This study brings together the level of objective knowledge on water-related issues and other variables of psychological and situational nature. A random sample of 459 participants was employed, selected proportionally based on sex and age. In this sample, knowledge on the water-related issues tended to be low, particularly related to the direct source of water in the household, the type of services involved in the management, and consumption itself. In order to understand both the relationship with knowledge on water and the relative importance of all the other factors, a regression model was formulated. The highest standardised effect was for sex, followed by occupation, political leaning, and water-related emotions. The best level of knowledge was attained if the residents were male, if they were actively employed or unemployed, if their political leaning was towards the left, and if they demonstrated greater emotional involvement with the water use. Consequently, the design of programmes would need to consider that the information flow must be greater for citizens as a whole, particularly for certain groups such as women and students. It should contribute to the realistic perception of water as a problem and to seek emotional involvement.
Keywords: psychological factors; social perception; urban population; water domestic consumption; water objective knowledge; water-related issues.