Synergy News & Blog: News
The Hidden Danger of Blocked Drains in Schools: Problems and Mitigation Measures
Ensuring a Safe and Healthy Environment for Students
Synergy has been involved in numerous projects to remedy drainage failures.
Leaks, blockages, or collapses of the drainage system can result in significant issues affecting the school premises.
These issues have led to health and safety concerns, costly repairs, and extensive long-term disruption to educational activities.
This article explores these potential issues and discusses effective mitigation measures that schools should implement to protect their drainage system.
Figure 1: Unusable playground due to flooding resulting from a blocked foul drain
Understanding the Causes of Drainage Failures
Accumulation of Debris:
Blocked drains can result from a variety of factors, including the accumulation of debris, food waste, sanitary products, and even small objects that find their way into the drainage network.
Over time, these materials build up and create blockages that can impede the flow of water and waste.
Ageing Drainage Systems:
Ageing drainage systems present other risk factors. For instance, pitched fibre pipework, which was first utilised in the 1950s and 1960s, is still commonly found.
As pitch fibre pipes age, they are subjected to pressure from ground movement, leading to potential collapse, deformation, or blistering.
Such issues result in blockages. When blockages occur, they are typically addressed using drain rods, or in severe cases, high-pressure water jetting. Unfortunately, both methods can further damage the aging pitch fibre pipes’ inner surface, causing delamination and consequently weakening the pipes even more.
Figure 2: Partially collapsed delaminated pitch fibre pipe
Tree Roots:
Tree roots can also cause significant problems to drains. Tree roots naturally seek out moisture and nutrients and drains provide an ideal environment for their growth. Roots are attracted to moisture from leaks or condensation in pipes and the disturbed soil around trenches also makes it easier for them to reach the pipes. Once inside drains, roots can expand and cause blockages, pipe damage, or even break pipes completely.
Climate Change:
One of the most immediate consequences of the climate emergency is the transformation of regional and global weather patterns.
Most historical drainage systems were designed based on rainfall records and population densities from decades past. With climate change, peak flows are often much greater than those original design parameters, causing systems to become overloaded.
Meanwhile, prolonged droughts can lead to soil compaction and subsidence, affecting the stability and integrity of buried drainage pipes.
Intense storms often wash debris, silt, and litter into stormwater inlets. Climate change increases the likelihood of these events, compounding the risk of blockages
Some of the Problems Caused
Blocked drains in schools can lead to several significant problems:
Health and Hygiene Risks:
When drains are blocked, toilets and other foul wastes can back up, creating unsanitary conditions.
Exposure to pathogens resulting from raw sewage can cause respiratory issues, infections, and other health problems. This can pose serious health risks for students and staff.
Property Damage:
Blocked drains can cause water to overflow, leading to flooding and water damage. This can affect floors, walls, and ceilings, resulting in costly repairs and potential structural issues. In severe cases, where drains have leaked for a long time, water damage can also compromise the integrity of the building or surrounding ground making it unsafe for occupancy.
Figure 4: A flooded school kitchen. This flood caused significant disruption to the school and was costly to clean and repair.
Disruption to the Learning Environment:
Blocked drains can disrupt the daily operations of a school. Classrooms, playgrounds and facilities may need to be closed for cleaning and repairs, causing interruptions to the learning schedule.
This can significantly impact students’ education and create logistical challenges for staff and parents.
“We get many issues with the toilets backing up and flooding. Most days in the winter and during wet periods, the toilets need unblocking, or the raw sewage comes back into the toilet pan and the toilets are unusable.
I am often coning off areas outside that are flooded and many times the play areas are unusable for several days at a time. The water that is lying on the ground is very dirty and I am worried that this is dangerous when the children play near it”
Recent comment from a Premises Manager from an affected flooded school in London.
Mitigation Measures for Schools
To prevent and address the problems associated with blocked drains, schools should implement the following mitigation measures:
Regular Maintenance and Inspections:
Similar to regular fixed wiring electrical and legionella testing; drainage surveys should be regularly undertaken to understand the condition and to clear minor blockages before they become a bigger problem.
This is recommended in the DfE’s guidelines ‘Good Estate Management for Schools’ (GEMS).
Synergy recommend that this is carried out at least every five years, but it’s of course important to investigate any problems as they occur.
This routine maintenance and inspection of the drainage system can be carried out at a relatively low cost and will help identify and address potential blockages before they become severe.
Figure 5: Regular inspection and maintenance of drainage systems is essential.
Educating Students and Staff:
Creating awareness among students and staff about what should and should not be disposed of in drains can help prevent blockages. Schools can provide educational materials and training sessions to emphasise the importance of proper waste disposal.
Installing Protective Measures:
Schools can install drain covers and strainers to prevent large debris and objects from entering the drainage system. These protective measures can help reduce the likelihood of blockages and make it easier to maintain the drains.
Emergency Response Plan:
Having an emergency response plan in place can help schools quickly address blocked drains and minimise disruption. This plan should include clear protocols for reporting and handling blockages.
Upgrading Drainage Systems:
For schools with outdated drainage, upgrading the system can be a long-term solution to prevent blockages.
Modern systems are designed to handle higher volumes of water and are less prone to blockages. In their estate planning, schools should prioritise infrastructure improvements to ensure the safety and functionality of their facilities.
If the school is an academy, Condition Improvement Funding (CIF) or School Condition Allocation (SCA) are avenues to fund these works.
Nature-Based Solutions:
Green infrastructure – such as swales, SUDS planters, rain gardens, and permeable pavements—help to slow and absorb runoff, reducing pressure on underground systems.
Conclusion
Blocked drains in schools are a hidden danger that can have far-reaching consequences.
By taking proactive measures such as regular inspection and maintenance, proactive cleaning and root removal, educating staff and pupils, installing protective measures, creating emergency response plans, and implementing drainage system upgrades schools can ensure their estate is protected and ensure a safe and healthy environment for students and staff.
