World Water Day is an annual event celebrated on March 22. The day focuses attention on the importance of fresh water and advocates for the sustainable management of freshwater resources. World Water Day is also used to highlight required improvements for access to WASH (water, sanitation, hygiene) facilities in developing countries.
Every year, UN-Water proposes the annual theme and coordinates the global campaign alongside one or more members on behalf of UN-Water with the support of other members, programmes, partners and relevant stakeholders. The theme also sets the focus for the UN World Water Development Report, which is produced by UN-Water.
See more at http://worldwaterday.org/
The 2018 theme is Nature for Water.