What is Fluvial Flooding?
Fluvial flooding, also known as river flooding, refers to the overflow of water from a river, stream, ditch, or watercourse that causes water to inundate the surrounding land. This type of flooding occurs when the water level in a river exceeds the level of the bank, causing the water to flow onto adjacent floodplains. Fluvial flooding can be caused by heavy rain, river channel blockages, high tides, and other factors, and it can result in damage to homes, businesses, and infrastructure. The risk of fluvial flooding is expected to increase with more intense rainfall due to climate change. However, the flood risk associated with watercourses are not the only sources of flood risk in the UK. Floods can also occur due to surface water, reservoir overflows, groundwater or infrastructure failure. Fluvial flooding can cause significant damage to homes, businesses, infrastructure, and natural habitats, and can pose a serious risk to human life.
What is considered a Fluvial Flood?
A fluvial flood is generally defined as a significant overflow of water that overflows onto usually dry land. However, it is important to note that different kinds of floods come with different impacts and require different protection and preventative measures. The severity of floods is mainly determined by the intensity and duration of rainfall in the river’s catchment area. However, multiple other factors can increase flood risk such as soil water saturation, how flat the terrain surrounding the river is and the drainage of the surrounding area.
What Other Forms of Flooding Are There?
The two other main flood types are Pluvial Flooding and Tidal Flooding.
Pluvial flooding is a type of flooding that occurs when there is an excessive amount of rainfall that cannot be absorbed by the ground, leading to the flooding of the surrounding area. Unlike fluvial flooding, which is caused by overflowing rivers, pluvial flooding is caused by intense rainfall overwhelming the drainage systems in urban areas or watercourses that are usually dry. Pluvial flooding can occur in any location, but it is more common in densely populated areas with high levels of impermeable surfaces such as pavement, roads, and buildings, which can prevent the water from soaking into the ground. With the increasing frequency and intensity of extreme weather events, the risk of pluvial flooding is expected to increase, especially in urban areas.
Tidal flooding, also known as coastal or storm surge flooding, occurs when sea levels rise and water inundates low-lying coastal areas. This type of flooding can be caused by high tides, strong winds, storm surges, and other factors that cause water to accumulate along the coast. Tidal flooding can cause significant damage to homes, businesses, infrastructure, and natural habitats. With rising sea levels due to climate change, the risk of tidal flooding is expected to increase in many coastal areas around the world. Local authorities and environmental agencies often implement measures to protect against tidal flooding, such as sea walls, flood barriers, and other forms of coastal protection.
Do I need a Flood Risk Assessment?
Our Flood Risk Assessments will assess all sources of flood risk associated with your development, including fluvial flooding. We will incorporate any necessary flood mitigation measures which might be needed to reduce the risk of all forms of flooding, ensuring your development remains compliant with both national and local policies, ensuring a smooth planning approval process.
We work alongside developers, architects and homeowners to ensure that any associated sustainable drainage systems, which can mitigate the impact of climate change, are as environmentally and ecologically sustainable - thus, increasing the likelihood of a successful planning submission.