The study will be conducted in four districts in the Terai region, Rautahat, Siraha, Sarlahi, and, Saptari. The ongoing first phase of the study includes collecting and analyzing secondary data on toilets design, the number of toilets constructed, leaching risks, source water proximity in the districts mentioned above. In addition, the data on ODF toilets from the Department of Water Sewage and Supply (DWSS), regional or governments, or survey databases like Multiple Indicative Cluster Surveys (MICS) are being collected. The second phase, which is running in parallel with the first phase, includes surveys on selected households on toilet use, hygiene behavior, and health hazards related to diarrheal diseases. The survey questionnaire is being designed, and it will be conducted in early August 2021. The project's third phase will include water quality testing around the survey households for possible fecal indicators using Compact Dry plates.