Setting Up soak away drains, do this 1st
Before starting any plumbing, soak away or sewage work yourself you should find out about any Local Authority rules that relate to your area.
If you are changing your current soak away drainage, building a soakaway or installing a new system, you will most definitely be asked to show detailed designs of the implementation that you have in mind and it will need to be overseen as the work moves forward to ensure that it is compliant with local building rules. However you do not require authority approval for replacement of failed joints or cracked plumbing and drains pipes.
Whatever water we see on the surface around your home is usually rain. It can drain out through a soakaway, watercourse, surface water sewer or, especially in older houses, into the dirty water drainage pipes. If gully traps are fixed at the junction of the rainwater pipe and the waste water drain, foul odour can be controlled. However, the latest systems are designed in a way which separates the foul water and the surface water. It is extremely important to ensure that you do not connect foul water to a surface water soakaway or drainage system. When in doubt about the how the modern drainage system works, consult the Building Control Department.
To properly prepare the plans and get local authority permission to commence work there is a need for you to plan the route of the waste pipes before you begin. Have an eye to future care when you design the sewage system and always try to keep the waste or soil pipe as straight and short as you can when you are devising the layout. You must avoid making your soakaway pipe runs too steep. You can calculate the fall of a drain over a distance using a surveyors site level. In case you don’t have a surveyors site level, choose a datum point and then a water filled hosepipe can be used to calculate the fall from there.
When installing your drain ditch, you will need to make sure that you do not impair the stability of the building. You have to make sure that no building foundation is weakened if you are laying a drain running parallel to the building.
When fitting in a new sewage or building a soakaway system, you should not dig the trench too long before placing the pipe as the ditch could collapse. Get the pipes laid quickly and, as soon as they have been tested, fill the ditch back in.
Be wary of the depth and soil conditions and if necessary add extra support to the ditch. Avoid risks when working in the trench. If in doubt add support to the trench to prevent it from collapsing. Keep the ditch as narrow as you can but of course make sure that there is enough room to work in the trench including any plan, machinery or tools you require. The base of the ditch should be clean and even and free from protruding stones or bricks etc. If the existing soil is too weak or clayey, you should place and compact a layer of firmer soil at the base of the ditch to prevent later sinking.
For pipe support do not use bricks or other hard materials in the ditch. This will damage the pipe and must never be used as temporary or permanent support. For accommodation of the joints in the pipes,the bedding should be compacted in a regular way with hollows made a appropriate points. For the complete pipe length you have to provide a continuous and uniform support.
An important criteria for pipe layout is that you should be able to access any point with a drain rod to clear blockages. The drains to a soak away or sewer should therefore run straight between two points to ease the passage of the drain rods. Always make sure that rodding access is allowed in an inspection chamber at any point where the direction of the pipework changes.
If you are keen on DIY and follow some basic rules then you will be able to do plumbing, soakaway and sewage work on your own.