A septic tank is an underwater sedimentation tank used for waste water treatment through the process of biological decomposition and drainage.
A septic tank makes use of natural processes & proven technology to treat wastewater from household plumbing produced by bathrooms, kitchen drains,and laundry.
A septic tank system has a relatively simple design. It is an underground watertight container (mostly rectangular or round) made of fibre glass, plastic or concrete.
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A soakaway is a buried drainage feature which seeks to manage surface water on the site and infiltrate into the ground, rather than discharging to an offsite location such as a watercourse or sewer.
What are the advantages of a soakaway?
Takes water away from sewers and reduces the risk of flooding;
Infiltration into the ground is a natural process, which recharges the underlying aquifers;
If the land is available than a soakaway is a cost-effective option;
Low maintenance;
Can be fitted retrospectively.
What are the disadvantages of a soakaway?
Can interfere with building foundations;
Not suitable for poorly drained soils;
Field investigations including long-term groundwater monitoring required to test infiltration conditions and rates;
Not appropriate for draining contaminated runoff;
Increased risk of groundwater pollution.