§ Bob SpinkTo ask the Secretary of State for Environment, Food and Rural Affairs what estimate she has made of the possible rise in sea level in the Thames Estuary as a result of(a) climate change and (b) other 1768W factors in the next (i) 25, (ii) 50 and (iii) 75 year terms; and what research her Department has (A) carried out and (B) commissioned into the subject. [154230]
§ Mr. MorleyThe Thames Barrier was originally constructed to accommodate an 8mm per year increase in sea level, which at the time of design was extrapolated from tidal records through the Estuary. This, in principle, provides protection against a one in a 1000 year tidal surge up to 2030. Current guidance from DEFRA suggests an increase in relative sea level of up to 6mm per year is built into plans for future flood defences.
The 6mm per year figure is intended to accommodate the impact of climate change on sea level; that is thermal expansion of the oceans and ice melt of coastal ice-sheets, as well as long-term regional land subsidence.
Currently the Environment Agency is undertaking work to consider flood risk management options for the estuary up until 2100 under the project, Thames Estuary 2100. This will also involve making a full assessment of the risks associated with climate induced sea level, including potential changes in North Sea surges.
Predictions for the next 100 years will be developed using UK Climate Impact Programme research combined with trends inferred from the project's investigation into absolute ground level changes. This research is currently scheduled to be completed by September 2006.