London scoping - ukcip

As a consequence:
Final Report
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"the flood defence standard is about 1:2000 years or 0.05% risk of flooding.
With sea level rise this will gradually decline, as planned, to a 1:1000 year or
0.1% risk of flooding by the year 2030. Thereafter, if improvements are not
made the defence standard will continue to fall. Preliminary estimates of the
cost of providing 0.1% standard to the year 2100 show that a major investment
in the flood defences infrastructure of the order of £4bn may be required within
the next 40 years" (Environment Agency 2002).
The standard of flood protection of the Thames in London is high. Low-lying areas targeted by
development plans for the Thames Gateway (Barking, Havering, Erith, etc.) are currently wellprotected
against the risk of flooding; nevertheless the risk does need to be recognised. Clearly,
a 0.05% risk is relatively low and a higher standard of protection is applied to the Thames than
that which is usually applied to riverine (1%) or estuarine & coastal (0.5%) flood protection in
the UK. The residual risk of an extremely serious flood event overtopping or breaching the
defences of course remains. Much of the development land in the Thames Gateway will
consist of brownfield sites, and such land is frequently to be found in the flood plain. Many
brownfield sites have been used for industrial purposes. The ABI notes that the vulnerability of
housing and retail property to flood damage may be far greater than for many industrial uses
because of the greater value of the assets exposed (ABI 2002).
It should be noted, nevertheless, that the economic and social costs of a 1 in 2000 year event
(the level of protection which existing flood defences are currently estimated to provide) are
likely to be highly significant for the local, national and international economies. The most
significant of these costs are thought to be:
Repair to private property – to be met by the household/business and/or insurance
agents;
Repair to public property – to be met by local and/or national taxpayer;
Relocation costs of household, business and public administration;
Preventative expenditures associated with building design that reduce flood risk
further – to be met by developer/occupier (private property) or taxpayer (local
authority-owned);
Disruption to transport infrastructure and subsequent repairs.
There may also be an impact on the attractiveness of the London property market to overseas
investors, and more generally, the attractiveness of the city as a place to conduct business of all
sorts. These potential indirect effects have not been quantified but are clearly likely to be a
major factor in the economic appraisal of future investments in flood prevention measures.
Related to this, a greater perceived flood risk along the Thames corridor may result in reluctance
of businesses and households to live and work in at-risk areas. This type of economic blight
may cause those who can afford to relocate to move to other areas of London or outside of
London. These effects will cause land prices to rise in other parts of London and result in
occupation of the blighted areas only by low-income groups.
A further important issue relating to the nature of economic development in London is the
knock-on impacts of riverside development in East London in the next decade upon the