33 CFR § 117.337 - Trout River.
The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows:
(a) The bridge is not tended.
(b) The draw is normally in the fully open position, displaying green lights to indicate that vessels may pass.
(c) As a train approaches, provided the scanners do not detect a vessel under the draw, the lights change to flashing red and a horn continuously sounds while the draw closes. The draw remains closed until the train passes.
(d) After the train clears the bridge, the lights continue to flash red and the horn again continuously sounds while the draw opens, until the draw is fully open and the lights return to green.