The expansion, which is expected to be available in the first quarter 2011, involves an optimization of existing facilities and services with limited capital investment.

The North Dakota system mainline capacity between Minot and Clearbrook was recently expanded by 51,500bpd to 161,500bpd through the Phase VI expansion.

The company said that the reconfigured operating mode will have an overall capacity of 185,000bpd.

Enbridge Energy Partners owns and operates a diversified portfolio of crude oil and natural gas transportation systems in the US.