Thanks to Dave Maynard for some striking photos of the landscape on the flanks of Llysyfran Lake, as it is now called. The reservoir was commissioned in 1972, with the purpose of supplying cooling water in vast quantities to the old Pembroke Power Station and to the oil refineries around Milford Haven. The surface area is supposed to be 212 acres, but that is now significantly reduced.
I don't know that the water level has ever been as low as this since the first filling of the reservoir. it was low on my last visit a few months ago, and it's now even lower, in spite of a few rainy spells in the past few weeks.
Anyway, we now see submerged landscapes emerging from the water, and you can walk around the flanks of the reservoir across areas normally deeply submerged. Some of the side creeks are completely dry, and the drought has now continued for so long that previously barren submerged areas are being re-vegetated. A lot of the surface has been "washed" by wave sapping processes as water levels have oscillated in the past. As we would expect, most of the surfaces have the appearance of washed slope breccia or broken bedrock, but there are some isolated erratics and some areas that appear to be made of till, with clusters of erratic boulders. Some look as if they are igneous.
Dave has been looking for burnt mounds, of which there are several, quite well preserved and "cleaned up" by wave sapping.
If anything, the level of water is lower now than the time those drone photos were taken. The lower surfaces have a dried-out appearance, while the drone photos look as if it had been recently raining.
ReplyDeleteDid you make a note from the level guage, Dave, of how many metres the water level has dropped from the overspill level?
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