The physical causes consist of:
-
Tidal and river surges these may be more sever then the ones face to regally.
- Consurge may occur at certain water levels.
- Threat of heavy rains is also high, there can be fluvial and tracheal rain.
- Typical; spring tide can raise levels by up to 6 meters which in turn means up to 100 squared kilometres of London is bellow the high tide level.
These to factors the first human and the second physical:
- Significant impact of sea level rise due to climate change
- The south-eastern tip of the Thames region is ‘sinking’ back to pre ice age levels.
Both contribute to increasing tidal behaviour above previous ordinance survey Newlyn; causing greater chances of overwhelming defences. Climate scenarios carry a large amount of uncertainties great variations exist when forecasting. Green house gas emissions are easily measured, but radioactive forcing; climate sensitivity and time-lag cause uncertainties thus affecting investment decisions. This rise could be 90cm under highest emissions scenarios. More alarming “not implausible” events e.g. sudden collapse of the west Antarctic ice sheet could produce 5 meters rise by 2125 leaving London with 3 drastic options:
- Protection (building an outer barrier)
- Abandoning
- Reshaping
I believe there are 3 main solutions to prevent flooding in the future:
- Raise the Thames Barrier.
- Stop building on the Thames Gateway
- Design flood proof buildings.
Raise the Thames Barrier
The Thames Barrier is one of the largest movable flood barriers in the world. The Environment Agency runs and maintains the Thames Barrier as well as the capital’s other flood defences.
The barrier spans 520 metres across the River Thames near Woolwich, and it protects 125 square kilometres of central London from flooding caused by tidal surges.
It became operational in 1982 and has 10 steel gates that can be raised into position across the River Thames. When raised, the main gates stand as high as a five-storey building and as wide as the opening of Tower Bridge. Each main gate weighs 3,300 tonnes.
Advantages:
It will give more security as water levels have been reported to have been 3 meters of the top.
Disadvantages:
£80 billion worth of damage could be caused is the infrastructure is not raised as water levels are rising the barrier will have to be raised with it.
The barrier is already feeling the effects of global warming where water levels have risen.
Stop building on the Thames Gateway
The Thames Gateway is an area of land which stretching 70 kilometres east from inner London on both sides of the River Thames and the Thames Estuary.
Advantages:
There will be less damage if the river floods
Other unused Brownfield land can be urbanised.
Cost less money to build and buy.
Disadvantages:
There may be a shortage of homes
Tourists would rather stay near the River Thames
Part of it is Brownfield land and the land will not be in use.
Design flood proof buildings
1.5 people live around the Thames and the majority of them don’t have flood proof buildings. This means if floods occur there buildings will suffer gravely due to lack of protection.
Advantages:
You can continue to build on the Thames Gateway as the buildings won’t be affected that much
If floods occur the damage won’t be large
Disadvantages:
Buildings may be less stable if not built properly
Building may not look as appealing to the eye.
The solution I would choose is design flood proof buildings as it would be the most benefited. There are already many buildings lining the Thames and to add a few characteristics would not cost a lot. Many building projects are taking place along the Thames Gateway, this is a high risk flood area and to add a few things that will benefit the people and the buildings wouldn’t be that difficult. The houses that are already there could be reinforced with different interior such as removable wooden panelling or water proof objects. Alongside items which can be taken to the top of the house at short notice. This will mean homeowners will not have to move house. There fore I believe you should choose this solution to overcome problems which may be faced in the near future.
