Most WASH impact evaluations measure intervention effectiveness during or shortly after implementation, in a single program or country. The Ripple Effects Study is built for the questions that come after the program ends, and across countries.
The study examines all 16 of Living Water's WASH Program Areas (WPAs) that completed implementation between 2012 and June 2025. By design, the study asks what is still working five-to-twelve years after Living Water exited: a research question the existing WASH evidence base addresses thinly.
The 3ie Evidence Gap Map for WASH identifies long-term sustainability and post-implementation outcomes as one of the most underpopulated cells in the matrix. Ripple Effects fills that cell at multi-country scale.
Phase 2 fieldwork pairs each WPA community with a comparable community in the same country and region where Living Water has not worked. Identifying similar communities is not enough on its own—the study uses propensity score matching (PSM) to formalize that similarity.
PSM estimates the likelihood that a community would have received a WPA intervention, based on pre-intervention characteristics: things like baseline water access, population size, poverty indicators, distance to markets and services, geographic features, and governance context. Communities are matched on these scores, and only pairs meeting accepted balance thresholds are retained for analysis. The result is a matched sample that supports credible causal inference without the barriers of randomization.
Without comparison communities, the study could only describe outcomes. With propensity-score-matched comparison communities, it can attribute change.
Quantitative instruments—household and institutional surveys, water-point functionality assessments, water-quality testing—establish patterns. Qualitative methods—focus group discussions, key informant interviews, and a systematic review of approximately 350 Most Significant Change stories collected across a decade—reveal the mechanisms behind those patterns.
The two are designed to converse with each other from the beginning, not bolted on.
Most WASH studies measure water access, infrastructure functionality, and health outcomes. Ripple Effects measures these and also evaluates church and community engagement, community resilience, and dimensions of human flourishing: the broader outcomes Living Water's WPA model is designed to produce.
This integration places the study in conversation with frameworks like Tearfund's Light Wheel and Harvard's Global Flourishing Study, while keeping infrastructure and health outcomes at the center.
Using the matched samples, the study estimates average treatment effects for key outcomes across WASH access, infrastructure sustainability, and human flourishing. Models use regression adjustment, clustered standard errors at the community level, and country-level fixed effects to isolate WPA impact from country-level variation.
To test the stability of findings, the study runs alternative matching specifications, sensitivity analysis for unobserved bias, and subgroup analyses by gender, geography, and program vintage. Findings are reported transparently with these checks included.
In plain terms: the design lets the study test whether the WPA model caused the outcomes we see in WPA communities, not just that the outcomes are there.
The Ripple Effects Study is designed to assess the long-term outcomes, sustainability, and holistic impacts of Living Water's WASH Program Area model implemented since 2012. The evaluation generates evidence across five domains, asking what has worked, what has endured, and why.
Five domains, in no particular order.
Specific research questions under each domain are being refined with the Academic Advisory Committee and finalized in the Phase 2 Data Collection Plan.
A review of all 16 completed WPAs, drawing on existing evaluation reports, raw datasets, monitoring records, financial data, and the corpus of approximately 350 Most Significant Change stories. Phase 1 produces an interim report and the finalized Phase 2 data collection plan, including six-country selection, indicator set, sampling design, and field instruments.
Households and institutions in each WPA community surveyed alongside their matched comparison communities. Water points assessed for functionality and water quality tested. Focus groups and key informant interviews capture the mechanisms behind quantitative patterns.
All deliverables—interim report, final report, datasets, codebooks, and summary materials—are written to peer-review quality. The study is positioned for academic publication in 2027 and 2028 and is being conducted by Radiant Global Insights, an independent evaluation firm with deep expertise in WASH-sector evaluation and Christian NGO programs. An academic advisory committee supports the study's design, review, and dissemination.
In a contemporary WASH evidence base of more than 350 catalogued impact evaluations, fewer than five are large-scale and multi-country; fewer still incorporate a counterfactual design; and we haven't found another large-scale, multi-country evaluation combining WASH sustainability with an explicit holistic / flourishing measurement framework.
When the findings publish, they will land alongside a small and identifiable peer set, including the World Vision × UNC Water Institute 14-country evaluation, Tearfund's Light Wheel research, and the published Compassion International impact studies that have set the standard for rigorous research from faith-based organizations.
Join the practitioners, researchers, and funders who'll use this study to build on their own work. One email when Phase 1 publishes in August 2026; one when Phase 2 publishes in 2027. Nothing else.
