It is all the capital that they will be spending over the next 8 years. They have pretty firm plans out 5 years. One thing about these pipelines is that they do not spend CAPEX unless there is a real need and before ground is broken most are over subscribed with lon term contracts. Basically they will have higher and higher revenues and earnings going into the future.
They also have 3 other investment vehicles which they control to allow them to tackle many projects. There are two MLPs and and investment company that owns parts of their network. The public owns parts of these MLPs and so they can raise money or sell assets to one of the MLPs and use the proceeds to invest in higher return projects. ENB is more than a company, it is the lead company in an energy empire.