Wednesday, 28 February 2018

Mapping Mountains – Trimble Surveys – Walton Hill

29.01.18  Leopard Hill (SO 872 555) and Elbury Hill (Son 869 558)

The summit of Leopard Hill

Having visited Worcester on a number of occasions over the last two years I thought it time that I investigated the highest part of the city.  This accolade had been accorded Leopard Hill which is positioned in the eastern part of the city and is hemmed in by three B roads and a number of housing estates; thankfully the upper part of the hill has escaped development and gives a brief interlude from the concrete and brick that large conurbations bring.

Leopard Hill is given a 98m summit spot height on contemporary Ordnance Survey maps and is crowned by a metal fenced water tower.  To the north-west of the hill are further areas of land that have escaped urban housing estates, these are Elbury Hill and Gorse Hill, the latter is given a 92m summit spot height on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, whilst the former is tantalizingly also given a 98m summit spot height on this same map.  However, the summit area of Elbury Hill has a number of covered reservoirs positioned on or close to this hill’s high point and as these structures are frowned upon as far as the natural height of a hill is concerned I wanted to investigate and see if an on-site visit and a survey with the Trimble GeoXH 6000 could confirm which hill is higher.

Before detailing my visit it’s best to mention that the summit of Elbury Hill is shown with a triangular symbol on the Ordnance Survey Six-Inch map published in 1886, which is given the height of 323ft (98.5m) on the Six-Inch map published in 1905.  The latter map has a covered reservoir marked to the north of the triangular symbol, whilst the map from 1886 just has the symbol; this implies that the 323ft (98.5m) height was taken to natural ground before the covered reservoir was constructed.  The TrigpointingUK website details a block that replaced a pillar in 1970 and which is adjacent to a mast that stands in one of two covered reservoir compounds and therefore is off limits for budding surveyors, this mast is also recorded in the OS Trig Database at SO 86872 55812, unfortunately a height is not recorded for it.  The 323ft (98.5m) height would have been to the old pillar which is given the position of SO 86915 55816 in TrigpointingUK.  

Extract from the Ordnance Survey Six-Inch map published in 1886

Extract from the Ordnance Survey Six-Inch map published in 1905

I parked between the two hills just off the B 4537 Tolladine Road and walked to its high point which is where the col between the hills is positioned, and continued down the road looking for a public footpath giving access to the northern part of Leopard Hill, when found this led through a housing estate toward the upper part of the hill, with the continuation of the path beyond the houses mud splattered from the morning’s rain.

The high point of Tolladine Road

The afternoon’s forecast was good and deep grey cloud interspersed with radiant blue gave a dramatic colour to proceedings.  The muddy path led up to rougher grass and the summit area of Leopard Hill with its metal fence and squat water tower.  I walked around the compound and assessed the ground from various directions and judged land to the west of and adjacent to the structure to be the highest.

The Trimble GeoXH 6000 gathering data at the summit of Leopard Hill

Thankfully the Trimble achieved its 0.1m accuracy level before data should be logged relatively quickly, and as it beeped away gathering the allotted 300 individual data points I stood back and admired the view, which took in much of Worcester and the Malvern hills beyond.

The Trimble GeoXH 6000 set-up position at the summit of Leopard Hill

Once data were stored I retraced my inward route back to the B road and walked back up to the connecting col between the hills and followed a footpath on the right which led across Elbury Park Road and continued to a track giving access to the upper part of Elbury Hill.  On my way up I passed and said hello to a couple of dog walkers as the sky turned a menacing grey colour and which kept the sun at bay for the majority of the duration I was on top of the hill.

The track continued around the upper northern part of the hill, whilst I opted to leave it favouring wooden steps that led directly to the summit area.  There are two large fenced compounds on the summit of Elbury Hill, whilst the ground between is open.  I spent a number of minutes assessing the lay of land and having judged the high point to be on the open ground close to its periphery and only just higher than the encircling brambles, vegetation and small trees, I placed the Trimble on top of my rucksack, measured the offset between its internal antenna and the ground below and waited for five minutes of data to be collected.

Gathering data from where I judged the summit of Elbury Hill to be positioned with the southerly of the two compounds and where the high mast is positioned, in the background

During data collection I investigated the compounds, took a number of photos and admired the view overlooking Worcester with the Malvern hills beyond, I also contemplated the open ground where the Trimble was placed and wondered if the whole of this hill’s summit including the open ground consists of one big covered reservoir, or if it consists of a number of these structures, but as the majority of covered reservoirs I have seen on top of hills have been situated in fenced compounds, I thought the open ground to be an indicator that a covered reservoir is not below it.  Once five minutes of data were stored I walked the perimeter path around each of the fenced compounds, the second of which houses the high mast and OS block and which is out of bounds, and then used the wooden steps as my descent route.

Looking through the metal fence in to the northern compound

Worcester with the Malvern hills beyond

Before heading back to my car I contemplated getting a data set from the col, which would at least give a drop value for the lower of these two hills.  However, Tolladine Road was particularly busy and it would have meant placing the Trimble in severe peril, which I am prone to do on occasion, this time I was happy enough to turn my back on the col and wander down the road to my car. 

Survey Result:

Leopard Hill

Summit Height:  97.2m (converted to OSGM15)

Summit Grid Reference:  SO 87286 55551

Drop:  c 25m (col swap with Elbury Hill)

Dominance:  25.92%

Elbury Hill

Summit Height:  97.4m (converted to OSGM15)

Summit Grid Reference:  SO 86900 55854 (recommended summit relocation for qualifying Tump)

Drop:  c 53m (col swap with Leopard Hill)

Dominance:  54.84%

Although the recommendation is to swap the position of the col and therefore the drop value and status as Tump of these two hills, the height difference produced by surveying with the Trimble GeoXH 6000 is not great.  However, the resulting data is the best available at hand, with the caveat that higher ground may exist close to where the Trimble was placed on Leopard Hill and that higher ground may exist in the southern compound close to, or at the position of the high mast on top of Elbury Hill.  The added complication are the covered reservoirs on Elbury Hill and whether the open ground between the two compounds can be thought of as being natural.

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