The Chlorine Dispenser System
Developed in 2007 through collaboration between Innovations for Poverty Action and researchers at Harvard University and the University of California, Berkeley, this innovative technology provides a simple, affordable water treatment solution for use in poor areas where people lack access to safe water from a piped system. The CDS consists of three components:
- The dispenser casing, tank, and valve are made from injection- or blow-molded high-density polyethylene (HDPE), a plastic suited to long-term storage of sodium hypochlorite.
- The dispenser is covered with instructional stickers explaining proper use, and the casing locks to ensure the security of the tank’s contents. The casing is bolted to a 4” concrete-filled polyvinyl chloride (PVC) pipe and cemented into the ground near communal water sources, where it acts as a reminder to treat water at the point of collection.
- The valve is calibrated to release a 3mL dose of 1.25% sodium hypochlorite solution, enough to treat 20L of clear water for up to 72 hours (depending on the storage vessel).
- To use the dispenser, community members turn the valve to dose their jerricans and then fill the containers with water as they normally would. The chlorine mixes with the water as the container is filled and transported home. After 30 minutes, the water is ready for drinking.
- Chlorine protects against recontamination during transport and storage, helping deliver safe water at the point of consumption.
- Treating water with a dispenser is quick and easy. The dispenser ensures that chlorine is readily available at the water source, while the 3mL valve increases dosing accuracy.
- The public nature of the dispenser helps to encourage adoption. Given strong social ties in rural communities, seeing other community members using the dispenser can lead to powerful norm formation around water treatment and encourages peer education about safe water practices.
- DSW estimates that chlorine dispensers can be provided for under $0.50 per person per year at scale by using inexpensive bulk chlorine refills and simple long-lasting hardware. The low cost and large health impact make this program highly cost-effective by international standards.
Dispensers for Safe Water is an IPA initiative dedicated to implementing and scaling the Chlorine Dispenser System, an innovative water treatment technology. Our mission is to provide safe water to vulnerable populations. To achieve this goal, we work with public, private and non-profit sector partners and local communities to implement evidence-based, cost