Methane emission from open drain

Abstract

Solid waste that comes along with the wastewater from household gets deposited at the bottom of the drain. With passage of time, this solid waste starts decomposing and starts releasing methane. Methane is an important greenhouse gas, which is non-toxic but highly flammable. It is also an asphyxiant and can be fatal. Every year several people die for this reason while cleaning solid sewage of choked drains. Methane emission measurements from three drains of Kolkata were made during 2009-2010. The results are presented in this communication. It is found that methane emission from drains is ~4-100 times greater than that from paddy field. Data obtained in this work will be a valuable input for making reliable prediction of methane loading in the atmosphere and alert workers of the danger in order to take adequate safety measure before cleaning sewage sediments.