Climate change contributes to drought, causing damage to smallholders who rely on rainfed farming, threatening crop productivity and food security. Female farmers are more devastated due to limited access to agricultural resources. This study set out to investigate water scarcity and productivity to identify sustainable, accessible rainwater harvesting technologies (WHTs) and to boost food production and security by upgrading rainfed agriculture. We used primary data from Kakamega County, Kenya. Descriptive and econometric analyses indicate gender inequality was notable, with higher percentages of women lacking knowledge of WHTs. Small percentages of women inherit land from their fathers or husbands, thereby constraining them from adopting WHTs and sustainable farming practices and preventing access to bank credit. Ninety-six percent of participants expressed interest in WHTs, although 68% reported high installation expenses and only 4% were aware of efficient rainwater usage methods. Estimated coefficients of drought (8), access to credit (28), and extension visits (23) increased the adoption of WHTs, while irrigation (15), mobile phones (27), and women cooperative membership (19) boosted food security (parentheses represent percentage points). Policymakers, governments, development agencies, and civil societies should implement laws favoring gender equality in land inheritance rights. They should support water storage facilities, increase the number of agricultural extension officers (more female officers), offer training in WHTs and sustainable farming practices, and create incentives that mobilize farmers to join cooperatives and water associations. These would subsequently improve crop productivity due to farmers planting crops throughout the year, thereby engendering food security. Drought duration (in months) varies across the villages, requiring local context-specific solutions.