Sewage treatment plants are the modern method of treating sewage where no mains connection is possible.
Domestic sewage treatment plants contain 1, 2 or 3 chambers, which separate solids from liquids, digest the pollutants and make the resulting effluent clean enough to be discharged into a stream, river or ditch with flowing water in it.
There are various designs, but they all achieve the same thing - clean effluent.
If you don't have a watercourse available, they can still use a drainage field, but the drainage field will be 20% smaller than that needed for a septic tank.
However, the same soil testing is required as for septic tank drainage fields.
Sewage treatment plants - Factors To Consider
- They digest the pollutants in the liquid part of the sewage and some also digest up to 98% of the solids as well.
- They can discharge directly to watercourses.
- The liquid waste is not polluting to the soil and will not kill any earthworms it touches.
- Requires emptying on a regular basis - depending on the make, every 6 to 12 months on average.
- Less expensive to install than a septic tank and drainage field.