Offshore Natural Gas Pipelines

Enterprise owns or has an interest in approximately 1,400 miles of offshore natural gas pipelines strategically located to serve production areas including some of the most active drilling and development regions in the northern Gulf of Mexico, Texas, Louisiana, Mississippi and Alabama, as well as approximately 1,000 miles of offshore crude oil pipelines and six offshore hub platforms.

Our offshore Gulf of Mexico pipelines provide for the gathering and transportation of natural gas or crude oil. Typically, these systems receive natural gas from production facilities and other pipelines through system interconnects and transport natural gas to various downstream pipelines, including major interstate transportation pipelines that access multiple markets in the eastern half of the United States. In general, these pipelines generate revenue based on transportation fees charged per unit of volume (typically in MMBtus of natural gas or per barrel of crude oil) gathered or transported multiplied by the volume delivered. These agreements are often long-term in nature, often involving life-of-reserve commitments with firm and interruptible fees.

Our offshore platforms are critical components of the energy-related infrastructure in the Gulf of Mexico and support drilling and producing operatons, playing a key role in the development of offshore crude oil and natural gas reserves. Revenues from our offshore platform services generally consist of demand fees and commodity charges. Demand fees are charged to a customer regardless of the volume the customer actually delivers to the platform. Revenues from commodity charges are based on a fixed-fee per unit of volume delivered to the platform (generally per MMcf of natural gas or per barrel of crude oil) multiplied by the total volume of each product delivered.

Offshore Natural Gas Pipelines
Facility	Ownership Interest	Miles	Approximate Net Capacity (MMcf/d)	Function
High Island Offshore System (HIOS) (1)	100%	291	1,335	FERC-regulated offshore natural gas transmission system that transports production from fields in the Western Gulf of Mexico to numerous downstream pipelines off the coast of Louisiana including ANR and Tennessee Gas Pipeline, UTOS and Stingray.
Viosca Knoll Gathering System	100%	137	600	Natural gas gathering system located off the coast of Louisiana that gathers production into several major interstate pipelines including Tennessee Gas, Columbia Gulf, Southern Natural, Transco, Dauphin Island and Destin.
Independence Trail	100%	134	1,000	Offshore natural gas pipeline that transports natural gas from the Independence Hub platform to Tennessee Gas Pipeline in the West Delta area of the Gulf of Mexico.
Green Canyon Laterals	Various (2)	73	446	A group of 11 pipeline laterals (which are extensions of natural gas pipelines) located in the Gulf of Mexico offshore Texas and Louisiana, which deliver to numerous downstream pipelines including the HIOS system.
Phoenix Gathering System	100%	77	450	Offshore natural gas pipeline that connects the Red Hawk platform in the Garden Banks area of the Gulf of Mexico to the ANR pipeline system.
Falcon Natural Gas Pipeline	100%	14	400	Natural gas gathering line located off the Texas coast that delivers gas processed on the Falcon Nest platform into the Central Texas Gathering System.
Anaconda Gathering System	100%	137	300	Offshore natural gas pipeline that connects the Marco Polo and Typhoon platforms in the Green Canyon area of the Gulf of Mexico to the ANR pipeline system.
Manta Ray Offshore Gathering System (3)	25.7%	250	206	Unregulated natural gas gathering lines that transports natural gas from producing fields located in Green Canyon, Southern Green Canyon, Ship Shoal, South Timbalier and Ewing Bank areas to numerous downstream pipelines.
Nautilus Pipeline System (3)	25.7%	101	154	FERC-regulated natural gas pipeline and related facilities that connect our Manta Ray Offshore Gathering System to our Neptune natural gas processing plant located in south Louisiana.
VESCO Gathering System(4)	13.1%	158	65	Regulated natural gas gathering line located in south Louisiana that is an integral part of the natural gas processing operations of VESCO.
Nemo Pipeline (5)	33.9%	24	102	Offshore Louisiana natural gas gathering pipeline that transports natural gas from Green Canyon developments to our Manta Ray Offshore Gathering System.