Why are tree roots a drainage issue?


Trees and plants bring numerous benefits to our homes and communities, such as providing shade, enhancing the aesthetic appeal of our surroundings and improving air quality.

However, it’s important for homeowners to be aware of the potential risks that tree roots can pose to drainage systems. When not properly managed mature plant roots can infiltrate and damage drainage pipes, causing blockages and costly repairs.

Thirsty plants need water

Intrusion occurs when roots seek out sources of moisture and nutrients, which can lead them to infiltrate drainage pipes. This is especially common in older drainage systems made of clay or concrete as the joints and cracks provide entry points for roots to grow into the pipes. Once inside the roots can expand and cause blockages, leading to slow or ineffective drainage, and even sewage backups in severe cases.

How to avoid drainage issues

To avoid problems, homeowners should take the following steps when planting and maintaining trees on their property:

  1. New tree placement

    Before planting any trees, consider their potential size once fully grown and their proximity to any drainage pipes. Certain species are more likely to cause problems than others, so it is important to choose trees with less aggressive root systems.

  2. Maintain a safe distance

    As a general guideline, the planting distance from any drains or sewer lines should be at least as far as the expected mature height of the tree. This will help to minimise the risk of root intrusion in the future.

  3. Regular inspection and maintenance

    Periodically inspect your drainage system to check for any signs of root intrusion, such as slow drainage or gurgling sounds. If you suspect root intrusion, it is important to seek professional help from drainage experts who can assess the situation and recommend appropriate measures.

If you suspect a problem in your drains due to tree root intrusion, it is crucial to address the issue promptly. Ignoring the situation can lead to significant damage and higher repair costs. By acting quickly, you can minimise the impact on your drainage system – and hopefully save the tree too – preventing further complications for yourself, your neighbours and future tenants.

Living with trees

According to the drainage specialists at BN Drainage: “Tree root intrusion is a common issue particularly as there are so many mature trees and plants in this area, with Kent often referred to as the garden of England. Many local homeowners are keen gardeners and take great pride in having a big, old tree in their garden or enjoy living in a spot overlooking one of the many parks and green spaces, so it is important for homeowners to be proactive in managing their own trees to prevent potential damage to drainage systems.

“Regular inspections and early detection can save a lot of hassle and expense in the long run. If you suspect root intrusion, it’s always best to consult with a professional to assess the situation and provide appropriate solutions.”

While trees and plants offer numerous benefits, their long powerful roots can pose a real threat to drainage systems if not managed properly. Homeowners must plant and maintain their trees responsibly, minimising the risk of root intrusion and ensuring the smooth running of their drainage systems for years to come.