This appears to be a Truss bridge of some sort from what the existing piers look like on Google Maps and the Bird's eye View on Bing. Due to the fact that the road approaching either side of it is now private property, it will be hard to reach to get pictures.
More than likely, this bridge got washed away in the Mother's Day Flood of 1957. Satellite Imagery from 1963 shows this bridge as not existing and there is no record of it from any Topo maps going back.
I could speculate that due to the odd nature of where it sits, it may have been on an original alignment of FM1869.
Hopefully, somebody with better tools can find out more information about this bridge.