Barry Greenwood says (‘Main waterways must be dredged’, November 13) “I have researched the benefits and disadvantages of dredging and maintaining the rivers, streams, dams etc in order to obtain a better understanding of the objections raised against maintenance and dredging”.
But so have the Environment Agency and the conclusion they reached, based upon expert scientific computer modelling of the river channel at Mytholmroyd, is that managing and clearing vegetation on the river banks is much more effective at that particular location in reducing flood risk: ‘the impact of dredging reduces water levels by 1-2 inches whereas managing vegetation reduces water levels by 1-1.3 feet.”
This is because a large volume of vegetation holds up the water flow, causing it to overtop defences. Anybody can read their report which is available on the Calder Future website www.calderfuture.org.uk.
Calder Future found this modelling credible and convincing and on that basis, and at the request of the EA and Calderdale Council, carried out a systematic programme of reducing vegetation levels on the riverbanks in Mytholmroyd town centre. We thank the many volunteers – including four big teams from Lloyds Banking Group – who did this work.
Of course vegetation management on its own is not enough. At the same time the council and the EA’s comprehensive approach involves clearing gullies and outflows, and preparing a programme of flood risk reduction schemes of various sizes as well as investigating the possibility of a larger flood alleviation scheme for Mytholmroyd.
It’s this package as a whole which will give the town a better chance of avoiding or lessening future flooding.
Let’s be clear, this only brings a reduction, not an elimination of flood risk; and flood water comes not just from the river but also from the hills above. With the Met Office apparently now forecasting the ‘wettest winter since 1981’ everyone in the Upper Calder Valley will be in some trepidation about what the next months may bring.
But simply repeating that ‘only dredging is the answer’, when the evidence for Mytholmroyd does not support that claim, will not help the community understand and then respond to the complexity of flood risk in the best ways possible.
(Chair, Calder Future)