Shell has achieved yet another milestone in the Ursa/Princess Waterflood project. First injection of water occurred on July 3, 2008, and is planned to continue for the next 30 years. With a listed volume enhancement capacity of 30,000 boe/d, the waterflood is expected to extend the life of the field by 10 years.

"The Ursa/Princess Waterflood project represents a significant investment by Shell and the other interest owners in one of the most prolific areas in the Gulf of Mexico — the Ursa-Mars basin. Ursa-Princess has produced nearly 400 million barrels of oil equivalent to date and we believe potential exists for continued development of material oil and natural gas within this basin," said Russ Ford, vice president technical, Shell Americas.

The Ursa/Princess Waterflood is one of the largest construction projects on an existing platform in the Gulf of Mexico. This presented challenges of very high activity levels and simultaneous construction, commissioning, maintenance and well servicing activities, while performing production operations on a large facility located 100 miles offshore. The relentless focus on hazard management and emphasis on reducing risk exposure resulted in strong safety performance over the entire project.

Waterflood is a method of secondary recovery in which water is injected into the reservoir formation to displace additional oil. The water from injection wells re-pressurizes the formation and physically sweeps the displaced oil to adjacent production wells. The Ursa/Princess Waterflood topsides injection system injects filtered and treated sea water via two separate flowlines to three subsea sites — one to an existing well site northwest of the Ursa tension-leg platform (TLP), one to an existing well site southeast of the Ursa TLP and one to a new well site northeast of the Ursa TLP. Producing wells will include three Princess subsea wells and as many as six Ursa TLP wells.

Ursa is located in 3,800 ft of water and encompasses Mississippi Canyon Blocks 808, 809, 810, 852, 853 and 854.

Princess is located in Mississippi Canyon Blocks 765 and 766, in approximately 3,650 ft of water.

Shell is operator of this project with 45.39%; BP Exploration & Production Inc. has 22.69%; Exxon Mobil Corporation and ConocoPhillips Company each have 15.96%.