Background: Workers in the sewage industry are particularly vulnerable to infections associated with human excreta and waste water, including a wide spectrum of water-related diseases. Aim: To evaluate the effect of supportive information regarding water-related diseases health risks prevention among Fayoum city sewage workers. Design: A quasi-experimental research design was utilized. Setting: The study was conducted at three locations in Fayoum city, which are affiliated to Fayoum drinking water and Sanitation Company. Sample: A stratified sample was used, and 114 sanitation workers were recruited based on the inclusion criteria. Tools: two tools were utilized: Tool I: An interviewing questionnaire consisted of five parts (Socio-demographic and occupational characteristics of sewage workers, the provision of health care services, personal protective equipment (PPE) availability, and self-reported health effects based on worker health history), and A structured questionnaire to assess workers' knowledge regarding water-related diseases. Tool II: self-reported practice checklist concerning workers safe health practices. Results: Revealed a significant improvement in sewage workers knowledge. Where the mean of total knowledge scores of them had significantly improved from 28.78±9.91 pre- test to 46.13±4.96 immediately post-test, and there was a statistically significant difference in the total practices regarding water-related diseases' health risks prevention pre and post-application of supportive information. Conclusion: The study concluded that the application of supportive information was effective in improving sewage workers' knowledge and practices regarding water-related disease health risk prevention. Recommendation: Periodic educational sessions on various water-related diseases health risks prevention, first-aid, safety measures, and personal protective equipment training.