Fig. 3. Wastewater reuse and water-saving schemes discussed in the text, arrayed relative to a few key attributes (A) and performance indicators (B).The color scheme matches that in Fig. 1; substituting, red; regenerating, blue; and reducing, green. Certain schemes can be classified in more than one way;for example, wastewater recycling with wastewater stabilization ponds might be considered blue or red, depending on the end use and what water is being substituted or regenerated. The adoption of water-saving schemes is influenced by policy, law, regulations, markets, and incentives.