Mardi Gras Transportation System Overview
Authors: Marshall Robert , McDonald William 
Published: October 2008

This paper presents a technical overview of BP's Mardi Gras transportation system project. The Mardi Gras pipeline system, operated by BP America Inc. and under construction in the Gulf of Mexico, is setting new standards for large diameter, deepwater pipeline design and construction. The project includes new oil and gas pipeline networks in two deepwater areas of the Gulf of Mexico where there is no existing pipeline infrastructure. The pipelines range in size from 16" to 30" in water depths up to 7,300 ft.

Introduction

The $1 billion Mardi Gras transportation system (MGTS) will handle oil and gas from five key deepwater developments which BP operates: Holstein, Mad Dog, and Atlantis in the southeastern Green Canyon area, and Thunder Horse and Na Kika in the southeastern Mississippi Canyon (see Figure 1). The Na Kika field began production in November 2003, and the remaining fields will come on stream between late 2004 and mid-2006.

A key feature of the MGTS is the installation of spare wye sled assemblies (WSAs) being installed in deep water to facilitate the later connection of third-party production into the system without lengthy system shutdown. Another feature of the system will be its access to multiple processing facilities and onshore pipelines all along the Gulf Coast.

System Description

The MGTS consists of five separate pipelines, named after New Orleans Mardi Gras parades, owned and operated by BP through its subsidiary Mardi Gras Transportation System Inc. ("Mardi Gras") and its various partners in the deepwater oil and gas developments:

The 450,000-b/d Caesar Oil Pipeline consists of 24-in. laterals and a 28-in. mainline of about 115 miles from the Holstein- Mad Dog-Atlantis area, and is owned by Caesar Oil Pipeline Company, LLC, comprised of Mardi Gras, BHP Billiton Petroleum (Deepwater) Inc. ("BHP"), Shell Pipeline Company LP, and Union Oil Company of California ("Unocal").

The 500-MMcfd Cleopatra Gas Gathering System consists of 16-in. laterals and a 20-in. mainline of about 115 miles from Holstein-Mad Dog-Atlantis area and is owned by CleopatraGas Gathering Company, LLC, comprised of Mardi Gras, BHP, Shell Gas Transmission, LLC, and Unocal.

The 1.2-bcfd Okeanos Gas Gathering System consists of 20- in. laterals and a 24-in. mainline of about 100 miles from the Thunder Horse-Na Kika area and is owned by Okeanos Gas Gathering Company, LLC, comprised of Mardi Gras and Shell Destin, LLC.

The 28 in., 580,000-b/d Proteus Oil Pipeline, about 70 miles from the Thunder Horse semisubmersible platform to a future pump station platform SP89E, is owned by Proteus Oil Pipeline Company, LLC, comprised of Mardi Gras and ExxonMobil Pipeline Company ("ExxonMobil").

The 30-in. Endymion Oil Pipeline, carrying as much as 750,000 b/d 90 miles from the Proteus terminus on South Pass 89E to the Louisiana Offshore Oil Port (LOOP) at Clovelly, La., is owned by Endymion Oil Pipeline Company, LLC, comprised of Mardi Gras and ExxonMobil.

Current Status

About 290 miles of the 485-mile system have been laid. This includes the portion of the Okeanos Gas Gathering System laid by Shell from the Na Kika floating production facility to the shelf platform on Main Pass 260.