Resource that lists new interstate mileage?

[chays]

I'm looking for some sort of resource that lists new interstate mileage as they come into being.
I know that Wikipedia has a great page for interstates and auxiliary interstates, and the tables can be sorted by year, but what I'm looking for is when existing interstates get additional miles.

As an example, I-69 (and I-69E, C, and W) is an active project with miles being added to the interstate system. Is there some sort of site that actually provides information as new miles come on-board?