School Drainage Systems

Sites such as schools and colleges often have complex drainage systems that have been constructed over several decades using whatever was the favoured material at that time, as the site evolves many original external systems are built over leading to inspection chambers being located in courtyards, corridors and even class rooms.

So school drainage systems bring their own unique challenges with regard to repair and maintenance including how and when to work on them in a safe manner without causing major upheaval or disturbance, we can however give a general overview of the typical problems we come across on school drainage systems.

School Drainage Maintenance

Playgrounds, car-parks and large roof areas have to deal with large volumes of rain water often in a short space of time, therefore if gullies, road gullies and linear channel drains are not maintained and cleaned the water run off can not make it into the below ground drainage system and you get localised flooding.

A natural build up of silt and debris over many years will cause blockages in grids and gullies situated in playgrounds however crisp packets, aluminum cans, plastic bottles and tennis balls are also common place, the silt from large hard standings can also build up within the below ground drainage system over many years leading to a restricted flow.

Maintenance Cleaning of School Drainage

After many years of neglect a full site clean is required with all gullies, grids and linear channels being emptied and the main line below ground drainage being flushed through, once this initial clean has been done an annual visit to empty and flush test all gullies and grids is a cost affective way of keeping on top of things.

As part of the above works we are often asked to map out the system and mark up a site plan, depending on how detailed a report is required this can easily be extended to a full charting and mapping exercise using drain camera inspection equipment.

School Drainage Construction

It really depends when the site was constructed and many schools and colleges will have buildings that span several decades;

Victorian sites through to the 1960`s will usually have vitrified clay drainage externally and cast iron drainage beneath the building itself, the clay drains are prone to root ingress, fractures and displacement of joints and the cast iron pipes of this era start to corrode on the internal wall surface leading to snagging of paper and waste.

From the late 1960`s to mid 1970`s pitch fibre pipe work was used, a terrible product with a known working life span of 40 years, cast iron and clay drainage was also still in use. From the mid 1970`s onwards modern clayware systems, plastic pipe work and treated or lined cast or ductile iron systems have been used.

School Drainage Charting & Mapping

This is often required by engineers if they are planning new build or extension so they know what they have to connect into drainage wise and what is running beneath or local to the footprint of the proposed new build.

Storm Water Rates (Rain Tax)

If you are being charged by your water company to treat all the storm water that falls on your site and you suspect that all or part of the rain water runs to a river, brook, water course or even a soak-away a full site survey is required before you can apply for a reduction in your water rates.