It is estimated that 2.5 billion people around the planet have no sanitation facilities. To address the problem, EU has funded a study that measures?the effectiveness of earthworms, water fleas and microalgae as a carbon neutral method of treating wastewater.?The aim of the project is to help improve access to clean water across the world. Scientists are particularly keen to learn whether the bugs can survive in colder northern climates. The system is being trialed in 10 other countries but Scotland is the most northerly, and it was chosen for this project because of its cold climate.
Two tanks have been installed at an existing treatment works to pilot the technique which aims to reduce the environmental impact from sewage. The first stage of treatment involves a tank filled with earthworms. The worms eat the larger particles of organic matter in the waste water, before it is added to a second tank containing water fleas and microalgae which remove the finer bits of organic matter. According to the leader of the project Anna Baran, this technology replicates a process which happens naturally within soil but the scientists are using it to clean waste water.
During the 12-month trial, the water will still be treated using conventional methods once it has passed through the new machinery. If the technique proves successful, it could be used in developing countries where access to clean water is limited.
The project has the potential to make a significant impact on the way waste water is dealt with around the world.