Graigwen
Active member
Very heavy rain two or three times a year in the Blaenavon, Varteg and Pwll Du areas causes the free air surface in Lein Fawr (the main conduit taking water from Rifleman's Chamber in Ogof Draenen) to migrate upstream from somewhere near Snatchwood Risings to above Abersychan. This results in water pouring up out of Charlotte's Estavelle in the "Bouncing Field" at Abersychan inconveniencing her horses. The water flows at first along a shallow channel into the nearby Afon Lwyd.
As the underground water level falls, the free air surface moves downstream again and water from the flooded field pours back into the estavelle, so the flooded area drains very quickly.
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As the underground water level falls, the free air surface moves downstream again and water from the flooded field pours back into the estavelle, so the flooded area drains very quickly.
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