Below is an interactive map of the various points on the Hillsborough showing the mile points going south and north from the TRC dock at Jean Street Shipyard.  You can drag and drop the map as well as zoom in.  Below are the one way distances to various landmarks down river from the dock:

Point km Miles
Hillsborough Bridge 2.1 1.3
Tampa Catholic 3.6 2.2
MLK Bridge 4.1 2.5
Columbus Bridge 6.2 3.8
Rick's 6.6 4.1
Boulevard Bridge 7.2 4.5
Tampa River Center 8.3 5.1