Urban creep, also known as urban sprawl, is the gradual expansion of urban areas into previously rural or natural areas. This can have a significant impact on drainage design and soakaway design calculations, as it can increase the amount of impervious surface (such as paved roads and buildings) and reduce the amount of permeable surface (such as soil and vegetation) available to absorb and store water.
When urban areas expand, they often replace natural landscapes with buildings, roads, and other hard surfaces, which can lead to an increase in surface runoff and a decrease in infiltration. This can put a strain on existing drainage systems, which may not have been designed to handle the increased volume of water. As a result, urban creep can lead to an increased risk of flooding and water pollution.
One way to mitigate the impact of urban creep on drainage systems is to incorporate green infrastructure (GI) into the design. GI is a network of natural and semi-natural features such as parks, gardens, streets, and green roofs that can provide a range of benefits including improving air and water quality, reducing flood risk, and providing habitats for wildlife. By incorporating GI into the design, urban areas can become more resilient to the impacts of climate change, such as heavy rainfall and sea level rise.
It’s important for urban planners and drainage design consultants to consider the potential impact of urban creep when planning new developments, and integrate strategies to reduce its impact on drainage systems.
For more information on urban creep and its impact on drainage design, you can visit the following websites:
- Natural England: https://www.gov.uk/guidance/green-infrastructure-gi-and-urban-sprawl