Drainage in all buildings is necessary to remove waste, foul and surface water. Waste and foul water join together and are disposed of in a septic tank or to the foul water sewer. Surface water, however, can be discharged into a soakaway. The soakaway then discharges water slowly into the sourrounding ground area.
Foul drainage, below ground, removes the waste from the toilet, bath, basins, sinks, washing machines, dishwashers and showers. Surface water drainage, above ground, deals with rainfall as it collects around your property. In older houses the surface water is often fed into the foul water system. Foul water is never allowed to be fed into a surface water system. All underground water pipes are brown in colour to distinguish them from any other underground service pipes.
ABOVE GROUND DRAINAGE
Rain water lands on your roof and runs down into your gutters. From your gutters, it is directed to the surface water drainage downpipes and then into a soakaway. The surface water drainage system operates in much the same way as the foul drainage, with manholes at junctions and changes of direction.
Water will always find the lowest point to drain to, so the outlet pipe of a gutter must be the lowest point. The Gutters should be cleaned regularly, especially if you have trees near you. Clogged gutters can lead to wet walls, which in turn can lead to damp and mould.
A leaf grid in the top of the gutter downpipe will help keep leaves in the gutter where they are easier to clean out, rather than let them block the downpipes or gulleys. The surface water not collected by the gutters should drain away harmlessly into the sourrounding ground.
BELOW GROUND DRAINAGE
When the toilet is flushed or water released from sinks, basins and the like, water and waste is forced round the bends into the pipe which carries it through the wall of the property and out into the mains drainage system or, in some cases, a septic tank. This pipe is called a soil and vent pipe, the vent part of the name indicating that the pipe carries the foul gasses up to and beyond the roof line.
Once the waste has left the property, it is directed to an inspection chamber where more pipes may join. These pipes can come from other outlets in your home, or from other houses in your area. Inspection chambers are placed wherever two or more pipes join, or a single pipe changes direction. An access chamber or manhole will allow access to any blockages if they occur.
The majority of houses in the Channel Islands are linked up to the public sewage system. You pull the plug, flush the toilet, pay the monthly bill and have little to worry about. This is Mains Drainage.
In country areas some homes are self-contained wih the waste ending up in a Cesspool, Septic Tank or Treatment Plant. This has no connection to the public sewer system and is known as Off-Mains.
A Cesspool is simply a single-chamber storage tank with no outlet. The tank is usually very large as it has to contain all waste water and sewage, and often made from concrete or brick. The only way to dispose of the waste is by calling a sewage contractor to remove the sewage for off site disposal. The use of Cesspools is no longer an option in most instances.
A Septic Tank is a multi-chamber storage tank allowing liquid and solid waste to separate. The liquid is allowed to flow out of the tank and be disposed of separately. The sewage enters a settlement chamber, allowing solid waste to sink and the liquid to rise to the surface. This liquid still contains sewage but in small enough particles to be carried through the discharge outlet and into the ground. Septic Tanks only partially treat sewage.
A Treatment Plant is a packaged miniature sewage-works that converts raw sewage into water effluent and solid waste. These plants come in all shapes and sizes but all use the same science in their process of tackling sewage.
No Treatment Plant is a ‘fit and forget’ product as they do require periodic maintenance and a degree of care to keep working to optimum levels. What they do offer though is the most environmentally and authority friendly way of solving an off-mains drainage problem.
Separators and silt traps remove pollutants from effluent and allow the cleaner water to be passed into a surface water drainage system. Pollutants are retained for removal and disposal.
Separators work by allowing the pollutants and water to naturally separate out from one another, pollutants will float on the surface of water and can then be drawn off. Silt will also settle within the unit and can also be drawn off.
All our above and below ground drainage is available to collect from our drive-through, shop and back yard in Rue des Pres Trading Estate, St Saviour, or delivered free of charge to any destination islandwide. Pop in, contact us or call us on 01534 888000 for more information.