What we do
Flood Risk Assessment
Climate change and high levels of development have combined to increase the risks of flooding, and the damage it causes. The UK has seen serious flooding in 1998, 2000, 2002, 2004, 2005, 2007, 2009, and again in 2012.
The floods of Easter 1998 alone caused five deaths, £400 million of damage and resulted in 1,500 people being evacuated from their homes. The floods two years later damaged around 10,000 properties in the UK. The 2005 floods caused £250 million of damage and in 2007 six people were killed. In 2012, one UK insurer alone estimated its insured losses at £50 million by June, with more claims (estimated at £10 million a month) coming in all the time.
It’s not just the climate, although mild wet summers and near-tropical downpours throughout the year are becoming a fact of life. Urban development has led to more and more of the UK becoming covered in concrete. Rainfall that would once have soaked into the ground is now more likely to run off and cause floods.
Approximately 10,000km2 (or eight per cent of the total area) of land in England is at risk from river flooding, including tidal rivers and estuaries. Almost one-third of the coastline is developed and some 2,500 km2 of land (1.5 per cent of the total area) is at risk of direct flooding by the sea. As a result, about 1.7 million homes and 130,000 commercial properties worth a total of more than £200 billion and 1.3M Ha of agricultural land worth about £7 billion are at risk from flooding. This equates to about ten per cent of the population and 12 per cent of the agricultural land, including 61 per cent of Grade 1 agricultural land.
Incidences of river flooding are growing worse in both frequency and scale. This is caused by changes in river hydrology due to human activity, changes in land management, variations in the intensity of rainfall and increased development in areas at risk. Climate change is expected to increase the risk of coastal and river flooding as a result of sea-level rise and more intense rainfall. On both a national and global scale, damage from flooding is greater than that from any other natural disaster.
Local authorities are instructed by the department of the Environment to bear these considerations in mind when framing their planning policies and in determining applications for planning permission.
These threats to the environment, high economic costs, and the peril to human life mean that flood risk assessments are now an accepted process for anyone who is planning to build or develop. The Environment Agency’s guideline PPG 25 says that any construction activity likely to affect a flood plain must contain elements within it that mitigate potential flood problems. In effect, this means that all developments must have a flood risk assessment because, crucially, the guidelines say that developments outside flood plains are equally bound by this ruling. It is the likely effect of the development on the environment that must be considered – not whether the development is likely to be flooded itself.
This means that anyone planning a significant construction project must have expert impartial advice about the best way of managing and containing potential flood risk. This is a specialist area of professional expertise, outside the competence of architects and builders, that requires professional experience, knowledge, and the application of state-of-the-art modelling tools.
Rolton Group have specialist experience of flood risk assessment with a wide range of clients. After we have made a flood risk assessment, the output of our expertise is a report that quantifiably assesses the likely risk of your proposed project being affected by flooding.
We will give you a recommendation for incorporating the likely risk into your building plan.
All construction projects require a flood risk assessment. It makes sense to have your assessment carried out by specialists who can give you an accurate assessment of your risk and a sound and effective plan to mitigate it. To find out more about flood risk assessments, contact Rolton Group on 01933 410 909.