With 414 mm (16 inches) of rain, England and Wales has not seen a wetter May to July since records began in 1766. The unusual weather was linked to the location and strength of the jet stream and unusually high Atlantic sea temperatures. The jet stream is a ribbon of strong winds which strongly influences the weather systems that bring rain to the UK. For much of this summer, the jet stream was further south and stronger than it is typical, resulting in more rain bearing depressions crossing southern and central parts of the UK. The warmer sea temperatures created more rain clouds.
Summer rainfall can often be very heavy but only last a short time. What was particularly unusual this year was the amount of heavy rain and the length of time it lasted. In May and early June the rain was partly absorbed by the dry ground. Once the ground became saturated by mid-June, the scene was set for future downpours to lead very quickly to localised and, if sustained, widespread river flooding. Many reservoirs that normally have some capacity to absorb run-off were also filled by the May and early June rain.
In mid-June Yorkshire suffered heavy rain in the north and west of the county. On 24-25 June the worst rain was in Yorkshire,
Humberside, Lincolnshire, Derbyshire and Worcestershire. Four times the
June average fell in places on the North York Moors and in the South
Pennines. At Emley Moor in the South Pennines the June rainfall was
294mm (11.5 inches).
From late on 19 July and throughout 20 July, extremely heavy rain moved northwards across the UK, with the heaviest rain falling in the south Midlands. At Pershore College in Worcestershire 157 mm (6 inches) of rain fell in just 48 hours compared with 252 mm (10inches) over the month as a whole. Four times the July average rainfall fell locally in the
South Midlands.
The result of the economic loss and social distress turned the summer of
2007 into a national catastrophe. Estimates of the financial side of the equation put the total damage caused by the flooding to 3.2 Billion £, from which 67 % (2.12 Billion £) of the total economical costs were incurred by
Households and businesses. The flooding caused damage of about 674
Billion £ to important national infrastructure and the operation of essential services. Damages to about 42 000 ha of farm land accounted for about 2% of total flood costs. The scale and seriousness of the summer
2007 floods were sufficient to classify them as a national disaster.
In addition to the impacts to school services. 467 schools were flooded or were affected in some way by the July floods, which resulted in a loss of 37.6 Billion £ . The total cost of the flooding According the UK Resilience Report (Cabinet Office, 2008) 170,000 pupils lost a total of 400,000 pupil days in the Yorkshire and Humberside floods alone.
However, it is recognized that the impacts on the lives and livelihoods of those caught up in the floods cannot be expressed in monetary values alone. For many people affected, the flood were a personal tragedy from which full recovery may be very slow or not possible.
The floods certainly tested whether emergency responders were ready and able to react effectively. In general the incident command system worked well. Skilled resources and equipment was shared across the regions. In total 1,200 flood risk management staff and
1,000 other staff from the Environment Agency gave a significant amount of their time to manage the incidents.
The Operations Delivery team worked tirelessly and succeeded in protecting key infrastructure, such as Walham electricity substation, without which 500,000 people would have been without power.
The agency was unable to install temporary flood defences in time because of severe flooding problems on the roads. This meant that the barriers could not be transported from the depot in
Kidderminster. We now know that even if the barriers would have been installed at Upton, they would have overtopped by the unprecedented water levels. At Worcester, approximately 10 properties on Hylton Road were flooded because the barriers were not installed.
It was clear that it should be planned early to recover from flooding. The flooding shut down many sewage treatment works and work has been done to minimise the impact and get treatment facilities back up and working as quickly as possible.

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