14th August, 2017  As the water entering the drain seems to go into the pipe I imagine there's a break in the pipe; an outer part was probably connected to an inner and has been dislodged by the falling tree. Water now flows around the pipe and constitutes the larger part of the flow once water has receded to a degree. It's hard to know without getting down and dirty with some risk

June 4th 2016 I had cleared a path along the bund some week ago, thinking I had reached the Japanese Knotweed patch; today I realised the landscape had changed. A large tree in the bund had fallen into the river damaging the bund and drain. Subsequent tides have washed away a substantial part of the bund adding to my disorientation.

Looking at top of the bund

Fallen Tree
Note by 2017 96% of the Himalayan balsam visible has been washed away.

Looking from bund down to the drain.
Previously the drain was within the bund.

Next page pics from 2017

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