Shoreline Management Plans Based On Fake Sea Level Rise Projections

By Paul Homewood

h/t Jon Seward

 

 

 

Happisburgh

In the United Kingdom, responsibilities for planning and managing the risks associated with coastal flooding and erosion are a bit of a mish mash, with DEFRA, the Environment Agency and local authorities all involved, usually on a non-statutory basis. Nevertheless there is a presumption that coastal communities cannot be protected at any cost. As The EA’s James Bevan proclaimed last year:

“Climate change is happening now, and its impacts will continue to worsen. Rainfall patterns are changing, causing more frequent flooding, and while we continue to protect and prepare coastal communities from rising sea levels, it is inevitable that at some point some of our communities will have to move back from the coast”

The reality is that this has always been the case of course!

In England, the Flood and Water Management Act 2010 set out the requirement for a national framework for managing risk to be issued by the national environmental regulator, the Environment Agency. The current version of this framework has been set out in “Understanding the risks, empowering communities, building resilience: The national flood and coastal erosion risk management strategy for England” (Environment Agency, 2011). This sets out a high-level framework which empowers various actors to plan for and manage risk, including future pressures such as sea-level rise (SLR).

The key vehicle for strategic planning of coastal erosion risks in England has been the shoreline management plan (SMP). This is overseen by a coastal erosion risk management authority, a local authority whose functions include planning shoreline management activities with input from the Environment Agency and the delivery of coastal erosion risk management activities (using powers under a range of legislation). The SMP is a local strategic plan put together by groups of key stakeholders in defined coastal areas. First-generation plans were issued in 1996, and the current second-generation plans were generally completed in 2009. The SMPs take account of future projections of SLR driven by climate change.

Pay particular attention to that last sentence – the SMPs take account of future projections of SLR driven by climate change.

In 2012, a Shoreline Management Plan (SMP) was drawn up for the Norfolk coastline by a group including the EA and local councils:

https://www.eastangliacoastalgroup.org/smp-6

The SMP recognised the historical perspective, and stated that no coastal defences can stop these natural processes, merely delay them:

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Nevertheless, coastal defences can play a valuable short term role, but it is then a matter of cost:

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Note that they assume that the cost of maintaining existing defences is forecast to rise significantly. This of course then affects the cost/benefit ratio of any scheme.

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I should point out at this stage that it is about a lot more then money. For instance, sediment from erosion from places like Happisburgh is to a large extent swept to other areas of the coast, such as Sheringham, Cromer and Great Yarmouth. (It is probably no coincidence that these towns have developed over the years).

So it would make no sense saving a few houses in Happisburgh, if it was at the expense of Sheringham, something the plan emphasises. Moreover messing with nature often has unexpected consequences – in Happisburgh’s case, the development of a promontory, which could interrupt the transfer of sediment and push it offshore:

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Nevertheless, the economic decisions ultimately come down to costs and benefits.

The costs are expected to rise sharply because of the projected sea level rise, meaning that bigger defences must be built.

And the SMP tells us exactly what that projection is:

The plan notes that the Table also includes the Defra 2003 recommendation for consideration of sea level rise, which has been used in the SMP assessments. In other words, 6mm/year.

But this figure clearly is not credible, given that sea levels in the region have been rising at less than half that rate, and with no acceleration. Indeed since the SMP was written in 2012, sea levels at Lowestoft have risen at only 1.0mm/year.

If a realistic sea level rise had been factored in, would the SMP recommendations have been any different. I don’t know.

But the residents of Happisburgh and all those other communities along the Norfolk coastline deserve to be told.

FOOTNOTE

To put the scale of the problem into perspective, along the whole of the coastline between Kelling to Lowestoft, basically all of the Norfolk coast and part of Suffolk, the plan reckons that the number of housing losses by 2055 could be between 80 and 1000.

Given the faulty sea level assumptions, the likely figure is at the bottom end.

Assuming 80 homes, and at say £200,000 a house, residents could be moved into new homes a few miles inland for a cost of £16 million, spread over a decade or two. I suspect that would be a lot cheaper than playing at King Canute!