Results on methane emissions are presented in Table 4 and 5. It was discovered that methane emission from sewage treatment by using IPCC (2006) method had the highest values in 2009, followed by 2010, 2011, and 2012. The results indicate that the methane release declined over years. The variables that had a major influence on the outcome of the calculation were the BOD value and population.
Nitrous oxide emissions from wastewater effluent are presented in Table 6. Population was the major
factor affecting the emission of nitrous oxide from wastewater. Nitrous oxide emission increased when
population increased.