18.09.19
Moel Fechan (SH 993 632, only bwlch surveyed)
This was the fourth of
nine planned roadside bwlch surveys during the day and each had either been
LIDARed, examined in detail via 5m contouring on the OS Maps website or driven
to and over in a digitised Google car assessing the lay of land and the ups and
downs of the hill to hill and valley to valley traverses.
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| The bwlch of Moel Fechan |
As LIDAR does not cover
the area of this hill’s summit or connecting bwlch I was reliant upon map
contours and the Google car for pre-visit assessment, and then an on-site
inspection when there.
The ‘there’ part was a
grass verge beside the A543 road close to a cross roads intersecting with the
B5435 and a minor road. I’d already
found a parking place via driving the Google car and was soon loading up with
all necessary equipment including my newly purchased surveying steps which are
ideal for car roof surveys as they give height to see the screen to create the
file necessary to start gathering data.
They are also ideal for grass verge roadside surveying as they give the
Trimble an added semblance of protection when balanced on top of my rucksack
and importantly a higher position which enhances satellite reception.
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| The set-up position at the bwlch of Moel Fechan |
As I approached the
cross roads and turned right on the B5435 to park in a pull in place close to a
gate, a tractor with attached hedge cutting equipment was parked nearby. Leaving my car I walked the short distance up
the A543 to where I judged the critical point of the bwlch to be
positioned. As I did so the tractor
started chugging up the road conveniently cutting the grass verge where I was
just about to set the equipment up. I
flagged the tractor down and quickly explained what I wanted to do, the driver
said he wouldn’t be heading back up the road for 15 minutes or so, which was
all I needed, and once the grass was cropped I unfolded the surveying steps and
positioned my rucksack on top with the Trimble placed atop the latter; giving a
measurement offset of 0.95m between its internal antenna and the ground below.
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| Gathering data at the bwlch of Moel Fechan |
A few vehicles zoomed past
as the Trimble beeped away gathering data.
During data gathering I stood beside the road 50 metres or so from the
equipment and waited for the allotted data to be gathered and stored.
I left the Trimble gathering
data for six minutes and then closed it down happy in the knowledge that
another bwlch survey was complete. All
that remained was to pack the Trimble away, fold the steps up and walk the
short distance back to my car. Next stop
the bwlch connecting to Foel Gasyth.
Survey Result:
Moel Fechan
Summit Height: 372m (spot height)
Summit Grid Reference: SH 99335 63247 (hand-held GPS via DoBIH)
Bwlch Height: 299.2m (converted to OSGM15, Trimble GeoXH 6000)
Bwlch Grid Reference: SH 98493 63393 (Trimble GeoXH 6000)
Drop: 73m (spot height summit and Trimble GeoXH 6000 bwlch)
Dominance: 19.56%
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