Retain water upstream
To prevent flooding downstream, we must retain water upstream, or at the very least, slow the rate of flow.
Since early December, there has been bad flooding across the country, in Gloucestershire, water as far as the eye can see.
News reports have people calling for better flood defences, dredging, clearing streams of debris.
Dredging, clearing steams of debris, simply sends the water faster downstream, causing worse flooding downstream.
We need to slow the flow of water from upstream, encourage the absorption of water.
A news report on the BBC last week, had just that, slowing the flow of water upstream, by felling trees into the streams.
As George Monmbiot reports in Feral, the Yorkshire town of Pickering used to regularly flood, until they reversed the programme of clearing debris from steams, and instead, felled trees into the streams. But, as George Monbiot asks, what happens when the money for this programme runs out?
On the BBC news story, they highlighted the difficulty of raising the money for these uphill programmes, and yet it is a fraction of the money required for downhill flood prevention.
A similar programme in the Wye valley.
The debris in the streams, increases the diversity of wildlife habitats.
But why not go further, let us introduce beavers.
Beavers cut down trees, damn the streams, slow the water flow, create small habitats, clean up the water of the stream. And contrary to the nonsense from landowners, or those with fishing rights, beavers by improving the river quality, improve the rivers for salmon.
Our uplands are bare, over-grazed by sheep and deer, burnt for grouse. The soil, where there is soil, is compacted. This leads to rapid water run off.
We need to eliminate or at least reduce, the sheep and deer by the introduction of wolves.
Where areas adjacent to the remnants of the Old Caledonian Forest have been fenced off, the trees are recovering.
If we re-afforest the uploads, we will greatly reduce the run off, allow the water to recharge underground aquifers.
Following weeks of heavy rain and very heavy overnight rain, the River Wey in Guildford last Friday was running very fast and high, within inches of overflowing and flooding the road. The bottom end of the town has already been flooded this winter.
In Farnham, on Saturday, the River Wey was running high and fast, but not overflowing its banks. Parts of Bishop’s Meadow were flooded, but this appeared to be due to water coming down from the town, not the river overflowing.
Were it not for local people forming a Trust, and buying Bishop’s Meadow, a flood meadow, it was earmarked for housing.
The River Wey, from Godalming downstream, is a navigable waterway. Flood meadows upstream of Guildford can be flooded by opening sluice gates to protect the town, but even this was not sufficient to prevent the town from flooding.
We need to look where water is coming from upstream, the land draining into the streams, and do what we can to ensure the water flow is slowed and the land absorbs the water.
Slowing the water flow, recharges underground aquifers, helps to prevent droughts in the summer.
The River Wey rises in springs in Alton. Summer 2012, the springs dried up and the river bed was dry.
Cove Brook rises on Caesar’s Camp. There is a leat that collects the water run off, feeds it into a reservoir. When I walked along the leat last summer, or tried to, it had fallen into disrepair. Cove Brook flows through Farnborough Airport. Drainage was installed, to speed the flow downstream. During heavy rainfall, Cove Brook turns into a raging torrent. Southwood Golf Course, on a flood plain, turns into one huge lake. There were plans to install drainage, but fortunately blocked, as this would simply have flooded downstream.
We have to rewild, let Nature takes its course, recognise flood plains are for flooding, reintroduce beavers, wild boars, wolves.
With coastal areas, the problem is different, it is not water upstream, estuaries being the exception, it is inundation by rising sea levels. We have to be prepared to abandon parts of the coast to salt marshes.
We also have to allow areas like the Somerset Levels to flood.
