Thoughts on OFAS

Why do we need a flood scheme at all?

We have had five major floods since 2000 and climate change will make things worse (indeed there is evidence from Oxford University that it already has). Oxford residents, and the economic well-being of the City, will suffer badly if something is not done. While the scheme will cause disruption during its construction it is imperative that Oxford is protected.

But what about downstream, won’t they be worse off?

All the detailed computer modelling for the Scheme (and we have recently heard on the grapevine that a totally independent consultancy has confirmed this ) says that flooding will not be made worse downstream. We know that comparisons are made with the Jubilee River – this scheme is nothing like that. Indeed OFAS is actually increasing the capacity of the floodplain, which together with bunding and rerouting of flow will reduce flood risk to many hundreds of properties.

Is it a concrete channel?

No, it isn’t. What it is is a much more naturalistic 2-stage channel, used around the world for flood relief.

How will the environment be affected?

While there will, regrettably, be some environmental losses, we are pressing hard – collaborating with the Environment Agency, and with support from others, particularly the Freshwater Habitats Trust – for environmental enhancements as part of the scheme. While one cannot compare one environmental loss directly with another environmental gain we believe the positives will be considerable.

Maintenance.

It’s so important that there is a plan now for the very long-term maintenance of the Scheme. In our experience over the last 10 years  “if maintenance can be neglected it probably will be”. There are some honourable exceptions and we certainly have we have no criticism whatever of the local EA maintenance team, who achieve a huge amount with very limited resources. Others do nothing or very little unless goaded and embarrassed into action. This Scheme, being “natural” will deteriorate quickly if not proactively maintained. The initial intent was to plan maintenance for 10 years: that is simply not good enough for such an expensive and important project. We have proposed that maintenance be planned for in perpetuity by setting up a responsible, funded, local body, maybe as a charitable trust (or similar).

A Green group

thinks that Oxford could and should be protected by very different means – while they are short on specifics, their main idea seems to be that planting enough trees upstream in the Cotswolds would solve Oxford’s problems. It wouldn’t. Expert opinion at our 2015 Symposium of Natural Flood Management (NFM)  made that very clear. Even afforesting the whole of the Cotswolds (not that that would ever happen) would not do the job. Oxford is simply too far downstream for that. That’s not to say that NFM can’t work in smaller catchments, nor that it might not make a contribution.

Flooding land upstream?

The Environment Agency’s Oxford Flood Risk Management Strategy (OFRMS) suggests this may be needed one day if climate change makes things sufficiently bad. Involving as it would temporary flooding large areas of farmland and other land it is never likely to be easy to implement.

 

 

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