Rather than laying two sets of tracks parallel to eachother all over the city, an expensive task, trolley companys would lay one set, and every so often split the rails into two sets occasionally, so when two trolleys going in opposite directions came up each other, one would stop, and allow the other to pass on the other half of the split. There was such a split on or near the trestle.
On April 28th, Car No. 52 of the Mt. Tabor Line (operated by the City & Suburban Railway Company) was crossing said trestle too fast, and when the Pullman-model car hit the switch, she jumped off the track, and crashed through the trestle's railing and into the waiting slough, turning upside down in the process.
Three passengers were killed, and another died later of injuries sustained in the wreck.