The most widespread disinfection method worldwide. It is often applied as the final treatment step after filtration, but it is also possible as an early treatment step. Centralized installations commonly use chlorine gas. In small communities, hypochlorite solutions or tablet might be more reliable. Local production possible with WATA.
Application of chlorination might be at household level, at small water bodies (e.g. dug wells or small reservoirs) or in a community water system. People working with chlorine need proper training. External support might also include water quality checks.
Environment related issues are estimated to be minimal. No residuals which need to be disposed or treated. Fluctuations in water flow – e.g. as a result of heavy rainfalls - require adjustment in dosing.
Required equipment is simple and reliable. Several conditions important for operation: minimal 30 minutes contact time, residual chlorine between 0.5 and 5 mg/L, pH <8, turbidity <5NTU but ideally <1NTU. Further: refilling chlorine, adjusting and cleaning chlorinator and checking dosing.
Chlorine taste and odor in water may require user education on that it is harmless but that chlorine taste alone is no guarantee for safe water. Possible by-products from disinfection. Limited health risk for people working with chlorine.
No relevant remarks for Chlorine disinfection.