From puddles to the sea
Reviewer: Elizabeth Rogers
THE water of a river is much more than an expanse running between two banks; there is much more we can learn from and about the nature of it, and the man to tell us how to do so is Tristan Gooley.
He is a global authority on natural navigation and a renowned expedition leader, but his fascinating description of the ‘Clues, Signs and Patterns from Puddles to the Sea’ – the sub-title of the book How to Read Water – covers not just the far-flung places of the world but countryside much nearer home.
The section on rivers tells how both the surrounding landscape conditions and the wildlife on and beside it can inform of the likelihood of flooding following heavy rains.
If a river flows through a terrain of impervious rock and soils, such as clay, the rainfall will follow a path to a watercourse as it cannot be absorbed quickly into the ground. If it flows through a terrain of chalk or limestone it can sink into the ground and become part of the water table.
A way to judge which the ‘flashy’ rivers that will flood are, he says, to look for those with a high bridge supported by tall pillars, built to accommodate high waters.
A clue to a surrounding chalk or limestone landscape is in one of the creatures of the rivers; as crayfish need plenty of calcium to build up their shells, they are found in watercourses in chalk or limestone countryside.
Other creatures have preferences; the dipper, a small mainly dark bird but with a bright/white chest and throat, is found only in or near fast-flowing water, as are the grey wagtail, red-breasted merganser and the common sandpiper. Those found on the slower-moving waters of lowland rivers include the coot, mute swan, moorhen, goose and cormorant.
Many of the clues and patterns covered have important scientific implications, but on a lighter note the author tells how he taught his sons the best way to win at the game of ‘pooh sticks.’ He pointed out to them that the waters run fastest in the deeper centre of a river, not being slowed by contact with the banks and a more shallow flow.
And the puddles? Even they have information to give. Their sudden appearance on a pathway dry until that point indicates a change of terrain from porous to impervious rock.
How to Read Water by Tristan Gooley is published by Hodder and Stoughton, hardback, 376 pages, price £20.