3.17 3.13 3.21 3.52 3.27 2015 BASELINE 2016 2017 2018 2019 2020 96 https://www.wri.org/aqueduct https://www.alcoa.com/global/en/who-we-are/ethics-compliance/water-stewardship-policy Category 1 water is of a high quality and suitable for most purposes with little or no treatment.