Treating sewage

Rapid rise in the number of visitors at the National Audubon Society's Corkscrew Swamp Sanctuary, southwest of Florida, USA, has resulted in an alarming increase in the amount of waste generated. But the sanctuary, in consonance with laws of Florida, has built a comprehensive sewage system to treat the wastes. The sanctuary got Living Technologies, a company based in Vermont, to develop a cost-effective and completely organic system of sewage treatment. The treatment facility, called Living Machine, can recycle up to 45,460 litres of wastewater per day. About 90 per cent of this is recycled back to toilets. The remaining 10 per cent is discharged into an absorption pond (Environment , Vol 39, No 6).