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[[File:Sterns_20160723.jpg|thumb|300px|right|The telegraph pole at Sterns (summer)]]
[[File:Sterns_20180325.jpg|thumb|300px|right| The telegraph pole at Sterns (spring)]]'''Sterns''' is situated between [[Hampton Loade]] and [[Bridgnorth]] at the foot of [[Eardington Bank]], at approximately [[Gradient profile and mileages|milepost 147]]. It is at a place where the [[River Severn]] approaches close to the railway at almost 90 degrees before turning away southwards towards Bewdley, and is notorious as a maintenance trouble spot due to the ground regularly slipping towards the river on numerous occasions over the history of the railway. During the last Ice Age, the valley of the River Severn was scoured out by glacial action and bands of different types of material were deposited at varying depths. This subsequently resulted in the formation of 'slip-planes' where the different layers can slide over each other, particularly when placed under a load such as the presence of a railway line and especially after periods of heavy rain. Slip-planes exist throughout most of the valley but have resulted in areas of major instability at [[Jackfield Halt|Jackfield]] and Sterns.<ref name=Sowden>[[Bibliography#Books|Sowden (2012)]] pp. 12-14.</ref> The slip plane causing the movement in this area is located at a depth of around 20 metres below the ground surface.<ref name=BranchLines202406>[https://www.svrlive.com/bljun24 Branch Lines June 2024, ''More concerns at Sterns'']</ref>
The line of telegraph poles adjacent to the railway at Sterns vividly illustrates the ground movements that have taken place. One post which stood next to the track until shortly before 1979<ref>SVR News 52 p26</ref> has been carried a significant distance towards the river by slips since that time and is now only just visible in the trees towards the river. The post is mentioned in the Railway's [[From The Window]] booklet as one of the items to see during the journey and it carries a yellow flash to make it more visible.
Sterns_20160514.jpg|The cap of the 150 foot retaining wall alongside Sterns Cottage
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===2014===
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Sterns_20140316.jpg|Dip in the line seen from the DMU
Sterns_2_20150228.jpg|Evidence of 2014 repair work is still visible in 2015
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===2020-2023===
In spring of 2022 Walsh and SVR staff undertook a further project. A deep area of ballast had developed from successive tamping over the years. 300 cubic metres of embankment comprising around 150 tonnes of ballast and 650 tonnes of fill material were replaced with around 400 tonnes of Leca (lightweight expanded clay aggregate) and 40-60 tonnes of ballast, at a total cost of £81,209.<ref>SVRH Report and accounts up to 2 January 2023</ref> This reduced the weight on the embankment, thereby lessening the progressive movement.<ref>[https://www.svrlive.com/blfeb22 Branch Lines, February 2022] (Retrieved 7 March 2021)</ref>
Both projects are were hoped to mitigate the problems, but neither is was intended to provide a lasting solution.
Electronic ‘tilt monitoring’ 'tilt monitoring' equipment was fitted in February 2021<ref>[https://www.svrlive.com/blmar21 Branch Lines, March 2021] (Retrieved 7 March 2021)</ref>. Following the insolvency of the provider this was taken out of use in 2023.
===2024===
With ground movements continuing to cause concern to the Railway, new tilt monitors were installed in February 2024, together with blue 'ground-alignment markers', to monitor movement in the near-surface soils. In June 2024 specialist contractor 'Ground Investigation Specialists' drilled through the rock to a depth of 23 metres to install new boreholes to monitor the movement more accurately.<refname=BranchLines202406/>[https <gallery mode=packed heights=200px style="text-align://wwwleft">Sterns_ground-alignment_markers_20240502.svrlivejpg|Ground-alignment markers, May 2024Sterns_borehole_drilling_20240605.com/bljun24 Branch Lines jpg|Borehole drilling, June 2024, . The 'moving telegraph pole'More concerns at Sterns'']</ref>is to the left.<br clear="all"/gallery>
==Speed restrictions==
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File: Sterns_1_20150228.jpg|Another view of the displaced telegraph pole (highlighted)
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