Integrated Waste Water Treatment
▪ In the town of Arcata situated on northern coast of California, an integrated waste water treatment process was developed with the help of biologists from Humboldt State University
▪ The cleaning occurs in two stages:
i. The conventional sedimentation, filtration and chlorine treatments are given. The treated water still contains lots of heavy metals and other dangerous pollutants.
ii. Appropriate plants, algae, fungi and bacteria were grown in a marshland through which water was flowed. The various life forms neutralise, absorb and assimilate the pollutants and purify the water naturally.
▪ ‘Ecosan’ toilets have been developed in areas of Kerala and Sri Lanka for ecological sanitation.
▪ Advantages of ecological sanitation:
i. It is a practical, hygienic and efficient method of waste disposal.
ii. It is cost effective.
iii. Human excreta can be recycled into natural fertiliser to replace chemical fertiliser.