WatSan Action (formerly known as Yayasan Emmanuel Water Program), officially became a U.S. tax-exempt 501(c)3 organization in 2004, though the concept for creating it started in 2002. Mindy Weimer teamed up with a fellow Jakarta International School alumni, Emmanuel Laumonier to open the Water Program as part of his organization Yayasan Emmanuel (YE).

Initial project focus was on both urban and island communities in Indonesia in need of technical aid to address environmental issues, and to concurrently foster constructive service-learning projects. Rainwater collection and program structuring were the main focuses in 2004. YE Water Program managed to establish groundwork for project developments with the help of four resourceful volunteers.

The need for improved hygiene (i.e. water handling, safe storage, etc.) was evident through the initial assessments, and became a precursor to implementing drinking water treatment projects. Furthermore, concentrating on replicable projects for underserved communities in Jakarta proved a more manageable scope than to include island communities. Hence, priority was allocated to establishing a Public Health Promotion program focused on underserved communities in Jakarta.