Two million children die of diarrheal disease each year and contaminated water is often to blame.

Treating water with chlorine could substantially reduce this toll. The most common approach to chlorination in areas without piped water infrastructure is to offer small bottles of chlorine for sale to consumers.

However, chlorine use has been slow to catch on in this system, despite low costs and years of vigorous social marketing that has raised awareness about the product.

Based on this finding, a team of researchers affiliated with IPA has developed a way to drastically cut the cost of chlorinating water by reducing packaging and distribution costs -- which account for the majority of the price of chlorine sold in individually-packaged bottles -- by installing chlorine dispensers at communal water sources. Users turn a knob on the dispenser to release a pre-measured dose of chlorine appropriate to treat the volume of water typically collected. The presence of a dispenser provides a reminder to treat water and harnesses peer effects to help increase take-up.

Through a randomised evaluation, this project found huge increases in chlorine use (measured with an unannounced test of water at the household). 

Further studies are underway, as well as effort to expand the program throughout the world. Chlorine dispensers could be appropriate for up to 2 billion people globally. Scaling up this approach globally could drastically alter the rural water landscape and save the lives of 100,000 – 250,000 children each year. Find out more here.