Fiber maps of Minnesota

I work for a company that hosts services out of a datacenter in
Minnesota. We're starting to plan the location of our next-generation
data center, and we want to know if there is a place where we can get
maps of local fiber-optic routes? We would like to see maps from
several providers so we can ensure redundant connectivity.

Does anyone have any hints as to how I can obtain such information?

- Erik Amundson