Crude oil will begin pumping to Southeast Texas refineries from Cushing, Oklahoma beginning Wednesday morning.
Transcanada representatives tell 12News federal regulators have given the company the all clear to start the production.
Early testing found no leaks or issues with the pipeline.
The Gulf Coast project can handle 700,000 barrels of crude a day.
Transcanada says it takes about three days for the crude oil to reach Southeast Texas from Cushing.
The company says it will brief the media when the start up begins Wednesday.
The Obama Administration has yet to approve the Keystone XL pipeline from Canada to Southeast Texas.
Refineries along the Gulf Coast have spent billions of dollars on equipment to efficiently process the heavy Canadian crude oil.