Floods and Fencing

Of the 28 million homes in the UK, over 5 million are prone to flooding – or one in six in England alone. But around 40% of these householders are blissfully ignorant of the fact that their homes are at risk!

Flood Prevention Tips

To make sure you don’t end up joining the growing queue for insurance claims relating to flood damage, here are some steps to take to prevent or limit the amount of water, which is able to enter your property following extreme weather conditions.

• Sandbags are a popular short term fix, which, when used with plastic sheeting, can help to prevent mud and silt from entering the property. However, they are not proven to prevent all water from weeping through.
• If you are aware that a flood situation is likely to occur, it is possible to install guards that will prevent water gaining access to your home via gaps in the front / back / patio doors.
• Ventilation bricks which could potentially provide a pathway for water can be screened off by fitting covers.
• If you are living in a flood prone area, it may be wise to ensure all floors are properly sealed.
• Tactical landscaping so that the garden slopes away from the house can help reduce the amount of water that is able to access the property – be aware that hard landscaping can increase the levels of water ‘runoff’.
• Consider fitting non-return valves in sewage pipes to stop sewage backing up into the house.
• Look at installing a perimeter fence which has built in flood defence qualities.

For further information on flooding visit www.floodforum.org.uk. You can also view areas at risk of flooding on the Environment Agency website www.environment-agency.gov.uk.

Installing Fences in Flood-Prone Areas 

When installing a fence in an area prone to flooding, selecting the appropriate materials is crucial. Look for high-quality, pressure-treated timber, as it can better withstand prolonged exposure to moisture.

While it may be tempting to add wire mesh or netting at the base of your fence to prevent animals from escaping, this should be avoided in flood-prone areas. These materials can trap debris, leading to structural strain and potential fence failure. 

It’s essential to maintain a clear gap between the bottom of your fence and the ground, allowing floodwaters to pass through without obstruction. After any flooding event, inspect the fence and remove any accumulated debris to prevent long-term damage. 

Fence Installation in Flood-Prone Areas

Considerations for fences in flood-prone areas, proper installation is just as important as material selection. 

Fence posts should be buried and installed as deep as possible to ensure stability. The deeper the post, the more secure it will be against water movement. Using a generous amount of concrete or post-fixing mix will reinforce the foundation, preventing posts from shifting or becoming unstable during floods.

If your property is near a river, stream, or another water source, it could be a contributing factor to recurring flooding. 

Position your fence as far from the water source as possible to reduce exposure to floodwaters. If higher ground is available, install the fence there to increase durability and protection. 

Designs of Fence

Flooding is an inevitable occurrence in certain areas, particularly on floodplains. While it cannot be prevented, a well-designed fence can help mitigate damage. A fence should be designed to let floodwaters pass through rather than resist them. 

This reduces the force exerted on the structure, minimising damage. Where possible, align the fence parallel to the flow of water. This reduces resistance and prevents excess pressure from building up against fence posts, helping maintain structural integrity. By following these guidelines, you can ensure that your fence remains stable and durable, even in challenging flood-prone environments.

Directing Flood Water with Fences

In some instances, standard wooden fences can be used to potentially mitigate flooding, though this is not a recommended solution in most cases. While it may offer limited temporary relief, it is always advisable to invest in dedicated flood barriers, especially when the risk of flooding is high. In the UK, many areas are prone to sudden, intense rainfall, and there are dormant rivers and streams that only become active following heavy downpours.

If you are aware of the natural path or route of a dormant stream in your area, installing a properly constructed fence can help divert the flow of water and reduce the amount that reaches your property. However, it’s important to note that this is not a fool proof solution and should be considered only as part of a broader flood management strategy.

To maximise the effectiveness of fencing in directing floodwater, deep, strong fence posts should be used, and these posts must be securely concreted into the ground. Additionally, incorporating concrete curbs beneath gravel boards can help create a more resilient barrier that can withstand the force of water. Fencing materials, such as acoustic fencing with no gaps between the panels, may also be beneficial in preventing water from flowing through.

While these measures may help direct the water away from your property, they will not stop water from accumulating on the opposite side of the fence. Floodwater may still pool in certain areas, and over time, the fence may need to be inspected for any damage or wear caused by the water. Ultimately, for high-risk areas, it is crucial to consult with flood protection experts and invest in proper flood defence infrastructure to ensure the best possible protection for your property.

Example of a wooden acoustic fence installed to direct a flooded stream