I found an article about The West Trenton RR Bridge which was published in ENGINEERING NEWS Volume 69 Number 22 May 29, 1913:
This description suggests several things to me:
1) Travelling East from Yardley there is a bridge over South Main Street adjacent to the station.
This is followed by another bridge over the Delaware Canal,
which leads into the approach to the West Trenton RR bridge,
which is an earthen embankment.
2) I had thought that the original track pans were located West of the station. This idea was based on known water supply
( Silver Lake Dam and Oxford Road Pump Station - This was known as White's Lake when the dam was built in the 1870s )
and the belief that locating track pans on the elevated embankment East of the station would leave them too exposed to
wind, weather, and a greater likelihood of freezing. This description would indicate a location on the bridge approach
( how else could water splash onto the bridge members ? )