Thursday, 5 November 2015

Mapping Mountains – Significant Height Revisions – 100m Twmpau

Bersham Bank (SJ 311 481) 

This is the twenty third post under the heading of Significant Height Revisions, and the following details are retrospective as the Trimble survey that resulted in this height revision was conducted on the 13th October 2015.

The twenty third major height revision initiated from a survey with the Trimble GeoXH 6000 was conducted in the easterly lower hills of the Bryniau Clwyd range, with the hill situated on the southern outskirts of Rhostyllen, which is a south-western suburb of Wrecsam (Wrexham).

The hill had no classification prior to the survey with the Trimble as although it is prominent and rises almost directly above the A 483; it possesses no contour rings on current Ordnance Survey maps, except for those at its bwlch.

There is a circuitous path on the southern and eastern middle section of the hill; this can be accessed from a road to its east that is adjacent to an industrial estate.  Beside the road is a perimeter fence seemingly barring entrance to a path on the lower slopes of the hill, however, one section of the six foot high fence has been toppled over giving access to the public, including local people, who I was told occasionally walk up the hill.

The name of the hill is Bersham Bank and its summit is positioned at SJ 311 481.  This is the preferred locally known name for the hill and was given me when I made enquiries after my ascent.  There is no name for the hill on current Ordnance Survey maps but ‘Colliery (disused)’ appears on the map where the hill is situated.  As the Ordnance Survey detail implies, this hill is the relic of coal waste which was deposited from the workings of the Bersham Colliery which closed its operations in December 1986.

Although this hill does not possess any ring contours on current mapping, there are two hills created from coal waste that are relatively near to Bersham Bank that do possess separate ring contours, these are situated at SJ 311 469 and SJ 300 473.  The bwlch contouring for Bersham Bank is between 100m – 105m, with the height of the bwlch estimated as being c 103m. 

Therefore this hill’s new summit height is 153.6m (converted to OSGM15), as no summit contours exist for this hill this is a dramatic 48.6m increase in height compared to its uppermost hill to hill bwlch contour of 105m.

The full details for the hill are:

Cardinal Hill:  Moel y Gamelin

Summit Height (New Height):  153.6m (converted to OSGM15)

Name:  Bersham Bank

OS 1:50,000 map:  117

Summit Grid Reference:  SJ 31159 48116
Drop:  c 51m

Gathering data from the summit of Bersham Bank which resulted in this hill's significant height revision

For details on the survey that significantly revised the summit height of this hill please click {here}

Myrddyn Phillips (October 2015)

No comments: