What is a flooded ROW checked for prior to use?

[dldance]

thanks BaltACD for the FRA stuff -- however, it appears that even the FRA did not consider a flood of this magnitude.

this cleanup will be enormous.

dd

[BaltACD]

Following is FRA issued guide lines for inspection:

TRAINING GUIDELINES FOR SPECIAL INSPECTION AT

DRAINAGE STRUCTURES AFTER FLOODS AND STORMS





Introduction



As a result of the recent weather related derailments on railroads, FRA has issued a safety advisory 97-1 which requires that a special inspection of track must be made after flood, severe storm or other weather related occurrences which might have damaged the track. These training guidelines have been developed to help track inspectors detect erosion or scour at bridges and culverts during their track inspections after such occurrences. They are intended to provide criteria for inspectors to look for telltale signs and unusual conditions at a bridge or culvert that will indicate a scour or erosion problem.





FRA Advisory 97-1 dated September 4, 1997



FRA Safety Advisory 97-1 recommends safety practices to reduce the risk of train derailments caused by damage to tracks, roadbed and bridges resulting from the uncontrolled flows of water and similar weather related problems. Some of the key points of the advisory are as follows:



· Identify vulnerable bridges and culverts

· Compile a list of vulnerable bridges and culverts and make the list available to all inspectors.

· Conduct a training program for inspectors and provide initial briefing on the contents of this advisory.

· Conduct refresher training courses and update list of vulnerable bridges annually.



A copy of the FRA Safety Advisory is included herewith for information.





Initial Listing of Vulnerable Structures by Subdivision



A list of vulnerable bridges and culverts by subdivision has been prepared and is available to all inspectors. A copy of the list is attached. This list will be updated as necessary and will be maintained in the computer system to be accessible to all inspectors. Contact Director of Bridge Design to report changes to structures or in field conditions that warrant revision of the list.











Vulnerable Structures





The following factors are considered in determining the vulnerability of structures:



· Structures with past history of erosion and/or wash outs are likely to have problems during a severe storm and resulting high water flow.



· Streams having channel configurations in which the water course makes a sharp turn or has a sudden slope change near the structure are at higher risk of scour and wash out during heavy storms.



· Structures having inadequate waterway opening are susceptible to scour due to increased velocity of water and high headwater.



· Extensive urban development upstream from the structure increases run off to the structure and will make the structure vulnerable to scour and wash out.



· Excessive silting reduces the waterway area and can increase the depth of water against the embankment and the risk of scour.



· Drift build up at bridges or culverts can reduce the structure’s ability to carry water. Large pieces of drift or significant accumulations of drift will increase turbulence and increase velocity of flow creating scouring conditions. As a rough guideline, if drift occupies 25% or more of the waterway opening it can threaten the structure and the track.



· Bridge piers, bents and abutments with existing scour are vulnerable to further damage by heavy water flow during storms. Excessive scouring around bents, piers and abutments can lead to bridge failure.



· Framed bents and piers supported on timber mat foundations, commonly referred to as mud sills, are more susceptible to scour due to the flowing water and damage from drift accumulation.





Water Flow in Culverts





Culverts are relatively small structures that carry storm water runoff under the tracks. Typically, culverts are concrete or stone boxes, concrete or stone arches, concrete pipes, steel pipes or rail-top culverts.









· Flow through a culvert during storm events is characterized by a rise in water level on the culvert’s upstream side (inlet). The water level will commonly submerge the culvert.



· The culvert should have adequate waterway opening to carry peak flow. A peak flow or design flood is the amount of water a culvert can pass safely without damage. These floods can be referred to as 50 or 100 year storms, meaning on average peak flow will occur once every 50 or 100 years. Sometimes these floods can occur within a few years of each other even though it is not very common.



· Track ties above the culverts are marked with paint to show the location of the culvert. This will be especially helpful when water level is high and culvert is submerged.



What to look for when water is up



· During storms the water level at the inlet of a culvert will rise. The water level should not be less than 2’ below the ballast line. If the water level is higher than this the culvert and track are vulnerable to wash out.



· Cracks in the fill slope indicate the end of the culvert may have settled due to scour or a landslide is developing in the fill above the culvert.



· Erosion behind the headwalls or wingwalls can be a sign of potential problem affecting the stability of the fill slope and track structure.



· During peak flows a “scour hole” may develop at the outlet end of a culvert. (See attached sketch showing the typical scour locations). These holes are only visible after the water level has dropped. Formation of a “stationary wave” near the outlet is a sign of scour below the water.



· The outlet fill slope should be observed carefully for saturated fill conditions. Water seeping through the embankment is a sign of a weakening of roadbed. This condition will normally develop near the bottom of the slope or adjacent to the culvert structure. The seeping water will wash away fill material causing erosion that will threaten the track stability.



· High-water mark and drift accumulation on the surrounding trees and vegetation gives an indication if water is receding. After water has receded, the culvert shall be inspected for drift and debris accumulation.











Water Flow Through Bridges





Bridges over streams generally have timber, concrete or steel superstructures, supported by pile bents, masonry piers and abutments. Bridges are designed to provide adequate waterway area to carry peak flow under the bridge. When the bridge is minimal width compared to the natural channel, it constricts the flow raising the water level and increasing velocity of the flow.





· The bents, piers and abutments are obstructions to the flow and can create turbulence and increase the chance that scouring will occur around these bridge members (See attached sketch showing typical scour locations). At pile bents, the scour reduces the soil support and can result in settlement of foundation.



· When drift builds up against bents or piers, it acts like a dam raising the water level. It restricts the flow, creates turbulence and increases flow velocity. Scouring is more likely to take place under these circumstances. During heavy storms, the water pressure against the drift will have to be resisted by the bent or pier it rests against. Combination of reduced capacity due to scour and excessive pressure may cause failure of a bent or a pier.



· Track geometry across the bridge shall be monitored carefully. Changes in the alignment, profile and cross section can indicate settlement problems.



· Roadbed embankment at the approach to a bridge are susceptible to wash out during high floods and shall be monitored. The fill slopes shall be observed carefully for saturated soil condition and water seeping through the fill. The seeping water will wash away fill material a causing erosion that will threaten the track stability.



· Stream bed and slopes of the channel will scour under normal and high flows. A change in alignment or noticeable lowering of channel water over time can be a sign of future problem.



















What to look for when water is up





· Water level during peak flows should not reach the bottom of bridge superstructure (bottom of beams, girders or trusses). If the flood waters rise above this elevation, the bridge is vulnerable and traffic shall not be allowed on the bridge except under the direction of bridge supervision.



· Track geometry on the bridge and at approaches shall be observed carefully. Any changes in alignment, profile or cross section in the track may indicate a problem with the bridge or track structure.



· Check embankment slopes behind wingwalls to see any sign of landslide or erosion. If cracks are observed at top of embankments, it is indicative of a landslide developing due to the wash out at the toe of fill.



· Check for drift build up. If drift has built up against a pile bent or pier, observe if any movement appears to have taken place. If drift occupies 25% or more of the waterway area under the bridge, it can threaten the structure. Considerations should be given to remove the drift.







--------------------------------------------------------------------------------

[dldance]

I recall see a section of track near Rexburg ID after the Teton dam broke. The rails and ties looked fine on the water, but after the water went down, there was no roadbed under the track! Roadbed is obvious - but that is what got me thinking about other damage to look for.

dd

[jchnhtfd]

Tulyar -- which is why I said that you have to check the bridge piers and abutments -- for which you just have to wait a bit!

I got to musing, though, on how the railroadmen 'way back when' got away with some things (like running through flooded track) that we wouldn't do now... and one thing hit me: the engines were a lot lighter, and the axle loadings were a lot less. A big 4-4-0 might have had 30 tons per axle, and often half that. That puts a lot less stress on the track structure and fill than a modern engine, which could easily be twice that. So if the fill is weakened by being saturated, a light engine might make it while a heavy modern engine would just collapse the fill...

[Tulyar15]

In Britain, after an accident that happened during a flood, the procedure for checking bridges has been revised. About 20 years ago a 2 car passenger train on the Heart of Wales line fell into a river in flood when the bridge it was on collapsed. Fortunately the passengers got out alive but in ensuring that they did spo the engineer paid the ultimate price. Afterwards it was found that during the flood the normal flow of the river had altered and it had eroded parts of the bride foundations that it did not normally come anywhere near. As a result revised procedures were drawn up.

[mudchicken]

QUOTE: Originally posted by Mark300

I've seen old photos of steam locomotives in flood waters actually (according to the author/photographer) operating and pushing/pulling cars.

I know the distance between water on the rails and the motors in the wheels on todays diesel-electrics are very critical to their operation.

Do the rails have to be completely visible? Or are there exceptions like within an industrial facility or yard where the rails and surrounds are paved? (Debris not withstanding)

In light of the Katrina disaster down south, this is a worthwhile thread.

Just wondering.

Mark

Dependent on the individual railroad's rulebook, the water can be up to 5 inches above top of rail. When it got close to 4 inches, our old railroad had the mechanical supervisor ride the slow moving train over the high water and cut out the traction motor blowers (to keep water out of the traction motor case. With the post Dash-2 newer engines, I don't know if this can be done any more. Maybe Randy Stahl can enlighten us.

Jchnhtfd has it about right on the reactions to running submerged track. In addition I guarantee the roadmaster and the motor track inspector are patrolling the track before and after the train passes and they watch the train thru the water looking for excess deflections. Any switch under water is spiked and clamped shut until it emerges again and can be maintained....and if it is running water, you're working like mad to keep the upstream side clear of debris.

(The railroads are circling the wagons now and have lined up consultants (surveyors and engineers) to thow at problems after the initial crisis is addressed. A lot of the older railroaders remember when railroads could be self-sufficent and throw resources at problems like this - no longer even remotely a possibility in today's dumbsized world... "Lean & Mean" now starts looking like starving and stupid....)

[Anonymous]

QUOTE: Originally posted by jchnhtfd

Mark -- sort of depends on how gutsy the engineer is! If I couldn't see the ties and ballast, I'd walk... but then, I'm kind of conservative.

The traction motors have astonishingly little clearance, and just a few inches -- two or three -- and they will be in the water. Even with less, they will be being splashed, and traction motors = high voltage elextricity. And electricity and water just don't mix.

Steam engines don't have this problem, of course. But still, in terms of safe operation, you'd never do it nowadays. But then, there are a lot of things we don't do now which seemed perfectly all right 'way back when'!

Our rule is one inch over the rail. But i will tell you what i would do. I would have the conductor walk about fifty yards infront of me to make sure the track is still there. if he dissapears i know to stop, if he does not disappear i will keep on going at a walking pace!!

[Anonymous]

AND... Here's some pics of damage in New Orleans specific to CSX.

http://www.utu.org/worksite/detail_news.cfm?ArticleID=23308

[Anonymous]

I have access to look at other dispatching territories from my screen at work and I can tell you that the entire coastal CSX line from New Orleans east to Mobile is completely out of service. The entire track is blocked off with 707 Authorities and many of the control points show no power. I have even heard from some of the maintenance managers that a big section of the track bed is just washed away, so to answer the question the RR's down there have a LOT of work to do before any trains will be running on the track and of course MC expound on that quite a bit.

[Mark300]

QUOTE: Originally posted by jchnhtfd

Mark -- sort of depends on how gutsy the engineer is! If I couldn't see the ties and ballast, I'd walk... but then, I'm kind of conservative.

The traction motors have astonishingly little clearance, and just a few inches -- two or three -- and they will be in the water. Even with less, they will be being splashed, and traction motors = high voltage elextricity. And electricity and water just don't mix.

Steam engines don't have this problem, of course. But still, in terms of safe operation, you'd never do it nowadays. But then, there are a lot of things we don't do now which seemed perfectly all right 'way back when'!

Jamie.....

Thanks for the insight!


Mark

[jchnhtfd]

Mark -- sort of depends on how gutsy the engineer is! If I couldn't see the ties and ballast, I'd walk... but then, I'm kind of conservative.

The traction motors have astonishingly little clearance, and just a few inches -- two or three -- and they will be in the water. Even with less, they will be being splashed, and traction motors = high voltage elextricity. And electricity and water just don't mix.

Steam engines don't have this problem, of course. But still, in terms of safe operation, you'd never do it nowadays. But then, there are a lot of things we don't do now which seemed perfectly all right 'way back when'!

[Mark300]

I've seen old photos of steam locomotives in flood waters actually (according to the author/photographer) operating and pushing/pulling cars.

I know the distance between water on the rails and the motors in the wheels on todays diesel-electrics are very critical to their operation.

Do the rails have to be completely visible? Or are there exceptions like within an industrial facility or yard where the rails and surrounds are paved? (Debris not withstanding)

In light of the Katrina disaster down south, this is a worthwhile thread.

Just wondering.

Mark

[jchnhtfd]

dd -- I'll bet MC checks in on this when he wakes up, but...

ballast: do you still have full cribs? Or have you lost some or all of the ballast?
fill: is it still in decent conditiion, or do you have washouts or saturated places which have lost their strength?
culverts: are they clear, or have they silted in?
bridges: are they in decent shape? Bearings, abutments and piers (undercutting particularly)? Anything hit them? Condition of bridge overall...
track: are the ties still properly held by the ballast? Cross levels, alignment (horizontal and vertical)? condition of any joints?
special work (switches, diamonds): clean out the frogs and points, check swtich machines, check shunts (if used), check all fastenings, make sure they work, lube everything in sight...
signals: if your wiring got wet, you have to check every signal and relay for correct operation, or run dark until you can.

As well as the more obvious clearing of debris...

I'm sure I've left something out.

[dldance]

I can imagine that a flood causes all kinds of problems. What are the most common?

dd