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Severn Bore by Moonlight - copyright Joan Lee (2013) |
This is a collage I did shortly
after we returned from our trip away in September, inspired by the Severn Bore I
watched towards the end of it. I used some artistic licence: on this occasion, it
wasn’t a clear, crisp moonlit night. I also drew on memories of tidal races and
Severn Bores past.
More of my artwork at Water
& Art
This night time viewing of
the bore was at the beginning of a weekend trip, based in the Forest of Dean,
organised by the Wessex Branch of the Open University Geological Society
(WOUGS). For various reasons, it’s been a while since I’ve studied anything
with the OU. The level 2 Geology Course was among the courses I did during the
2000s. Like most of their courses, it was intensive to study, but the content
was excellent. It transformed days out and holidays – since doing it I’ve
always been on the look for rocks and I still, occasionally going on some of
their trips around the UK to sites of Geological interest. On the Saturday and
Sunday (21st / 22nd September) they had field trips to
the Forest of Dean and both sides of the Severn estuary / Bristol Channel. I
did the Saturday one, see separate entries for the Upper Soudley Trail and
Severn estuary.
Leaving Chepstow, we headed
towards the Forest of Dean, taking the route my parents took during my
childhood camping holidays in the area. We crossed the River Wye, over the town
bridge, taking the B’ road onto the A48, through Lydney, Blakeney and Newnham.
There didn’t seem to be quite so many views of the Severn from
the main road as I'd seen through the rose tinted spectacles I wore during my
childhood. Frequently, it was hidden behind hedges and, at Newnham, a floodbank.
Caught glimpses, at Newnham and from some of the higher ground. Oldbury nuclear
power station was just as prominent on the far side as it’s always been.
Believe this and Berkeley just upstream are now being decommissioned, a process
which will take many decades. Don't know off-hand whether there are any plans
to replace them. From what I could see at Newnham, the low tide water level was
very low, the water there was dead calm, with birds on the sand-mud banks.
We got to the hotel around
5pm, joined the other WOUGS members for dinner at half-seven. We then headed
off to the Severn Bore Inn, on the A48, just south of Minsterworth. We arrived just before 9pm, about 35
minutes before the Bore was due – they say be there at least thirty minutes
before; tidal bores being even less punctual than buses or trains. The predicted time here was around 21:30 BST, a three star. They can go up
to four or five and exceed 2m in height. Very conveniently, there was a green
area in front of the pub car park, which we had all to ourselves, along the
banks of the Severn. Here it looked more like a river than an estuary, much
narrower. Of course, it was dark, so I wasn’t sure how much we’d actually see
of the bore. The Moon was just past full
- Full moon 19/09/13, Thursday, 12:15h BST. I’d hoped it would be out and
reflected on the water. It was for some of the time, though it was very hazy
and it kept drifting behind cloud. Light pollution from the street lights in
the car park and passing traffic on the A48 was less of an issue than when trying
to stargaze, though our view down the river was easier with when there wasn’t
any glare. The car park lighting was less noticeable standing in some places
along the river bank than others. All in all, we all twigged that we were
looking down the river towards a bend.
Before the bore, the water was remarkably calm
almost still; just a few ripples lit by the Moon as it came and went. The trees
on the far bank and in the distance along the river were reflected near
perfectly. Little or no wind and it felt very mild. I was just dressed in a
light coat. On the far bank a ribbon of white torch lights on the move. We made
out that they were runners. Probably some charity moonlit run.
Increasingly, as the predicted time approached,
we looked down the river for any signs of the wave, or waves - usually one or
more behind the leading one - and for signs of any water movement. At one
point, we thought we saw a tantalising change in the distant reflections of the
trees, only to find not. As 9.30pm came
and went, I heard people around doubting, “It’s stuck”.
“Is this the Avon, or the Gloucester &
Sharpness Canal?”
“It’s gone up a tributary”, the Wye perhaps?
Someone phoned on their mobile from Newnham, to
say it was ten minutes late there – a bit more reliable than Southern Rail can
be, then.
We heard it first: a distant roar of the kind
sea waves make when breaking on the shore, only more prolonged. Then the reflections
upriver disappeared. “Here she goes…”, someone said, shortly be we made out a
white breaking wave angled to the far bank. The mobile phone went again, just
as we saw it break on the far side, then race past us. It was hard to tell what
speed it was doing – C C.Eng arl’s estimated 10 miles per hour. It was
definitely faster than the flood tide current on the Arun. The main wave was
quickly followed by a second one, this time breaking on the nearside; though we
didn’t see it do so as it was hidden behind the rushes. We made out the rise in
water level, no longer any reflections. After the waves had passed, it felt a
bit cooler, just as it can do by the sea when the tide is in. No surfers, as
there usually are on daytime bore. After the waves had passed, the water
quickly calmed down, within minutes.
At dinner the following even one of the WOUGS
organisers said we were all “A bit impressed”, though perhaps not overwhelmed
or amazed. I regret not seeing it in daylight this year – it’s been a while.
Severn Bores Past
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Severn Bore - February 1984 |
My by best view of the bore
during daylight is still Lower Parting, near Gloucester, now nearly 30 years
ago, on a February Saturday. My secondary school geography teacher led a field
trip, beginning with an early morning start to view the bore, followed by looking
at Jurassic fossils on the Cotswold escarpment, then Aust Cliff in the
afternoon. I have a grainy photo here.
The full moon in my collage
here is more reminiscent of the night at Newnham-on-Severn, when it was clear.
This was again part of a WOUGS trip. There, where the river is much wider, it
was a fairly shallow wave of only about 30cm / 1 foot high. Some of my fellow
WOUGers were disappointed, “Is that it?”.
But there then followed a great tidal race, most of the high tide rushing in
over a period of about 30 minutes as a turbulent current. Certainly when it
came to the power of the water, I was actually more impressed by this than what
I’d seen this evening. As were staying somewhere nearby overnight (now apparently
closed down) were able to return to the river the next morning and view it in
the daylight. My other art work here – mixed media paintings – were done around
this time.
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Tidal Race (2007) - Copyright Joan Lee |
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Making Waves (2007) - Copyright Joan Lee |
Background
There aren’t tidal bores on every tide on the
Severn, just the spring tides, when the high tide at Beachley exceeds 8m, 9m
for the larger bores. The highest spring tides occur around the spring and
autumnal equinoxes. The spring tides on the Severn always occur early in the
morning or in the evening, in the dark. Not as convenient, then, as tidal gorping
closer to home. Not ideal either for anyone like us with journeys upwards of
100 miles / two hours travelling to do as a day trip. There doesn’t seem to be
much in the way of overnight accommodation within easy walking distance of the
river.
For some reason, the tides during 2013 have been
more modest than other years. There was a four star bore predicted on the night
of 22nd August. Otherwise there’s been nothing above three star.
These predictions are astronomical, taking into
account the relative positions of the Moon and the Sun, which would affect the
size of the tidal bulge due to their combined gravitational pulls on the Earth.
The predictions don’t take any account of the weather and the amount of
freshwater coming down the River Severn. When there’s high pressure over the
north Atlantic off the western coasts of the British Isles, the bore / tide
height will be lower; higher if a low pressure system over the same area. I’d
have thought, after the end of a fairly dry spring and summer, the freshwater
of the Severn would be fairly low.
It runs faster (10-13 miles per hour / 16 – 21 km/h
in the narrower river between Gloucester and Minsterworth than in the wider
sandy estuary around Newnham - 8-13 km/h (5 – 8 miles per hour).
References and Links
Open University Geological
Society homepage
Wessex branch
1.Alan Holiday, The Severn Bore, Soudley, Beachley
Point and Sedbury Cliff, Open University Geological Society Wessex Branch
field trip handout (2013).
Severn Bore timetable 2013
Wikipedia – Severn Bore
Severn Bore Facts
Macho Bore website for surfing dudes