A sustainable infrastructure strategy addresses the greenhouse gas emissions that are released at all points of infrastructure systems, including:

• Pumping water, wastewater or stormwater.
• Treating water or wastewater.
• Hauling solid waste. 
• Landfill emissions from decomposing waste.
• Burning fossil fuels to produce heating, cooling, or electricity, where this is part of the local infrastructure.
• The facilities, equipment and materials involved in all infrastructure systems.

However based on current data sources (which are somewhat limited) the three largest sources of infrastructure-related greenhouse gas emissions typically are:

• Landfills due to methane emissions.
• Water distribution due to energy consumption.
• Wastewater treatment due to energy consumption.