Washaway

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This article is about a kind of landslide. For the place in Cornwall, see
Washaway, Cornwall
.
Flood damage to rail track in Queensland, Australia, showing complete washaway leaving rails suspended

A washaway is a particular kind of

embankments and bridges
. They are thus a hazard to railways and road traffic.

The biggest danger with washaways is that they may be difficult to spot in time to stop short of the point where one falls over the edge and/or into the water where one may drown.

Repairs

An embankment that is washed away can be repaired or restored by replacing the washed away earth, which is necessarily large because embankments have a gentle slope.

A quicker method is to replace the washed out earth with a criss-cross structure of timber steepers called a

pigsty which is only slightly wider than the track itself. The pigsty has alternating layers of transverse and longitudinal layers of these sleepers, which contains a lot of air which saves weight.[1][2]
Steel and concrete sleepers are not necessarily suitable for this purpose as they are either not square or fragile.

The sleepers in the pigsty can be reused when the washaway is fully repaired. Rails can substitute for the sleepers. The hollow space inside the pigsty should be able to act as a culvert.[3]

Warning devices

A mechanical railway signal that is normally "green" can be put to "red" if a link in the pulling wire is disengaged by a slump of the earth beneath.

An electrical railway signal that is normally green can be put to red if a contact is opened circuited by a slump of the earth beneath. One side of contact might be attached to the

1993 Big Bayou Canot train wreck
.

Accidents

Railway accidents involving bridge washaways include:

  • United States 27 September 1923 – near Glenrock, Wyoming - a bridge over Coal Creek was washed away and a passenger train derailed, killing 30 of the train's 66 passengers.
  • New Zealand 24 December 1953 - Tangiwai disaster - lahar caused bridge washaway; train thrown into river; 151 killed.
  • Australia 1974 - Crystal Brook, South Australia - train thrown into river after washaway collapses bridge.
  • Kenya 1993 - 114 perished in a passenger train that plunged into a river after floods washaway a bridge at Ngai Ndethya.
  • Veligonda train disaster
    - 114 killed
  • Italy November 2011 - Feroleto-Marcellinara, Italy [4]

Cause unclear

See also

References

  1. ^ "A Washaway on the Northampton Railway". Sunday Times (Perth, WA : 1902 - 1954). Perth, WA: National Library of Australia. 12 July 1925. p. 13. Retrieved 9 September 2011.
  2. ^ "THE WASHAWAYS". Geraldton Guardian (WA : 1906 - 1928). WA: National Library of Australia. 14 March 1925. p. 4. Retrieved 9 September 2011.
  3. ^ "WILUNA FOOD SHORTAGE". Western Mail (Perth, WA : 1885 - 1954). Perth, WA: National Library of Australia. 5 April 1934. p. 18. Retrieved 9 September 2011.
  4. ^ Today's Railway Europe 213, pg 55
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