Well, Fixxer called the LCRA and they just emailed him some hi-res images of the dam and WP. These are *very* detailed. You'll want to crop the area you dive before trying to print it on 8.5x11.
http://media3.uploadjar.com/file.php?file=uploads/travis_map.zip
http://media3.uploadjar.com/file.php?file=uploads/travis_map.zip