Study Shows Reforestation Helps Prevent Flooding

Flooded Broadway underpass, Belfast city

Heavy flooding over the Christmas and new year period has affected many areas of Ireland, devastating homes,farms, businesses and roads.  Looking for solutions, commentators and politicians in Ireland have suggested dredging rivers and ecosystems.  But such dredging can potentially affect properties and urban centres downstream.

This article by Andrew St Ledger of The Woodland League points out the huge role planting native trees can play in the reduction of threats caused by flooding.

Via Irish Examiner:

We can all agree that we are in desperate need of wise flood-prevention measures that work.

This is a long-running problem — to quote the Chinese emperor Yu, 3,160 years ago whose ancient proverb reminds us, “To protect your rivers, first protect your mountains”.

Within only a few weeks of the conclusion of the Paris Climate Conference — COP 21, many of our lowland towns have experienced extensive flooding. The cause may lie partly with climate change, but one solution to the flooding is much nearer home: In our uplands, where the wrong species of tree and forestry model have been chosen for decades. What is needed on appropriate selected sites in the uplands are native, deep-rooted trees, planted with a view to flood alleviation, soil protection, carbon uptake, small farm viability, and biodiversity — rather than quick profit for the few, which those downstream end up paying for.

Native woodlands in uplands reduce the effects of flooding. This is proven by recent scientific research such as the Pontbren Project, by Bangor University in Wales. They examined the management of upland sites by a group of farmers. It established that soil under mixed native trees absorbs water 67 times faster than under grass: Native trees have such deep roots that they provide channels to send the water much further underground. The soil under native trees acts as a sponge — a reservoir — which sucks in water, then releases it slowly.

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