#1 grab your crank arms and rock them back and forth, tword and away from the center of the bike; if there is any movement of the spindle in the crank, the BB is toast. If not try this test: put you front wheel against a wall with the crank arms parallel to the ground and push down on the forward pointing crank to see if you can reproduce the creak. If so, it may need another BB or nothing more than to be removed, cleaned up and re-installed; this time use Teflon tape. Bottom bracket threads can wick in water which takes crud with it, causing a creak.