Monday 10 February 2014

Somerset levels - yet more!

8 February 2014

I listened to an interview with Ian Liddell-Grainger this morning concerning the flooding and response to flooding. I was amazed to hear him say that dredging would help to resolve the problem because it would allow pumping at high tide.

Who on earth provides this advice? Dredging is highly unlikely to lead to a significant reduction in high tide levels and is most likely to lead to increased tidal propagation (as per my previous post). The trouble is that once high-profile people make these sorts of comments it becomes accepted fact and the message of incompetence on the part of river managers gets even more embedded.

I begin to feel that it is time to give up a technical profession as we are seeing an increasing failure amongst politicians to make sure that they genuinely understand technical issues.

There is a need to look very carefully at the ways in which key landscape management issues are presented. For many years I have held the view (and even said as much - see links below) that the biggest problem with sensible adaptation measures is that they are promoted by nature conservationists who arguably present this as a wildlife gain. I think there is a need to re-think this approach and to develop a way of promoting certain types of management from more of an engineering and socio-economic angle. That means re-education in various places.

Thus, in the case of water management, I would highlight the following as critical areas:

  • Blanket bog regeneration 
  • Upland re-wildling using native species
  • Managed realignment
  • Creation of washlands
  • Sediment husbandry

In this respect, there is also an urgent need to look at the cost-benefit of such measures in a much longer time-frame. At the moment headline costs of a managed realignment can be presented as wasting XX million pounds for a 'bird sanctuary' but in fact the real engineering benefits may be felt over decades and may even have a bearing on resilience well beyond the lifetime of current generations.

Hopefully this period of extreme weather will get somebody thinking sensibly. The danger is that all the sensible adaptation measures will be thrown out as the ideas of intellectuals and that the real answer is to dredge deeper and build increasingly larger defences. The problems at Dawlish seem to me to be an exemplar - if the final decision is to invest on the existing route then future generations will be inheriting the results of our folly compounding the arrogance of the engineers who first placed the railway on an eroding coastline!

Useful links
http://www.bacoastal.co.uk/Papers/2012-CEDA-seminar-presentation.pdf
http://www.bacoastal.co.uk/Papers/2011-CCCR-Presentation.pdf
http://www.bacoastal.co.uk/Papers/2011-ECSA-Managed-realignment-presentation.pdf

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