The Cochran Tunnel, which was recently named an "exceptionally significant" feature of the United State interstate system, could put any future plans to expand I-64 on ice. The designation, one of only three for the entire state of Kentucky, makes it close to impossible to alter the tunnels for an expansion project. I-64 is currently being studied for just such an expansion.
The Louisville interstate system is somewhat strange when it passes through the East End. I-64 and I-71 are still both only 2 lanes in each direction. This alignment creates a pastoral setting for both interstates, but more notably, on I-64. I-64 passes through Cherokee Park and the road is shielded from neighboring buildings by a thick layer of trees, shrubs, and tall natural rock walls. In my opinion, it is one of the most beautiful stretches of urban interstate in the US, as there are only a handful of places with similar settings. (Another road that comes to mind is the parkway between Washington, DC and Baltimore, MD. I do wish I could remember it's designation!)
Due to an increasing population in Eastern Jefferson County and beyond, the state has been trying to identify ways to expand capacity for the future. The state has been studying both I-71 and I-64 for expansions, but has not yet come with any firm plans. Currently, congestion along I-64 is restricted to west of the Cochran Tunnels, and that congestion is only exacerbated by a poorly designed set of interchanges leading to Spaghetti Junction.
To me, the most sensible solution is to expand I-71, for several reasons. First, I-71 leads directly into Oldham County, which is where most of the new suburban growth is taking place. It also has a much smaller interchange with the Watterson and Snyder, which could, and need to be, expanded. Second, I-71 has no interchanges between the Watterson and the Snyder. During an expansion project the state could add new interchanges to I-71, making it easier for residents to use the interstate. Third, the logistics of an I-71 expansion are much more simple - There are no tunnels to work around and the settings, while nice, could have an expanded road without changing the character.
However, due to NIMBY'ism, these projects are slow to take shape and have a lot of political hurdles to cross. Eventually, SOMETHING will have to be expanded, or light rail built, or express bus lines....something! But for now, the traffic is still pretty light, and the East Enders will fight the project until the bitter end.