Here is another drone capable of inspecting bridges with a 4K camera. The Walkera QL900 has a 6-axis motor design and can resist crosswind around the bridge. It comes with a 3-axis gimbal and camera to conduct inspection on hard to reach areas under the bridge.
Walkera QL900 has a camera with a 18x optical zoom lens. It captures 4K videos and 16MP photos. More info is available here.