Stairway to Nowhere

They are building a new motorway bypass in Christchurch. I have not worked out what this stairway is for. It's on the top of what I assume will be a flyover. It starts from 3/4 of the way up a manmade clif, and goes to the top. I haven't worked out how to get to it, or why you would bother.

I guffawed out loud when I saw it yesterday, then today my sister suggested she had the perfect blip for me, and took me to see it.

Better large - you get a better idea of the scale of it, and just how stupid it looks.