Words and pictures: Nick Small
All this rain is good right? Unless your local river has, bored with the confines of its banks, taken a meander through your house, then you probably have government ministers paddling around your garden in their new Hunter wellies looking sympathetic (or bamboozled if their name is Philip Hammond) for the 24 hour rolling news media.
It was certainly nice to see the gentle cascades of Ogden Clough transformed into something altogether more dramatic this week. “It looks like a fountain of coca cola” observed the lad, which, in the eyes of an 11 year old, is probably a good thing.
A 10 mile run across the moors above Haworth recently, up to Top Withins, was so wet that the lower legs were alternatively plunged into deep black peat bog then cleansed in the 10 inches of ice cold water running down the exposed millstone grit in torrents. This may not sound particularly pleasant and, to be honest, the first instinct is to go “eeeuuuurrrggghh, fuck!!!” But, engage with the inner child that likes to splash about in puddles and it can actually be tolerable fun. Anyway, I’m pretty sure that an expensive spa somewhere is selling the relentless cycle of mudbath and ice cold rinse as some sort of tonic for the circulation or intensive detox therapy.
16,000 litres per second
But, I digress. Last week I was in North Wales making a film about the management of all this water. Llyn Celyn Dam is pretty controversial even now, decades after its construction (to supply water to the people of Liverpool, England) involved the destruction of a village/community (very much in Gwynnedd, Wales). I won’t go into that now….it’s a good story that you can read and watch elsewhere on the interweb. What was of interest to me was the way that water is held back in this reservoir and released in a planned, controlled manner for the benefit of the River Tryweryn and the communities which it (and the River Dee) serves downstream.
It’s a complicated business, because the water in the dam is generally released through a small Hydro-electric plant, so there’s a company whose business is selling that power involved. Then there’s Welsh Water, who use the natural water course of the Tryweryn and the Dee to distribute water to their customers. Then there’s Natural Resources Wales who look at the environmental aspects of water release from the dam….flood and drought mitigation, dam safety, fisheries, pollution and leisure pursuits. Needless to say, not everyone sees eye to eye over the quantities released and the timing of release.
Just downstream of the dam is the National White Water Centre. Ostensibly, we were there to film some white water capers in various craft, pursuits which would be limited to periods of heavy rainfall without the dam and managed release.As it is, the centre is in constant communication with the dam and can request increased flow when they need it…although these requests are not always granted if other priorities (flood mitigation for instance) take precedence. It works enough for the centre to be sustainable though.
So that we could see just what a difference the extra volume of water released would look like visually, the water was, for a short period, released through two huge dispersal tunnels at a rate of 16 cubic metres per second. That’s 16, 000 litres of water every second. This is what it looks like.
And these before and after shots demonstrate just what a difference that kind of release makes to the appearance of the river.
Before release
After (the salmon spawning pit is to the right of the picture)
Now, you’d think that this is all good news but there are some grumpy anglers who aren’t so happy. There is a specially constructed Salmon spawning bed just below the dam. It’s an impressive structure and evidence of a serious commitment to the returning Atlantic wanderers. However, last year, only two Salmon made it, leading to some speculation that pulsed releases from the dam are to blame (despite a suspension of such releases at the key point in the season). There’s no evidence for this at the moment, though efforts are being made to raise cash through the Welsh Dee Salmon Conservation Fund in order to commission research.
Whatever, it’s a stunning river in a beautiful; location. It’s full of wild brownies too so I shall almost certainly be back.