Introduction: CKD unrelated to diabetes or hypertension is epidemic in Central America. Sugarcane workers are among the most affected with heat stress and dehydration suggested as central elements. An intervention on these factors accompanied by productivity improvements was piloted in El Salvador during the 2014-15 harvest. Methods: The intervention adapted the OSHA Water.Rest.Shade (W.R.S.) hot work guidelines mid-way through the harvest for one cutting group. Water was provided in individual backpacks along with mobile shaded rest areas and scheduled rest periods. Ergonomically improved machetes and efficiency strategies were implemented for productivity. Health data (anthropometric, blood, urine, questionnaires) were collected 4 times in six months. Daily wet bulb globe temperatures (WBGT) were recorded. The employer provided production records. Results: WBGT exceeded OSHA's limits for continuous work from 9 AM onwards and exceeded OSHA's highest limit (requiring 75% rest/hour) for 14% of hours. Post-intervention self-reported water consumption increased 25%. Symptom surveys suggested reduction in most heat stress and/or dehydration symptoms. Daily production increased almost 50% exceeding productivity of most other cutting groups. Focus groups reported positive perception of both the W.R.S. program and the productivity improvements. Preliminary analysis of kidney function indicates stable or slightly improved function following the intervention. Conclusion: A W.R.S. intervention is feasible for manual sugarcane cutters. The intervention demonstrated reduced impacts of heat stress while the improved machete and change in cutting strategy also improved productivity. Initial adoption by participants and the company is encouraging, as is interest demonstrated by labor ministries of El Salvador and Costa Rica.