London scoping - ukcip

Final Report
170
that a significant proportion of London lies within the floodplain of the River Thames and its
tributaries.
The UK is unusual in that flood insurance is currently offered as standard with buildings and
contents policies. Property damage as a result of river, and other sources of, flooding is covered
to some degree for almost all insured properties in the UK. Thus, the higher rainfall incidence
predicted for the UK by the London and UKCIP02 climate scenarios is likely to result in an
increased value of claims against the insurance industry. A recent analogue of this type of event
were the floods of Autumn 2000. In this case, 12,000 properties were damaged and a further
37,000 properties were classed as ‘near misses’ by the Environment Agency. The total cost for
the UK insurance industry to date is over £1.0 billion.
The causes of flood risk are not confined to tidal or river flooding. Other particular concerns for
London include:
The large size of urban catchments;
The rate of development of new housing and associated development in the main
drainage tributary systems;
Particular hazard of short duration, intense storms on the drainage systems (foul
and storm);
The ageing condition and lack of capacity of existing drainage systems;
Impact of rising groundwater in conjunction with surface flooding.
Even new drainage systems are designed to cope only with normal rainfall levels. Recent
research has shown that climate change will mean that many of these systems will surcharge
several times a year in the future (Futter and Lang, 2001). Stakeholders hope that the threat of
this flood risk will be reduced by the Sustainable Urban Drainage Systems (SUDS) initiative
promoted by the Environment Agency and the Scottish Environment Protection Agency which
aims to promote good practice in the construction of robust drainage systems with sufficient
capacity to cope with rainfall events foreseen by the London climate change scenarios.
Exposure to River Flood Risk and Adaptation Strategies
A number of adaptation options for reducing flood risks likely to arise from climate change in
London are outlined in Section 5 and the section on water resources in this section, above. In
the following paragraphs an insurance industry perspective on the current development of flood
prevention strategies is presented.
7.5.3 Temperature Change Impacts
Palutikof (nbu.ac.uk web-site) points out that freezing weather causes damage even in a
relatively mild winter, when a short episode of very cold temperatures can cause substantial
claims for burst-pipe damage. Also householders are more likely to take a winter holiday,
leaving the house empty and unheated. The balance of opinion in the industry suggests that
these two factors more or less cancel in the present climate. Potential claims from this type of
weather event are significant for the industry (though less than flood and storm costs): it is
estimated that £250 million of claims resulted from such an event in 1996 in the UK. This type