More of this...

"These five trees have been planted to reduce the amount and speed of water entering the drains.

Surface water from the highway is channelled into the tree pits and circulated through perforated pipes, distributing water to the roots so that it can be absorbed by the tree as it grows.

Permeable surfaces allow water to soak through the ground to the roots.

Rainfall is intercepted by the leaves and branches slowing down the flow of water. This helps to prevent surface water flooding. 

Any water not used by the trees returns to the highway drainage, cleansed by the tree pit."

More of this. Much more of this.

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Reading: 'Jews Don't Count' by David Baddiel