). This vessel is able to dredge very hard soils and can work in deep waters of more than 100m.

The new dredger combines a very long suction pipe and large carrying capacity, with a limited draught. Additionally, the TSHD has a heavy-duty trail pipe with a rock draghead.

Environmental innovations

‘Bonny River’ has a large jet pipe on her suction tube that uses extracted overflow water from the hopper that is pumped back to the seabed and integrated into the dredging process.

LNG World News: LNG-powered dredger joins DEME’s fleet

LNG-fueled trailing suction hopper dredger Bonny River has joined the fleet of Belgian dredging specialist DEME.

DEME said on Monday that Bonny River joined the company’s fleet and was being mobilized in Flushing, The Netherlands, for its first assignments.

The vessel with a 15,000-cbm capacity is capable of dredging hard soil and can work in water depths up to 100 meters, DEME said in a brief statement through its social media channels.

Bonny River, with dual-fuel engines using diesel and LNG as fuel, will carry a ‘Green Passport’ and ‘Green Design’ classification.

The order for the Bonny River has been placed at Royal IHC, and the ship has been built by Cosco at its shipyard in Guangdong, China.

DEME added that it also had three other dredging vessels under construction, including another LNG-powered vessel Spartacus – the most powerful cutter suction dredger in the world – and trailing suction hopper dredgers Meuse River and River Thames.

It is worth reminding that the Bonny River was launched at COSCO’s Guangdong Heavy Industry shipyard in China in April 2018. The vessel started sea trials in the South China Sea in late February 2019.

This enables the vessel to achieve ‘closed loop dredging’ whereby the turbidity generated by the process water is eliminated, which is particularly important in environmentally sensitive areas.


Image source: DEME
Moreover, the shape of the hull and two-speed propulsion gearbox reduce fuel consumption considerably, said the company.

‘Bonny River’ is a full DP2 trailing suction hopper dredger – the first of its kind – which allows the vessel to manoeuvre with pinpoint precision. The vessel has a ‘Green Passport’ and a ‘Clean Design’ notation.

First projects in the Netherlands and Belgium

Currently, ‘Bonny River’ is preparing in Flushing for her first assignments.

The vessel will reclaim approximately 300.000 m³ of sand at the New Lock Terneuzen project in the Netherlands. With the reclamation the first phase of the plateau will be realized from which the new lock will be built.

The reclamation will be combined with deepening works in the outer harbor of Terneuzen.

The official naming ceremony for ‘Bonny River’ will take place later this year.

Fleet investment program

With continued investment in its fleet, DEME aims to take the lead in the industry with vessels featuring innovative technologies and improved operational performance.

Three other dredging vessels are under construction, including ‘Spartacus’ – the most powerful cutter suction dredger in the world – and trailing suction hopper dredgers ‘Meuse River’ and ‘River Thames’.

The trailing suction hopper dredger (TSHD) “Bonny River”, built at Royal IHC’s Chinese partner yard COSCO Guangdong Shipyard, is propelled by SCHOTTEL. Recently handed over to the Belgian dredging company DEME, the TSHD is driven by controllable pitch propellers and transverse thrusters from the German propulsion expert. With a 15,000 cbm capacity, the vessel is capable of dredging hard soil and able to work in water depths of more than 100 m.

Jan Gabriel, Head of the Technical Construction and Conversion Department at the DEME Group, comments: “The design of the ‘Bonny River’ is inspired by a drive to continuously innovate from an ecological and efficiency perspective. As such, DEME continues to be at the forefront of the industry and significantly reduces the environmental impact of its operations. SCHOTTEL’s propulsion solutions fit in this strategy.”

SCHOTTEL SCPs and STTs for maximum manoeuvrability
“Bonny River” is driven by two SCHOTTEL Controllable Pitch Propellers type SCP 129 4-XG with an input power of 8,000 kW each and a propeller diameter of 4.5 m. It reaches a speed of approximately 16 knots. Beyond this, maximum manoeuvrability and propulsion efficiency are provided by tunnel thrusters – two STT 3 FP (750 kW each) and one STT 5 FP (1,500 kW) – which can be demounted from above.

Together with SCHOTTEL’s control partner NORIS and IHC Systems, a complete power management system was developed. This controls the mechanically driven dredging pump, PTOs and the propellers without overloading the dual-fuel engines.

About “Bonny River”
The new dredger combines various functions and has a large transport capacity – all at limited depth. The vessel is highly suitable for coastal protection assignments, even in regions with shallow beaches. “Bonny River”, part of DEME’s multi-year fleet investment programme, is currently being mobilized in Flushing (Vlissingen), Netherlands, for its first assignments.