Carol couldn't wait for further responses from Martin Doyle of Plas y Brenin and it was a lovely day the other Friday (13th) so I accompanied her to have a recce around the Afon Lligwy at Capel Curig (the potential site of our proposed river diving training)
We were both equipped with a map each - so no worries there!
We started by the Cobden's Hotel car park (all of this assumes permission etc. to clamber across fields, through woods, along footpaths etc.) Here there is very easy access to the water, a rush of water under the footbridge into a large pool, the river then divides around an island or two, to the right the water runs fast over shallow boulders, this might be a good site to see what speed of running water we can cope with as the entry point is out of the current. Also perhaps to creep towards the bottom of a waterfall and see what it's like with a safe get-out plan – (in case it's not nice).
The water was lovely and clear all along.
We played pooh sticks to time the rate of movement of water along approx. 10m, under this footbridge we got 0.7 knots or 0.8 mph - which sounds a lot slower that it looked!!
Further upstream there were more nice pools after lots of waterfalls (short ones) with possible access across fields from the roadside - or along the footpath on the other side which would be a longer walk.
In one of these pools immediately opposite the old garage with red frontage we measured a flow of 0.65 knots or 0.75 mph (figures for these sums gleaned from Wikipedia so they must be accurate - not to mention our guesstimate of what 10 metres looks like!)
Further upstream again, the banks were part of the Forestry Commission - Bryn Engan - including some mountain biking paths through the woods. By Plas Curig (as marked on the map) there was a new FC bridge and here we found a torn dry suit wrist seal lying on the path?????!!
Opposite the Bryn Tyrch there was what we decided was a riffle bit with an area of calmer water which might be deeper.
We also went to Plas Y Brenin and looked at their canoeing pool - which also looked like a good site but might be very shallow.
Hopefully we'll get more info from PyB people about depths of the water here and there, when we do our survey of the Conwy we will include shallow waters where crawling/wading is required.
The main obvious hazards we noted along this stretch were boulders and tree branches in the water
Thoughts about techniques/equipment etc. as we went along were:
For initial recce's of sites we would need a plumb line (marked in depths) to use from bridges etc.
Ropes could be used for a number of purposes:
- a weighted line for an underwater transect (as used in underwater surveys we've done at other places)
- a line across the river on the surface to catch divers swooshing off unexpectedly in the wrong direction
- a line along a piece of bank for a diver to grab and pull along if examining a short section by a bank
Also initial or second visits - just snorkelling may be best to then decide whether SCUBA gear would be appropriate
Wheel barrows and trolleys would be useful for humping gear
If we used some sort of grapple we would need to consider what if any damage this might do to the bottom - an initial snorkel might confirm whether a grapple would be of any use anyway.
It's going to be handy to have lots of shore cover
Errr - that's it
Lig
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