Pipeline?

My boyfriend and I, rather than taking our usual Sunday morning walk along the remains of the Grantham Canal, walked up the hill and turned right opposite Tollerton Park. We walked down the track and through the fields and saw several of those pipeline markers. When we got home I googled the details and learned it is an oil pipeline. It looks like it comes from the storage depot at Colwick but we can’t figure out where it goes to. But the thing is, the pipeline seems to run right through the area where developers want to build 4,000 homes, 2 schools and a health centre. So my question is, why is the pipeline there? What does it do? Is it used or unused? Where does it go? And why is it still there if it’s unused?