Wednesday, 8 April 2015

Flood Hype and Vested Interest

“a collective myopia and lack of critique driven by an inherent satisfaction that the results show a level of risk that attracts strong and widespread public, political and financial support”
Edmund C. Penning-Rowsell
February 2014

Posted here are significant extracts from an article in "Circulation", the newsletter of the British Hydrologicaol Society. (See Appendix A, Note 1). 


.. annual average economic fluvial and coastal flood damage over the last two decades or so - a period seeing several large flood events - had not amounted to more than circa £0.25 billion (see Appendix A, Note 3).

.. many commentators, including government ministers, the Environment Agency and their officials, have continued in the last five years to emphasise that this annual loss .. exceeds £1 billion, fundamentally based on the NAFRA type assessments of flood risk that have been undertaken since 2002 .. As recently as 2012 the Climate Change Risk Assessment report on flooding and coastal erosion concluded that “Annual damage to properties due to flooding: between £1.7 and £4.5 billion by the 2050s, rising to between £2.1 and £6.2 billion by the 2080s (current figure: £1.2 billion)” .. The four-to-five-fold exaggeration .. does not sit well with the government’s commitment to good evidence based decision making .. Policy makers .. should refrain from referring to levels of... risk that are at best questionable and at worst quite simply erroneous” ..

It is instructive to update the analysis to the year 2014 .. using residential flood insurance claims .. to extrapolate to the likely overall total of both residential and non-residential losses .. indicating that the years 2012 and 2013/14 are indeed above the average for the last 16 years, but that the mean of £0.146 billion is actually lower than the mean for the years 1998 to 2010 .. This is because the year 2011 saw relatively few floods, although 8,000 properties made claims, yielding a total flood insured loss of no more than £52 million

.. The fraction of the total losses that are represented by this (residential) sector is not without significant uncertainty and variation. Results for the 2000 flooding show this fraction to be approximately 45.2%, whereas those for the 2007 floods gave a result of 37.9% .. For the 2013/14 event .. out of a total of £0.425 bn claims .. some £0.276 bn was for domestic cover .. yielding a 64.9% fraction for residential losses.
Weighting the three results by the size of the total losses in each case gives an average a figure of 41.8% for the residential fraction of total losses. If we apply this average .. and deducting the element attributable to Scotland (15.5%), we get total annual average loss/compensation of c.£0.294bn.

.. this is less than one quarter of the figure quoted by the report on the Climate Change Risk Assessment, simply because the average for 2010-14 is almost identical to the average of the previous 16 years.

The reasons for the discrepancy between NAFRA results and recorded flood losses are not clear, but probably partly reflect the flood spreading model .. which appears significantly to overpredict flood depths. In addition there are doubts about the fragility curves used to assess the chance of the failure of flood defences, which in reality are very rare in the UK. Both need investigation in a radical review of the NAFRA methodology and its data sources ..

So what do the floods of 2013/14 tell us? Despite their apparent severity, financial losses were not massive, at
£0.425bn plus £22m for motor vehicle losses .. There is therefore no new evidence here that national Annual Average Damages is anywhere near the figures of up to £1.2bn coming from NAFRA. .. the exaggerated and politically ‘embedded’ erroneous annual average flood loss figures remain a major cause for concern.

.. perhaps all those assessing risks at a national or even a regional scale have brought biases to that assessment in terms of generating a perception of high and increasing risk that is beneficial to them in their seeking to attract funding or attention. Government departments assemble information for their three-yearly Comprehensive Spending Reviews that determine their budgets going forward. The Environment Agency, supported by the ABI, has the same motivation, in seeking from Defra the maximum level of grant-in-aid, not least to help fund its general overhead. The ABI themselves have no incentive to minimise potential flood losses; indeed the reverse is the case. Similarly, researchers seek a climate of opinion that favours their efforts and the grants and contracts that provide their income and are one of the key drivers of their performance. Local organisations, pressure groups and other ‘stakeholders’ have no incentives for rigorous objectivity or to contest national assessments into which their local problems are nested.

The situation, to date, is therefore akin to a conspiracy to exaggerate, fuelled by an upward spiral of expectations of future risks that have generated the substantial increases in all flood-related budgets that have occurred over the last decade or so. It is not a real conspiracy, in that there is little actual conspiring, but it resembles a collective myopia and lack of critique driven by an inherent satisfaction that the results show (or purport to show) a level of risk that attracts strong and widespread public, political and financial support. In my view, this is distinctly unsatisfactory.



1) Circulation No. 121 February 2014 "What do the 2013/14 floods tell us about overall flood risk in England and Wales?" ( by Professor Edmund C. Penning-Rowsell (see Note 2). Reference should be made to the article for the full context and references.

2) Edmund C. Penning-Rowsell, BSc. MA. PhD. is Pro Vice-Chancellor for Research at Middlesex University. He was Professor of Geography at the University's Flood Hazard Research Centre (FHRC) which he founded in 1970 and was Head of the Centre until February 2010. Professor Penning-Rowsell was Chair of the Defra/Environment Agency Advisory Group on Flood and Coastal Defence Research and Development (2004/5), and is currently a member of the Defra/ Environment Agency Research Sponsoring Board. He was awarded the O.B.E. by the Queen for services to flood risk management in May 2006 ( Professor Penning-Rowsell is a highly respected researcher specialising in flood hazards who has authored numerous books and articles on the subject.

3) The referenced 2014 paper by Professor Penning-Rowsell requires a small correction to the figure of £0.268bn in Table IV of that paper, which should be £0.322bn (to correct for insurance penetration). This does not affect the final (£0.25bn) average when given to 2 significant figures.

NB: This note does not appear at this point in the Circulation article however it does appear at the foot of page 3.

4) There is an excellent picture of a flooded Burrowbridge, located at the confluence of the rivers Parrett and Tone (and the old course of the Cary) on the Somerset Levels, SW England, taken in February 2014. The centreground shows the ruins of St. Michael's Church atop Burrow Mump (hill) rising out of the low-lying Levels. Archaeologists from English Heritage advise that " .. The sides of the mound appear to have been terraced in the medieval period for cultivation, possibly because dry land was at a premium at the time .. The majority of the land in the Levels lies below the high water mark, so in constant danger of flooding .. " (

Another of the interesting comments in that English Heritage report is " .. This process of drainage and reclamation may have led to changes in the settlement pattern in the medieval period. The deserted farmsteads identified in the survey area to the south and east of Othery (PRNs 11276 and 54919) and to the west of Thorngrove (PRN 11272) and the deserted hamlet to the south of Burrowbridge (PRN 44296) may be examples of incursions onto reclaimed land in the moor, possibly later abandoned due to flooding .. ".
The source of the header picture (and others) of the February 2014 flooding around Burrowbridge, Somerset,is 

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