Water treatment is an energy-intensive process, and both solid and liquid wastes may emit greenhouse gases (GHGs) during decomposition. As such, techniques to reduce the demand for water treatment and reduce the amount of wastes entering landfills can help to reduce GHG emissions.
To reduce water demand, the most important target is the agriculture sector, which is often the largest water user (for example, in the U.S., agriculture is responisble for 80% of water use). The U.S. EPA reports that "as much as 50 percent of the water we use outdoors is lost due to wind, evaporation, and runoff caused by inefficient irrigation methods and systems." Thus, a key method of reducing water demand is to optimize irrigation timing and delivery systems. Outside of the agriculture sector, techniques for reducing water demand include the use of drought-tolerant native vegetation for outdoor yards and landscaping and use of efficient indoor fixtures.
Methods of waste reduction include avoiding excessive amounts of disposable packaging, greater product longevity, repair, and re-use, composting of biogenic waste, and recycling.