Tangguh Marine Works

Customer: PT Saipem Indonesia

Location: Indonesia

Contract: Design & Build


McConnell Dowell was awarded the design and build contract from PT Saipem Indonesia for the marine works of BP’s LNG expansion project in Tangguh, located in the remote area of Bintuni Bay in West Papua.

PT Saipem Indonesia, is part of the EPC joint venture - Chiyoda-Saipem -Tritati -SAE (CSTS-JV) for the Tangguh Expansion Project consortium.

The marine works comprise of a 1.1 km long trestle, a loading platform and 10 mooring/berthing dolphins. The onshore expansion works will contain a full additional natural gas liquefaction train, including an onshore receiving facility (ORF), an additional Boil of Gas (BOG) recovery, utilities, flares, and all infrastructure to support the facility


Tangguh Expansion Project activities from Engineering to Construction were stopped due to Covid-19 Pandemic around the World. Temporary Demobilization was started from 17 March ‘20 for all management, staff and workers from Tangguh site. As of today, over 90,000 people contracted Covid19 and more than 4,000 people lost their battle with the virus in Indonesia. “New Normal” regulations and standards are being set up for Construction entities by Local government. 

Even though Indonesia is still stricken by high infection rates at the moment, the returning project personnel will be protected by a 2-week compulsory quarantine in a client facility before returning to site.

These issues, coupled with the extremely remote location, environmentally sensitive site, and significant logistical challenges conspired to make this project one of our most challenging to date.


“Best Performing Sub Contractor HSSE Prestigious Award for January 2020 by British Petroleum (BP)”

Scope of Works

McConnell Dowell’s scope of works include:

  • A 1056 m long access Trestle, including decks for the local control room, substation and sea water intake
  • 29 m x 42.5 m Loading Platform for the Jetty with 2 Gangways
  • 4 Breasting Dolphins for the Jetty
  • 6 Mooring Dolphins for the Jetty with 2 Tugboat landings.
  • Provision of the Quick Release Hooks and Docking Assistance System
  • Oil Spill Containment and Catwalks
  • Installation of Loading Arms and Pipe racks supplied by PT Saipem Indonesia
  • Bulk Off Loading Facility (BOF) consisting of a sheet pile retaining wall, anchor walls and concrete copings

Key to Success

PT Saipem Indonesia awarded this contract to McConnell Dowell due to our technical experience and in particular the ability to build the trestle with a crane traveler method to:

  • Minimise offshore work near the existing LNG Loading facility
  • Minimise the disturbance to the mangrove area
  • Eliminate the effect on production during low tide in shallow waters
  • Maximise prefabrication work off-site
  • Minimise manpower on site

Project Gallery