Zephyr Rail (ZUI) provided aerial mapping and structural engineering services to support Fillmore & Western Railway’s bridge rehabilitation effort. The existing bridge at milepost (MP) 416.32 is an old ballast-deck timber trestle structure, which will be replaced with an open-deck structure with steel stringers. To survey the site’s existing conditions, ZUI utilized its state-of-the-art unmanned aerial vehicles (UAVs) to provide aerial mapping of the existing bridge and its approaches. Additionally, ZUI prepared the permitting applications to gain approval from the California Department of Fish and Wildlife and the U.S. Army Corps of Engineers for this work. ZUI personnel also prepared structural drawings to support the design and construction of this bridge replacement.