Figure 1: Manitoba GHG emissions – 1990-2022 – Solid waste
Although waste accounted for only 6% of Manitoba’s greenhouse gas (GHG) emissions in 2022, it has increased significantly since 1990. The 2022 level was 53% higher than in 1990. (1)
The greenhouse gases (GHG) in the waste category are the on-site emissions from disposal of solid waste, as well as waste or wastewater treatment.
Sources of these emissions include the following:
- landfilling of solid waste
- flaring of landfill gas
- treatment of liquid waste
- waste incineration. (1)
A major source of the GHG from landfill comes from the decomposition of organic waste. (1) Organic waste in landfills produces methane. This is because the waste is covered in the landfill. This covering reduces trash blowing around and covers some of the smell. Once covered however, the organic material decomposes anaerobically (i.e. without oxygen) and produces methane. Methane has 25 times the Global Warming Potential (GWP) of carbon dioxide (CO2) on the 100-year timescale.
However, the Province of Manitoba and the City of Winnipeg put a capping system over the Brady Landfill in 2012. This system has been trapping the methane gases that would have escaped due to the decomposition of organic matter in the dump. The methane is being “flared” or burned off. Flaring changes the methane to CO2. This reduces the global warming by a factor of 25.
IF YOU COMPOST, the organic waste produces CO2 instead of methane. As plants grow, they take in CO2. If they decompose aerobically (with oxygen), they release about the same amount of CO2 as they took in as they grew. This could result in net zero emissions depending upon how the food was produced.
The Green Action Centre is a really good source of information about composting and runs Compost Winnipeg.
For a printable PDF file with the data, click here: Manitoba_GHG_trend_chart_1990-2022_waste.pdf – 89 KB
