Measuring domestic water use: a systematic review of methodologies that measure unmetered water use in low‐income settings

Objective To present a systematic review of methods for measuring domestic water use in settings where water meters cannot be used. Methods We systematically searched EMBASE, PubMed, Water Intelligence Online, Water Engineering and Development Center, IEEExplore, Scielo, and Science Direct databases for articles that reported methodologies for measuring water use at the household level where water metering infrastructure was absent or incomplete. A narrative review explored similarities and differences between the included studies and provide recommendations for future research in water use. Results A total of 21 studies were included in the review. Methods ranged from single‐day to 14‐consecutive‐day visits, and water use recall ranged from 12 h to 7 days. Data were collected using questionnaires, observations or both. Many studies only collected information on water that was carried into the household, and some failed to mention whether water was used outside the home. Water use in the selected studies was found to range from two to 113 l per capita per day. Conclusion No standardised methods for measuring unmetered water use were found, which brings into question the validity and comparability of studies that have measured unmetered water use. In future studies, it will be essential to define all components that make up water use and determine how they will be measured. A pre‐study that involves observations and direct measurements during water collection periods (these will have to be determined through questioning) should be used to determine optimal methods for obtaining water use information in a survey. Day‐to‐day and seasonal variation should be included. A study that investigates water use recall is warranted to further develop standardised methods to measure water use; in the meantime, water use recall should be limited to 24 h or fewer. Objectif Présenter une analyse systématique des méthodes de mesure de l'utilisation domestique de l'eau dans les milieux où les compteurs d'eau ne peuvent pas être utilisés. Méthodes Nous avons systématiquement cherché dans les bases de données EMBASE, PubMed, Water Intelligence Online, Water Engineering and Development Center, IEEEXplore, Scielo et Science Direct, pour des articles rapportant sur des méthodologies de mesure de l'utilisation de l'eau dans les ménages où l'infrastructure de compteur d'eau était absente ou incomplète. Une revue narrative explore les similitudes et les différences entre les études