If a large rock, or some other naturally occurring event, falls onto a given RR main line, is there any technology, or warning system, available to alert passing trains? If it’s a lightly used line, and presumably there are no block lights, how long will it take for the relevant individuals to be alerted? Are there lines running through geographically dangerous locations (like UP’s Columbia River Gorge Subdivision) that have some additional apparatus for detecting this kind of material? I’ve heard that there are some CTC block light systems that will automatically go red if said debris falls onto the line. I’m just curious how that would all work technologically. For instance, haven’t there been cases where livestock or other animals have actually sat on the RRs for certain amounts of time?
They have slide fences that may be connected to the block signals or a stand alone signal. UP has them in the Feather River Canyon, Along the Klamath Lake on the ex SP, east of Troutdale in the Columbia river george and I believe I saw some on the ex SP Cascade crossing above Oakridge. They are a series of wires strung back and forth along the side of the track like a fence. Sometimes breaking the wire stops current flow through it causeing the warning signal(s) to light and sometimes tension on the wire triggers the signal. Animals that don’t clear out usually become hamburger and trees across the track become kindeling and if big enough can cause a derailment, same with rocks. Could you imagine zipping along the BNSF Falbrook sub in the thick forrest at 50 Mph and rounding a curve to find a big tree across the tracks? It happens often up there. But in all the time I lived up there (4-5 years) I never heard of a derailment from hitting a tree though.
Thanks again, Chad!! For any Aussie fans (or SE RR fans out there), have there been any recorded incidents of water buffalo, saltwater crocodiles, or Mississippi alligators blocking RR lines in the US or, say, Queensland, the Northern Territory, or Western Australia? (Yes, I’m a crocophobiac…)[8)]
I heard that an Aussie croc actually tried to eat an outboard boat motor once, and there’ve been recent anecdotes of salties actually moseying into small towns along the northern Australian Gold Coast, and some around or near Cancun, so yes, I’m fishing for stories…
In the case of CP in the Kicking Horse Pass, there are slide fences as mentioned. When a rockslide breaks the wires, I think the signals switch to red, and there’s also a light or something that alerts the RTC for the sub. I think this is common all over the CP where there are a lot of unstable cliffs.
There was a picture in TRAINS a few years ago that showed a boulder on one of Conrail’s lines that ran by a river. They only reason there was not a derailment was because the brakeman/ engineer saw it in time to stop.
BNSF, in the pacific northwest (Colfax, WA for one) has had geotechs (Shannon & Wilson) setting strain gauges in vertical slope piling that are connected to the CTC plant, to keep rain soaked hilsides from moving unanounced.
The Adirondack has that problem all the time - it’s not usually rocks, though, it’s trees falling on the ROW due to natural causes (although we did have a guy drop one across the tracks right in front of us once). Generally speaking, the locomotive will win the encounter if it comes to a collision, but we usually try to get stopped first and cut, move, or otherwise get the obstruction far enough off the ROW for us to pass.
Our MOW folks will patrol the tracks if there is a high likelyhood of trees down, like after a windstorm.