Offshore Natural Gas Pipelines

Enterprise owns or has an interest in approximately 1,555 miles of offshore natural gas pipelines that provide gathering and transmission services for natural gas developments located in the Gulf of Mexico, primarily offshore Louisiana and Texas. These systems receive natural gas from production facilities and other pipelines through system interconnects and transport the natural gas to our processing plants and pipelines, as well as other downstream natural gas processing plants and pipelines that serve markets throughout 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) transported. These agreements tend to be long-term in nature, often involving life-of-reserve commitments with firm and interruptible fees. Our offshore natural gas pipeline systems do not take title to the natural gas volumes they transport; rather, the shipper retains title and the associated commodity price risk.

During 2004 we announced the construction of the Constitution and Independence Trail natural gas pipelines. The Constitution Oil Pipeline is a 30-mile natural gas pipeline with a net capacity of approximately 200 MMcf/d and was completed in late 2005. This pipeline serves the Constitution and Ticonderoga fields located in the central Gulf of Mexico. Initial throughput volumes were received during the first quarter of 2006. The Constitution Oil Pipeline connects with our Cameron Highway Oil Pipeline and Poseidon Oil Pipeline System at a pipeline junction platform.

Independence Trail is a 134-mile, 24-inch diameter natural gas pipeline located on the floor of the Gulf of Mexico that connects to the semi-submersible Independence Hub platform to the West Delta 68 platform near the coast of Louisiana. From the West Delta platform, natural gas is transported to onshore markets in Louisiana via Tennessee Gas Pipeline. In July 2007, our Independence Hub platform and Independence Trail received first production from deepwater production wells connected to the Independence Hub platform. Independence Trail has the capacity to handle 1,000 MMcf/d of natural gas.

Facility	Ownership Interest	Miles	Operator	Function
Offshore Natural Gas Pipelines
Manta Ray Pipeline System	25.7%	250	Shell	Unregulated natural gas gathering lines primarily located on the outer continental shelf offshore Louisiana.
Nautilus Pipeline System	25.7%	101	Shell	FERC-regulated natural gas pipeline and related facilities extending from points offshore Louisiana to connecting pipelines near Garden City and Neptune gas processing facilities.
Nemo Gathering System	33.9%	24	Shell	Offshore Louisiana natural gas gathering pipeline that connects certain Shell offshore platform assets to Manta Ray.
Viosca Knoll Gathering System	100%	172	Enterprise	Natural gas gathering system located off the coast of Louisiana that gathers production into several major interstate pipelines including Tennessee, Columbia Gulf, Southern Natural, Transco and Destin.
High Island Offshore System	100%	291	Enterprise	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.
VESCO Gathering System	13.1%	260		Natural gas gathering line located in south Louisiana.
Falcon Gas Pipeline	100%	14	Enterprise	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 ⁽¹⁾	100%	137	Enterprise	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.
Phoenix Gathering System	100%	77	Enterprise	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.
Green Canyon Laterals	0% - 100%	95	Various	A group of 28 laterals that 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.
Independence Trail	100%	134	Enterprise	Offshore natural gas pipeline to be constructed that will connect the Enterprise-owned Independence Hub platform in Mississippi Canyon Block 920 to Tennessee Gas Pipeline in the West Delta area of the Gulf of Mexico.

⁽¹⁾ Data shown for the Anaconda Gathering System includes the 30-mile Constitution natural gas pipeline.