Septic Soakaway Advice, Tank Drainage Design and Installation

Septic Tank Soakaways and Drainage Fields - How they work 

• It uses naturally occuring aerobic soil bacteria to further clean the pollutants in the effluent
• It disperses septic effluent into the soil

The Environment Agency has confirmed to us that DEEP BOREHOLE soakaway drilling as a method of solving drainfield issues is NOT generally acceptable to them.  BEWARE of such adverts on the Internet!

The size of the soakaway or drainage field will be dependant on the following factors,

1. The porosity of the soil.

2. The size of the property (based on the number of bedrooms) and the number of residents it serves.

However, older septic tank drainfields sometimes did not have to conform to any Building Regulations and may be a simple long trench, a herringbone drainage layout or a large stone filled pit.  All these latter types are often not fit for the purpose as percolation tests were not carried out and they are frequently inadequate.

All soakaways have a limited lifespan which is made shorter if the correct emptying and maintenance of the septic tank is ignored.  If you do not empty your tank on a regular basis the suspended solids from the tank will be forced down the drains and into the soakaway, clogging the pipes and contaminating the soil with a black, slimy biomatt, making the drainfield no longer effective.

Rules and Regulations for Septic and Foul Drainage soakaways

• Buildings - 15 metres
• Boundaries - 2 metres
• Water abstraction point (well, spring, borehole) - 50 metres
• Watercourse (ditch, stream, river) - 10 metres
• No access roads, driveways, paths, buildings, etc. should be within the drainfield area.  If it is in a field, then tractors are not allowed to drive over it.
• No water or electric cable or pipes should be within the drainfield area.
• The bedrock or water table should not, at any time, be within 1.2 metres of the drainfield pipework.

If you have a question about your septic tank soakaway give us a call on 01757 288022 and we can normally arrange a free survey and diagnosis of the extent of the septic tank soakaway system problem.