Difference between revisions of "Gradient profile and mileages"

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==See also==
 
==See also==
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[[Engineer's Line References]]<br>
 
[[Main Page]]
 
[[Main Page]]

Revision as of 21:25, 8 May 2016

The gradient profile of the SVRSevern Valley Railway between Kidderminster and Bridgnorth is shown below. The diagram, which is reproduced from the SVRSevern Valley Railway Visitor Guide Eighth Edition (2001), is based on official GWRGreat Western Railway documents.

SVR Gradient Profile.jpg

Gradients

The profile shows the average gradient in each section (the vertical scale is exaggerated), thus on leaving Kidderminster the line initially goes downhill with a gradient of 1 in 112. ‘L’ indicates level. According to the GWRGreat Western Railway gradient profiles, the steepest gradient on both the orignal Severn Valley Railway and the Loop line did not exceed an average of 1 in 100 in any section.

Gradient posts showing changes in gradient can be seen at the lineside. The design varies, but generally follows the principle of this prominent example near Highley station.

Mileages

The GWRGreat Western Railway generally measured distances to particular locations from London Paddington via the most direct GWRGreat Western Railway route (the exact zero point being the Paddington Suburban Tunnel boundary with the Metropolitan Railway). The mileages to locations on the original OW&WOxford Worcester and Wolverhampton Railway route from Hartlebury via Kidderminster Junction to Kidderminster Station, and on the original Severn Valley Railway from Hartlebury via Bewdley South Junction to Bridgnorth and Shrewsbury, were both measured from Paddington via Didcot and Worcester. Distances from London to principal stations in miles and chainsAs a unit of measurement, 22 yards or 1/80th of a mile were as follows (one chainAs a unit of measurement, 22 yards or 1/80th of a mile is equal to 22 yards or 1/80th of a mile):

Location Distance
Hartlebury 131m 68ch
Kidderminster 135m 46ch
Bewdley 137m 28ch
Bridgnorth 149m 74 ch
Shrewsbury (Severn Valley Junction) 171m 59ch

Locations on the Loop between Kidderminster and Bewdley were measured from Kidderminster. The main line station at Kidderminster was a little over 135½ miles from London as shown above (the SVRSevern Valley Railway’s Kidderminster station has been placed a little closer, with a re-constructed 135½ mile post being sited outside Kidderminster Railway Museum. Leaving Kidderminster, the mileage initially decreases (milepost 135¼ being near the Diesel Depot) but then increases again as the loop turns away from London. This accounts for the change in mileage at Bewdley South Junction in the profile above, which is 138 miles 21 chainsAs a unit of measurement, 22 yards or 1/80th of a mile via Kidderminster but only 137 miles 12 chainsAs a unit of measurement, 22 yards or 1/80th of a mile direct via Hartlebury.

Mileage posts showing the distance from London Paddington, as measured above, can be seen at the lineside. In the second example shown, the distance just south of Arley Station is 140¾ miles (the vertical bars below the number show the number of quarter miles). One mileage post is situated at the foot of Highley Signal Box, showing that it is exactly 143¼ miles from Paddington.

The locations of the principal mile posts were often shown on early Ordnance Survey maps, such as this example from 1903 showing the presence of mileposts (MP) at Kidderminster Junction on both branches of the junction.

See also

Engineer's Line References
Main Page