Question to the Department for Environment, Food and Rural Affairs:

To ask His Majesty's Government what is the life expectancy of the Thames Barrier; and whether there are any plans to alter the current pattern or frequency of use in order to manage its expected lifespan.

The Thames Barrier forms part of a complex system of assets along the Thames and its tributaries to manage the risk of flooding in London. The barrier is expected to provide the required standard of protection out to 2070 based on projected rates of sea levels rise and with significant investment to upgrade and improve the mechanical, electrical, forecasting and supporting systems.

The Thames Barrier needs to be maintained to ensure its operational reliability. Closing it too frequently could reduce its reliability, because it would make it difficult to maintain to the required standards, as well as negatively impacting on shipping. As such the Thames Estuary 2100 Plan sets out a strategy to manage the frequency of closures and its lifespan. This includes implementing measures to manage non-tidal flooding (i.e., flooding driven by high river flows coming down the Thames) in west London without relying on the Thames Barrier by 2035, as well as raising defences upstream of the barrier by 2050 to allow higher tides upriver, thereby reducing the number of times the barrier needs to close.

The Thames Estuary Plan takes an adaptation pathways approach, planning for a range of future climate scenarios with a light touch review every five years and a comprehensive review every 10 years. At present all end of century options for upgrading or replacing the Thames Barrier remain available, with a decision needed by 2040 so that an option can be in place by 2070.