Household Water Quality: Effectiveness of Chlorine Disinfection

This indicator measures the effectiveness of efforts to disinfect public water supplies and maintain adequate levels of free residual chlorine (FRC) all the way down to the point of consumption at the household. A household is generally defined as one or more people living in shared space (a physical structure or compound) and sharing critical resources such as water, hygiene/sanitation facilities, or food preparation areas. ""Drinking water supplies"" at household level may be stored water, or where households have a piped connection directly into the structure or compound i.e. a tap. For households that do not have a tap, water stored for the purpose of drinking should be tested for FRC. For households that do have a tap, water directly from the tap as well as any water stored for the purpose of drinking should be tested.

The presence of FRC indicates that:
1. a sufficient amount of chlorine was added to the water to inactivate most of the pathogens that cause diarrheal disease; and
2. Some extended protection is provided (relative to the quantity of FRC) to prevent recontamination during transport home and storage of water in the household.
Method: Statistically valid, beneficiary based survey with household-level water quality testing survey. Enumerators and staff must be trained and proficient to collect and analyse samples for FRC. You should also develop an outreach plan in advance that addresses local cultural sensitivities and any potential concerns households may have related to having their water tested. Equally you need to have a plan in place to report back to households the results of the water quality testing
Calculation: the percent is derived by dividing the number of households surveyed whose drinking water supplies have FRC ≥ 0.2 mg/L by the total number of households surveyed in the target population. Both numerator and denominator are reported as well as the percent.
Numerator: number of households surveyed whose drinking water supplies have FRC ≥ 0.2 mg/L
Denominator: number of households surveyed in the target population

RECOMMENDED SURVEY QUESTIONS (Q)

Water quality samples taken as part of a representative household survey; households to give their consent to samples being taken away for analysis; outreach plan in place to address any concerns, and to report back to households