Background <p>Water is important for humans with roles of maintaining body functions such as temperature and preventing dehydration. However, studies on water intake among university students is limited within Ghana. This study aimed to understand motivators and barriers to water intake and observe variations with regard to water intake by body mass index categories.</p> Methods <p>University public health nursing students (<i>N</i> = 16) aged 18–25 were selected. The students were grouped using the WHO body mass index classification; underweight (&lt; 18.5&#xa0;kg/m²), normal (18.5–24.9&#xa0;kg/m²), overweight (25.0–29.9&#xa0;kg/m²) and obese (≥ 30.0&#xa0;kg/m²). Interview guides were used to conduct in-depth interviews. The transcribed interviews were analyzed thematically by identifying codes which were organized and arranged based on shared patterns to form sub-themes and further grouped under the main themes identified in advance using the study guide.</p> Results <p>Factors that motivated or obstructed students from taking adequate water were categorized according to the socio-ecological model. Motivators to water intake were at the individual level (physical activity/eating behaviors, knowledge of health benefits on water), physical environment level (weather), community/university level (health literacy) whilst barriers to water intake were individual (physiological, poverty), social/interpersonal (desire for sugar-sweetened beverages), physical environment (cost of preferred brands, geographical access/availability to water) and community/university (lack of resources, non-availability of sanitary facilities) levels. Intake of water as reported, showed a much poorer intake by the obese, overweight and underweight students.</p> Conclusions <p>The findings should initiate a dialogue on the need to engage students and other stakeholders on adequate water intake.</p>