RedactedNarrative: Operating vessel with sails down and under motor power, down bound on the Kinnickinnic River approaching the rail bridge and the Kinnickinnic River Bascule Bridge. Operator stated that he had called in advance to have the bridge   opened, and had also called the bridge to have it opened at the time of his approach. Operator stated that the bridge was partially open for 1 1/2 to 2 minutes, when he began to pass underneath.  Operator stated that once he was half way underneath, the bridge came down on his mast, causing the described damage and possible injury.  Witness stated that he was on the street, waiting for the bridge to allow traffic, when he observed the bridge open approximately 40 to 45 degrees for approximately 1-2 minutes. Witness stated that once the boat was 1 /2 to 2/3 of the way through, the bridge lowered onto the mast, causing the described damage.  Bridge Operator stated that once his bridge operation was complete, he observed the Bascule bridge begin to open, and retreated to his bridge house. The Bridge Operator stated that he did not see the incident, but heard screaming from the operator of the sailboat, and saw that it had been damaged by what he believed to be the Kinnickinnic River Bascule Bridge .  None of the people the Officer spoke with could recall the color of the bridge lights, and whether they were lit.  After the incident, the Operator motored his boat back to the Horny Goat Marina and tied it off.   The Operator did not advise me of the damage estimate.  Damages were photographed by Forensic Investigator who took 25 photographs.