24.03.17
Moel y Golfa (SJ 290 125, only bwlch surveyed)
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| Moel y Golfa (SJ 290 125) in the background with the Trimble positioned on the area of the bwlch |
I’d wanted to visit this
bwlch for quite some time as it’s relatively near to where I live and
conveniently placed beside a main road with access to it through a gate. As I parked on the side of the adjacent minor
lane and donned my wellies a chill in the air and slightly misted grey skies predominated.
The bwlch in question is
that for Moel y Golfa, which is the high point of the Breiddin and listed as a Dominant, Marilyn, Hump and Pedwar. Its summit was
one of the first that I’d surveyed with the Trimble in December 2013, and it’s
always good to then complete the task of adding surveyed heights to
both summit and bwlch for any hill.
Once in the field I
followed the hedge line northward for 70 metres before heading east, I’d come
prepared with a 10 figure grid reference for a centralised bwlch position based
on the valley to valley contours, but before finding this spot I wanted to
independently judge where the critical bwlch lay. I found this point relatively easy and left
my rucksack there, and then followed the 10 figure grid reference using the Trimble
as a hand-held GPS to where map contours suggest the critical bwlch to be
positioned, I then left the Trimble there and walked away to get an overall
view of the position of one to the other, as the position of the Trimble was on
the upward hill to hill traverse I walked back to it, picked it up and
concentrated on the position of my rucksack, I looked at this position from a
number of directions and decided that this spot was as good as I could judge by eye.
As the Trimble gathered
data I stood back and hoped that a passing farmer wouldn’t become inquisitive
and wonder why a person had seemingly abandoned his rucksack in a field and was
standing motionless 50 metres from it whilst scribbling in a notebook. Thankfully this part of Shropshire remained
relatively quiet, and except for the traffic on the adjacent A 458 road nothing
much stirred.
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| The Trimble GeoXH 6000 gathering data on the bwlch area of Moel y Golfa with the Breiddin in the background |
Once the allotted data
were collected I closed the Trimble down, packed it away and headed back to my
car for the onward journey to Shrewsbury to visit a friend and get Euros for
next week’s visit to Lisbon. By the time
I’d done both the sun had broken the morning’s grey sky and pleasant afternoon
sunshine meant that my planned survey of the high point of Cefn Digoll and its
connecting bwlch looked as if it was going to be a relaxing affair.
%20-%20LIDAR%20bwlch%201.jpg) |
| LIDAR bwlch image of Moel y Golfa (summit at SJ 290 125) |
Postscript:
Since the survey of this hill full LIDAR coverage
is now available. The LIDAR (Light
Detection & Ranging) technique produced highly accurate height and
positional data that is now freely available for England and Wales. Consequently the numerical details for this
hill has been analysed using this technique, resulting in the LIDAR height and
position for its bwlch being used.
Survey Result:
Moel y Golfa
Summit Height: 403.2m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)
Summit Grid Reference: SJ 29074 12528 (from previous Trimble GeoXH 6000 survey)
Bwlch Height: 140.8m (LIDAR)
Bwlch Grid Reference: SJ 32605 11659 (LIDAR)
Drop: 262.4m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Dominance: 65.09% (Trimble GeoXH 6000 summit and LIDAR bwlch)
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