After returning from a walk this afternoon across Leyton Marshes and onto the Lower Lea it is quite apparent how much it has rained in England this winter. Last Friday the Lea was at its highest level I have witnessed in many years, today it was still very high but had dropped about a metre, the marsh was flooded but that is usual for this time of year. The simple truth is global warming has changed the British weather and this is going to affect our rivers especially if our current selection of politicians make the final environmental decisions.
I did promise to myself not to get political here so I will refrain but I will say one thing, our stand-in Flood Minister Eric Pickles is a misinformed fool and I fear that he will cause so much environmental damage to our rivers that it could take a generation before they are rectified, long after Mr Pickles has left his post. ‘Dredging’ is a word that has been thrown about over the last couple of months as the answer to the flooding problems, is it? I’m really not convinced and nor are the true experts out there, dredging seems a nice quick solution and makes the government look like they are doing something, great but I believe it is the wrong action to take?
Now the science bit. I’m no expert but using the River Parrett as an example, if you dredge the whole length the silt would equate to 2-3% in volume of the amount of standing water in the locally affected area, so you would still have 97-98% of the water left. So dredging must be more about flow and not volume? If this is the case then the entire length of the river (37miles) would have to be dredged to avoid bottle necks down stream and the potential flooding of towns like Bridgewater and Dunball. I imagine dredging 37 miles of river would cost millions and be devastating to the landscape. Finally, would this not cause a fast flowing and dangerous relief channel?
As I said at the start, there are dark days ahead for our rivers and their inhabitants which will last long after the current rabble of politicians have gone. It is a very depressing thought and I can’t see dredging is the answer unless someone can explain to me the science rather than simply expressing the frustration.
In the meantime a flooded landscape in its splendour…
Update: Thanks to a certain Mole I came across this and discovered two things, one there appears to be a hydrological community and two, they seem to know what they are talking about, see here