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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.
===2007===
In the [[2007 Storm Damage|Summer 2007 storm damage]], the first severe thunderstorm did not affect Sterns. However further slips began in the following weeks as the wet weather continued, both at the area normally affected and further to the north by Sterns Cottage, the house alongside the line on the side nearer the river.
Part of the solution involved building a 150 foot long piled concrete retaining wall alongside Sterns Cottage. This required 75 24-foot long vertical piles reinforced by 37 42-foot long angled soil-nails and covered by a concrete cap<ref name=Sowden/>.
<br cleargallery mode=packed heights=200px style="alltext-align:left">Sterns_20160514.jpg|The cap of the 150 foot retaining wall alongside Sterns Cottage</gallery>
===2014===
In mid-February 2014 evidence emerged that further subsidence was taking place when a significant dip in the line appeared at the north end of the Sterns area close to Sterns Cottage. A 'stop and proceed with caution' restriction was put in place until repairs could be completed over the following months. A large concrete sleeper wall was built at the toe of the slip and packed behind with approximately 150 tonnes of ballast. This was topped off with around 200 tonnes of graded stone in order to help to stabilise the slip and drain the water from the embankment. Full-time staff, with the help of [[Other rolling stock visiting the SVR|hired in plant]] completed the repairs to the line<ref>SVR Live April 2014</ref>.
<br cleargallery mode=packed heights=200px style="alltext-align:left">Sterns_20140316.jpg|Dip in the line seen from the DMUSterns_2_20150228.jpg|Evidence of 2014 repair work is still visible in 2015</gallery>
===2020-20222023===[[File:Sterns_20200808.jpg|thumb|300px|right|Lineside view of the drainage ditch and repair works uphill from it, looking north]][[File:Sterns_Drone.jpg|thumb|300px|right|Aerial view of the repair works looking south (River Severn to the left)]]
Following [[Severn Valley Railway Timeline 2020-2029#2020|extensive flooding in February 2020]] land movements were again observed. A comprehensive drainage network was proposed to collect rainwater and transport it to the river in an efficient manner before it could get down to the slip planes and exacerbate the problem.<ref>[https://www.svrlive.com/bljun20 Branch Lines, June 2020] (Retrieved 26 June 2020)</ref> Contractors Walsh Construction completed this water management work by 29 July as planned, with the final item being the lining of the existing drainage ditch with concrete canvas. The work was funded by £120,000 from the [[Severn Valley Railway Charitable Trust Ltd|SVR Charitable Trust]].<ref>[https://www.svrlive.com/blaug20 Branch Lines, August 2020] (Retrieved 3 August 2020)</ref>
Both projects were hoped to mitigate the problems, but neither 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.<ref name=BranchLines202406/> <br cleargallery mode=packed heights=200px style="alltext-align:left">Sterns_ground-alignment_markers_20240502.jpg|Ground-alignment markers, May 2024Sterns_borehole_drilling_20240605.jpg|Borehole drilling, June 2024. The 'moving telegraph pole' is to the left.</gallery>
==Speed restrictions==
<gallery>
File: Sterns_1_20150228.jpg|Another view of the displaced telegraph pole (highlighted)
</gallery>
