Sustained effectiveness of chlorinators installed in community-scale water distribution systems in Haiti

In 2012 and 2013, Child Relief International (CRI) partnered with Haiti Philanthropy to install “Chlorinators” in 79 gravity-fed water distribution systems in Southeast Haiti as an emergency response project, followed by a sustainability plan. We carried out an independent evaluation to assess the extent to which Chlorinators were operational and providing safe water approximately two years after installation. We completed 18 randomly selected site assessments, 180 household surveys, water quality testing for Free Chlorine Residual (FCR) and Escherichia coli on water samples from reservoirs, taps, and household stored water, and 24 key informant interviews. None of the systems were functioning 2 years after installation, 3% of household respondents had received information about the Chlorinators, and no community or household water samples had detectable FCR from Chlorinators. However, key informants were largely supportive of the systems. Reasons for non-operation and challenges associated with achieving sustainability are discussed

Evaluation of household drinking water filter distribution programmes in Haiti

Household water treatment can reduce diarrhoeal disease in populations without safe water access. We evaluated five programmes that distributed biosand, ceramic, or Sawyer household water filters in Haiti after the 2010 earthquake. We conducted household surveys, collected water samples, and tested water quality at ~50 houses from each programme. Across programmes, self-reported filter use ranged from 27-78%; confirmed use (met reported use and showed the filter with water in it) ranged from 20-76%; and, effective use (stored water quality was improved to international guideline values using the filter) ranged from 0-54%. More successful programmes: 1) distributed an effective technology; 2) provided safe storage; 3) required cash investment; 4) provided initial training; 5) provided follow-up; 6) provided supply-chain access; 7) targeted households relying on contaminated water sources; and, 8) had experience working in the local context. These findings suggest that well implemented programmes can result in sustained filter use in Haiti

Silver Dissolution and Release from Ceramic Water Filters

Application of silver nanoparticles (nAg) or silver nitrate (AgNO₃) has been shown to improve the microbiological efficacy of ceramic water filters used for household water treatment. Silver release, however, can lead to undesirable health effects and reduced filter effectiveness over time. The objectives of this study were to evaluate the contribution of nanoparticle detachment, dissolution, and cation exchange to silver elution, and to estimate silver retention under different influent water chemistries. Dissolved silver (Ag⁺) and nAg release from filter disks painted with 0.03 mg/g casein-coated nAg or AgNO₃ were measured as a function of pH (5–9), ionic strength (1–50 mM), and cation species (Na⁺, Ca²⁺, Mg²⁺). Silver elution was controlled by dissolution as Ag⁺ and subsequent cation exchange reactions regardless of the applied silver form. Effluent silver levels fell below the drinking water standard (0.1 mg/L) after flushing with 30–42 pore volumes of pH 7, 10 mM NaNO₃ at pH 7. When the influent water was at pH 5, contained divalent cations or 50 mM NaNO₃, silver concentrations were 5–10 times above the standard. Our findings support regular filter replacement and indicate that saline, hard, or acidic waters should be avoided to minimize effluent silver concentrations and preserve silver treatment integrity