The early May Bank Holiday weekend saw us camping and walking in the Elan Valley.  Claerwen Reservoir with its natural head of wild brown trout has been on my list of upland Llyns to try this year so it made sense to sneak off from family activities and give it a whirl.  The reservoir is at an altitude of 369 m making it a typical upland llyn set amongst acid grassland with numerous sheep grazing.  This means that it has a low alkalinity (14 µEq/l) while also having some colour (33.3 mgPt/l) given its humic status.  The reservoir has an average depth of 18 m, a surface area of 265 ha, a shoreline length of 18 km and a fetch of just over 4 km.

 

I purchased a day ticket at the Elan Valley visitor centre the day before for just £10.  I arrived at the parking at the top of the dam wall just after sunrise at 5:30am leaving the family sound asleep at the Elan Oaks campsite.  The reservoir looked stunning under a massive bright blue sky with almost no cloud. With not a breathe of wind the surface was like glass and the surrounding landscape was reflected in it like a mirror save for a swirl of fog that hung over the top end of the reservoir.  While the views were breathe taking and even more special in that I was up there all on my own enjoying the solitude disturbed only by the sheep on the hillside, this picture is enough to make any fly fisherman’s heart sink because these conditions are generally tough going on the fishing front. It is at times like these that you have to remind yourself that you enjoy fly fishing for more than the thrill of catching fish and hoping that against the odds you can winkle out a few fish.

Claerwen Reservoir Wall © FlyFishingScience, 2018
Claerwen Reservoir wall from dyfnant bay © FlyFishingScience, 2018

 

 

 

 

 

 

 

 

 

 

I started with a team of two flies on a 12 foot leader, pretty much as long a leader as I felt I could comfortably cast with a steeply rising bank behind me.  I started with traditional wet flies as there didn’t seem to be anything hatching nor any sign of surface feeding that would suggest my favoured dry flies would see any action. Nothing was forth coming at the reservoir wall so I set off to explore the possible vantage points along the bank where a fly could be cast.

Claerwen Reservoir inaccessible steep bank with loose rock.  The flat portion is 3 – 5 m above the water © FlyFishingScience, 2018
Claerwen Reservoir towards Craig Dyfnant showing the steep bank conditions and the dirt road that skirts the easterly/northerly bank © FlyFishingScience, 2018

 

 

 

 

 

 

 

 

 

 

 

I thought that I had done my homework by watching all of the YouTube videos of fishing at and driving around Clearwen plus using Google Street-view, but I was not prepared for the conditions along the bank.  Even the photos included in this article do not show how difficult the bank conditions really are.  They are super steep and comprised of loose slate and a thin covering of soil and grass in places. This makes getting down to the waters edge extremely tricky and in places down right dangerous.  Casting from above this loose scree is not possible as you are too far from the water and even with a long handled land net you would not be able to land fish.  This limits the number of places where you can get down to the waters edge meaning that for every kilometre walked the amount of places where you can actually fish is limited. While I didn’t take one, it would be very helpful to fish with a line tray, both at the reservoir wall, where the line gets stuck around the edges of the stone blocks set into the bank, and along the bank owing to the sharp slate.

I have since contacted the rangers, who have been very helpful answering my email queries, about accessing the dirt road which runs along the easterly/northerly bank with a car. I was loathe to do so on the day as there was no clear signage either way.  They have confirmed that this is a public byway but also stress that it is the single track access to the farm at the end of the road and there are very few laybys or places where you can park a car.  It would also be a bit hairy in places if you had to reverse back a long way to a passing place if you encountered another vehicle.  However, unless you are fit enough to walk 20 km there and back or around the reservoir while fishing in a day it might be an idea to use a car (or perhaps a mountain bike) to access the easterly/northerly bank with the dirt road.

Claerwen Reservoir hatching flies (folded wing cranefly – Limonia nebeculosa?) © FlyFishingScience, 2018
Claerwen Reservoir shoals of minnows amongst the rocks in the shallows of dyfnant bay © FlyFishingScience, 2018

 

 

 

 

 

 

 

 

 

 

 

The small bay formed by the steep valley of the dyfnant stream flowing into the lake offered a good stretch of bank that allowed access and the promise of wild brown trout.  The shallows are full of minnows so I tied on a black humugous and bead headed green montana.  Despite several fly changes and adding some additional length to the leader …. nothing.  While sitting having an energy bar and some water I noticed a fly sitting on the surface film in the shallows.  This suggested that the rising sun was stimulating insects to hatch so I switched to dry flies …. nothing.  With the sun well and truly truly up and mid-morning having come and gone I worked my way back towards the reservoir wall.  However, what I hadn’t figured out was that with the sun now up above the surrounding hills any attempt to fish the shore resulted in a long shadow across the water which combined with bright conditions and glass like surface conditions made things even more challenging.  So after 5 hours of fishing I called it quits and headed back to the campsite where the family were just emerging for the day and having breakfast.  I had snuck off and enjoyed almost 6 hours of fly fishing in a remote, stunning location and encountered nobody during that time.  While I didn’t catch any fish on this occasion, it was a great reconnaissance mission and I will be better prepared the next time I fish here.  Hopefully this information will also help you prepare for a fly fishing trip to this awesome location.

 

Tight Lines

Greg

  • Venue Claerwen Reservoir
  • Where Elan Valley, Wales
  • Species Brown trout