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Dog Walks Wales Llyn Brianne Reservoir Gallery

Grand Tours days out

South Wales Dog Friendly Walks - Llyn Brianne Reservoir

Llyn Brianne Reservoir

Llyn Brianne Reservoir: What's in a name?

No one had heard of the word Brianne until the proposal for the new dam was put forward.  It is in fact named after a stream, called ‘Nant y Bryniau’, which literally means a stream in the hills.  

At some time a mapmaker had misspelt the word Bryniau, a common occurrence when people are not used to the Welsh language. So now it is known as Brianne. Llyn y Bryniau would have been a far nicer name; it means, 'lake of the hills'.

"Llyn" is Welsh for Lake.

Llyn Brianne Reservoir

Llyn Brianne Dam: Where to build the dam

When it was first discussed the thought of a reservoir above the village brought considerable fear in those who lived lower down in the valley.  Locals lower down were worried that the dam wall might collapse and there would be a great flood.  
Consequently there was considerable objection to its location. The objectors wanted it to be built further up the valley.  

In December 1966 a Public Enquiry was convened to finalise a decision on its construction.  On 3rd July 1968 the West Glamorgan Water Board (Llyn Brianne) Order 1968 gave the go ahead.

Many of the local people felt the Public Inquiry was a foregone conclusion.  The fact that it would affect very few people was probably a primary consideration.  One unoccupied farm, Fanog, some farmland and a large plantation of oaks, conifers and some rare plants were the only real casualties.

Llyn Brianne Reservoir valleys

Llyn Brianne Reservoir: Protests prevent road building

While the protestors were unsuccessful in preventing the construction of the dam, they did prevent a new roadway through the beautiful Doethie valley from being built.  Without their efforts a wonderful part of Wales would have been decimated.
There was still fierce opposition to the reservoir and many to this day wish they had won the fight.   Many remember the valley before forestation and the reservoir.  It was a beautiful place.
However for those of us now driving around the Reservoir, it is still a beautiful place, and what we cannot see we do not miss. Wales seems to have been chosen for a lot of reservoirs because the valleys were sparsely populated, and so few people were displaced, and because the rainfall is particularly high. Certain valleys could be closed off at one end, thus permitting a whole host of reservoirs to be built.

If you want to live in a good climate, do not move to where there are lakes, lochs or reservoirs!

Llyn Brianne Reservoir men walking over the dam

Llyn Brianne: Opened in May 1973

The roadways were widened and heavy construction plant trundled through daily. Strangers with a variety of accents moved into lodgings and rented houses in the village and in the surrounding area.  

Llandovery was awash with engineers and construction workers.  Local businesses did very well and within a very short time village life had changed completely.  Others couldn’t wait for normality to return.  Every day convoys of large lorries headed up one side of the valley and back down the other, hauling anything and everything to the site.  Bus loads of people came to see the worksite of the largest dam of its type in Europe.

On the 15th May 1973 the dam was officially inaugurated by Princess Alexandra.

Llyn Brianne Reservoir view of old quarry

Llyn Brianne Reservoir: A tourist attraction now

Once the last piece of machinery had left the valley, life did return to some normality.  The place was quiet once more but where people used to come to see Twm Siôn Cati’s cave,  now they came to see the new reservoir.
The new road system connected the Cambrian Mountains to Tregaron and beyond. Water is provided for West Glamorgan and areas further afield.  

Sometimes the level has dropped and Fanog farm has emerged eerily from its watery grave.  Word got around and soon there were hundreds of visitors climbing all over the old ruin.  Someone even put a, 'For Sale,' sign on it.  There were no takers.

Llyn Brianne Reservoir water spillway drain

Llyn Brianne: Hydroelectric Power

The spillway of the dam is a notable tourist attraction when the reservoir is spilling.

The dam is the UK's tallest, standing at a height of 300 ft (91 m), and is the world's largest clay core dam.

In 1996 the reservoir spillway was increased by 1 metre in height and a hydro electric generating station was added at the base of the dam. When all three turbines are working, it generates 4.3 megawatts of electricity.

Llyn Brianne Reservoir dam footpath

Llyn Brianne Dam: Construction

The dam is a crushed and larger rock clay filled dam, all materials being obtained in the area itself. It is a man-made mountain blocking the valley.

The clay was taken from higher up the valley near Soar y mynydd chapel closer to Tregaron.

Much of the rock was quarried on site; this is now where you can park.

An on-site stone-crusher was used to reduce larger rocks to the various sizes required. A round-the-clock labouring system enabled its completion almost two years ahead of schedule.

Llyn Brianne Reservoir Jack the dog inspects view of the valley from the path over the dam

Llyn Brianne Reservoir: Standing on the Dam

When you visit Llyn Brianne today you will be hit by the solitude and tranquillity of the place.  Sometimes it is eerily quiet here.  

Stand on the dam wall where Jack the dog is above and look out over the valley below. It is then that you realise what a massive structure this is.  

It has been altered since 1973.  Its capacity has been increased and a hydro-electric station has been built at its base.  

It still regulates the supply of water in the river Tywi and maintains the water supply to homes and industry in South Wales.

Llyn Brianne Reservoir dog walking along banks of reservoir

Llyn Brianne Dam: Kayaking now banned on the slipway!

Llyn Brianne has been popular with extreme sport enthusiasts and in 2008 the 300ft tall Llyn Brianne Dam acheived national notoriety when a video of kayakers hurling themselves down the spillway at speeds of 45mph was posted on Youtube!

The canoeists reach speeds of up to 45mph. It's actually so dangerous that the water authority has now banned this sport on the dam's slipway.

Hitting a wall of water at 45 mph is not so safe and Kayakers could lose their heads on the steel ridge at the bottom. Drowning, once you are knocked unconcious, becomes a distinct probability.

Llyn Brianne Reservoir dog walk tracks

Llyn Brianne Reservoir: Construction

The reservoir was constructed by Wimpey in the late 1960s and early 1970s to regulate the flow in the River Tywi.

It supported large potable water abstraction at Nantgaredig in the lower reaches of the river near Carmarthen, providing water to the Felindre water treatment works.

The treated water is piped to a large area of South Wales and up to the borders of Cardiff.

Under the reservoir there are a couple of houses which were flooded to make way for the reservoir. Before the water level was raised, it was possible to walk to Fannog farmhouse as a "For Sale" sign was once erected on it.

It is still possible to see the top of the house when the water levels are low.

Llyn Brianne Reservoir dog walk wet forest path

Llyn Brianne Reservoir: Where to find it

Llyn Brianne Reservoir is 5 miles (as crow flies) North West of Llanwrtyd Wells, on the headwaters of the river Towy, near to its source in the Cambrian Mountains.

The reservoir was built in 1972 by damming a section of the river Towy to supplement flows in the river during low flows, and as compensation for extracting water supplies some 40 miles downstream at Nantgaredig, near Carmarthen.

The dam is believed to be the UK's biggest at a height of 300ft.

Llyn Brianne Reservoir surrounded by mountain scenery

Llyn Brianne: Was it prettier as a valley?

Locals complain that the dam and reservoir although beautiful in their own right, can in no way be compared to the beauty of the valley and gorge that the dam and reservoir has replaced.

Proposals to deliver electricity generated at the dam to the National Grid via a line of pylons down the Towi Valley fortunately caused such a storm of protest that after a sustained campaign the cable was buried out of sight. It lies mainly in a trench cut in and beside the Rhandirmwyn to Llandovery Road.

Llyn Brianne Reservoir dog walking tracks

Llyn Brianne Reservior: A haven for Bird watchers and Mountain Bikers

The Upper Towy Valley and Llyn Brianne is still one of the most beautiful areas of Wales.

The area is a haven for bird watchers, anglers, mountain bikers and walkers.

Mountain Bikers are particularly well catered for with nearby Llanwrtyd Wells being a centre for the sport with several trails commencing in the town. There's the the Mynydd Trawsnant Trail, the Irfon Forest Trail and the Esgair Dafydd Trail.

Llyn Brianne Reservoir valley

Llyn Brianne: Also known as Little Switzerland

Although several miles to the north of the village of Cil-y-cwm, the building of the Llyn Brianne Dam had many subsequent and profound effects, not only on the inhabitants of the Upper Towi Valley, but also on the fishing in the Valley and River Towi.

Llyn Brianne reservoir was originally built to satisfy the growing demands of heavy industry in Swansea. During the Industrial Revolution Swansea was a major industrial centre, known as 'Copperville'. There are paintings of the lower Swansea Valley covered in smokestacks.

The demand of industry for water, notably the tin plate works at Felindre and a smelting plant at Llansamlet exceeded the then available supply. Ironically, both these have since closed down. Consequently some of the water from Llyn Brianne is surplus to Swansea's needs.

The extra water now goes into the general water supply, to Llanelli, across West and South Wales and as far East as Cardiff.

Llyn Brianne Reservoir dog walk picnic area

Llyn Brianne: Highest Dam of this type in Europe

The dam, built with a clay core and rock fill, is believed to be the highest of its type in Europe.

Work started on the reservoir in October 1968, and the first water was supplied in October 1972. Princess Alexandra formally opened the reservoir in mid 1973

In the early 1990's Welsh Water decided to increase their investment to make Llyn Brianne produce economically viable amounts of hydro-electricity.

Llyn Brianne Reservoir dog walk picnic area

Llyn Brianne Dam: Adapted for Hydro-electricity

In 1995/6 the height of the spillway was raised by one metre, raising the water level in the reservoir.

A concrete extension was built into the original clay core dam and the rock walls raised to cover it.

This increased the capacity of the reservoir from 13,400 million gallons to 14,200 million gallons, a total of 62 million tonnes of water.

Three Francis-pattern turbines were installed in a hydro-electric plant, one capable of handling the normal 1.5 million gallons/day summertime flow from the reservoir. This operates all the year round.

The larger, turbines run from November to March, when Winter rains keep the reservoir full, together producing

4.3Mw – enough electricity to power a small town. Its electricity is delivered into the National Grid at Llandovery.

Thanks to local opposition, the original plans for an unsightly line of pylons down the Towi Valley was substituted for a cable buried beside the Rhandirmwyn to Llandovery road.

Llyn Brianne Reservoir dog walking picnic area

Llyn Brianne: When you see the Plumes of Water

The dam is 299 feet high and 951 feet long, made of crushed and larger rock clay filled construction.

During the summer the water flow drives a single turbine.

During the winter and spring there are three turbines operating, producing 4.3 Megawatts of electricity.

When the water in the dam is below the spillway, you can see a plume of water coming from the turbines as the water exits through the lower drain-off, while in winter it will overflow down the spillway.

Llyn Brianne Reservoir picnic area dogs at play

Llyn Brianne Dam - Featured Walk on Craig y Nos Castle's main site

Location: Llyn Brianne, including scenic circular drive

Directions: Set your sat nav to take you to Ystradffin but set it to go via Abergwesyn. Check where you are going against the map in case your sat nav does not take you on the correct lanes. This route takes you on a scenic drive with lots of views. Lanes are narrow, winding and steep in places as you drive through deep valleys with sheer drops on one side of the road, and several blind bends and summits.

The route takes you through a series of valleys and forests and up some steep hills with switchback roads, until eventually you see the waters of Llyn Brianne before you. There are some nice stopping spots along the shore before you get to the dam itself. The drive around the reservoir alone is several miles long.

Before you get to Ystradffin you will see a sign to Llyn Brianne Dam, where you can park up in an area that used to be a quarry (presumably providing the material for the dam). You can then walk over the Dam and around the side of the Llyn Brianne reservoir. This is a nice dog walk and includes some forest trails. However you cannot walk all the way around the dam. It is huge. So this is not a circular dog walk.

I noticed sheep sometimes get on to the dam path from the fenced in mountain grazing above, so keep an eye on dogs running too far ahead off the lead in case they put up a lone sheep.

Llyn Brianne Reservoir picnic area
Llyn Brianne Dam: Dog-Walking and camping

Though it clearly is not allowed, I have seen mobile homes and campervans parked up in the quarry area by the dam. There are some discreet areas round the far end where you can 'hide'. I doubt there is much policing of this but it is not a designated campsite area.

However the roads are so narrow and windy in places that I would not consider it practical to drive a motor home or camper into this area. You certainly could not do the scenic drives in anything other than an ordinary car as some of the roads are a high gradient and have switchback curves.

Assuming you are staying at Craig y Nos Castle, you will not be needing to camp here. But to get in a good dog walk of say 7 or 8 hours, it is worth setting off early, parking up at the dam, and taking a picnic with you. For my own part, I like the circular drive around the reservoir, with a couple of hours allowed for the dog walk. There are several stop-off points around the reservoir where you can let the dogs out for a run before you get to the dam itself.

One of the stop-off points with a nice little private beach is shown in the picture above.

Llyn Brianne Reservoir dogs at play

Llyn Brianne: Stop-Off Point and Private Beach

As you drive around the reservoir, you will at some point pass through a wooded area. Look out for side turnings off to the reservoir's water edge. I chanced across this private bay and beach area, shown in this sequence of pictures, with excellent views down the reservoir. Much fun was had throwing sticks for the dogs, though on one occasion we had to watch out for a rather aggressive swan.

The area shown above comes complete with a sandy beach, and is clearly popular for the occasional picnic/ barbecue, as I found piles of stones in circles around several areas of burnt grass.

I imagine watching the sun set over this scenery would be very dramatic, but you are so far from anywhere, you would not want to miss the views on the rest of the drive around the reservoir by staying so late here.

Llyn Brianne Reservoir dogs in car
Llyn Brianne Reservoir hidden picnic area parking space

Llyn Brianne Reservoir: Picnic Spot with Private Sandy Beach

Herre we are arriving at the parking spot you need to look out for, to find the picnic area and private beach referred to in the previous pages.

It is not particularly marked as such, so you might have trouble finding it. Look out for a parking area on one side of the road with a forest walk on the opposite side of the road.

The parking area here is presumably for both the forest walk across the road, and the peninsula area that leads off towards the reservoir on the same side of the road as the parking space. It will only allow a couple of cars to park there. So as long as it is empty you will know you have the peninsula area to yourself.

Llyn Brianne Reservoir through trees

Llyn Brianne Reservoir: View through trees

Llyn Brianne is very large and it can take a couple of hours to leisurely drive all the way around it. Sometimes you are quite high, looking down, at other times you leave the reservoir behind you, and then it reappears again.

Llyn Brianne Reservoir dog walk path

Llyn Brianne Reservoir: Another stop-off point

This stop-off point was nothing special, just one of many little tracks going down to the water's edge. We stayed here five minutes only.

Llyn Brianne Reservoir spillover sluice drain and valley

Llyn Brianne Reservoir: The Spillway

In the above picture you see the slipway, or 'spillway', that is used for the water to spill over into, when the Dam is very full in the winter. This is the slipway that now drives a hydropower turbine and which some daredevils kayaked down (see earlier video link on these pages).

Llyn Brianne Reservoir dam spillway

Llyn Brianne Reservoir: The Spillway

In winter the water overflows down the spillway shown above.

The dog walks featured earlier involve walking over the dam to the other side where there are dirt tracks which presumably go all around the reservoir - at least, the tracks went as far we we managed to walk.

Llyn Brianne Reservoir sign plaque

Llyn Brianne Dam: Plaque

Llyn Brianne Reservoir dam dog walk

Llyn Brianne Dam: Walk over it here

The other side of this dam there are miles of tracks you can walk along. No cars though as it is gated both ends.

Llyn Brianne Reservoir dogs walking on dam

Sheeba and Bryn on the dam at Lynne Brianne Reservoir. You can walk over the dam heading to the left, and having crossed over the dam you head around the dam on rough tracks curving around to the right.

We have never gone all the way around as the tracks goes on for miles. You cannot do a circular dog walk around this reservoir as it is too large. However one may be fooled on this walk into thinking one is coming back on a circle as you go around a long curve that heads back towards the dam for a while - however it doesn't!

You might be able to cycle around more of it though. If walking the dogs, take a picnic and walk in one direction for an hour or two and then walk back again.

Llyn Brianne Reservoir Jack the dog admires view

Llyn Brianne: The cycle route

If you have mountain bikes with you (or you can hire them locally or from us) then the link to the Llyn Brianne Cycle route may be useful.

If you have not got bikes with you, you could choose to drive on the road parts or walk the track parts of this route.

Llyn Brianne Reservoir dogs walking joined on lead to prevent one chasing after sheep

Llyn Brianne Reservoir: Dog Walk & Sheep

As we walked along on the outward bound journey of this track, we found some sheep had escaped their mountain grazing areas. As Jack won't chase Sheep but Sheeba, if she gets out of my line of sight, will seize the opportunity if she thinks I am not watching her, I used to link the two dogs together as shown above.

This practice is not recommended however, as if either dog is aggressive to the other, serious injury could be caused as neither can get away from the other. My mother would never chance this with her Rhodesian Ridgebacks, who most likely would get themselves in a tangle and being a gangly breed with a lolloping bouncy gate, they might even break a leg or jump up and twist a neck.

Also if there are other pedestrians around, two loose dogs running either side of someone will knock them over.

However I have found Sheeba and Jack are fine when they are attached. They are both low to the ground, Jack is not very excitable, so it works for them. In very remote areas where you might get sheep but no people, and you want to let the dogs have a free run, this worked very well but I would not do it in an area with other walkers around!

I find it is when they are separate that Sheeba bullies Jack by chasing him if he runs off, effectively preventing Jack from taking the lead.

This prevention of any other dog getting in front is a habit with an insecure dog that wants to dominate the pack; they make sure only they are in the lead. Consequently Sheeba nowadays is generally muzzled to prevent her nipping Jack or indeed any other dog she might come across, which she will do if she is out of my line of sight or my attention is taken away in conversation with someone. I cannot be 'watching her' all the time, so Jack as the father figure plodding along prevents Sheeba from charging off in chase.

Should I spot Sheeba chasing off, and I call her, she will always break off the chase and come back, which is not something that can be said of many dogs. Many owners keep their dogs on the lead so much that they have no freedom and no response to the 'call' command when it is needed.

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