“Due to their interdependent nature, these three core issues are grouped together to represent a growing sector. While each a separate field of work, each is dependent on the presence of the other. For example, without toilets, water sources become contaminated; without clean water, basic hygiene practices are not possible.”
Source: United Nations Children's Fund. 2016. "About WASH". UNICEF. <https://www.unicef.org/wash/3942_3952.html>. Accessed 8 April 2020.