Human water contact patterns were studied in two resettlement communities at the Oyan Reservoir in south-west Nigeria in all four seasons in 1991 and 1992. Water contact was most intensive in the afternoon and in the hot dry season, but different types of activities exhibited different daily and seasonal patterns. Both communities were highly endemic for urinary schistosomiasis. However, knowledge regarding schistosomiasis transmission was very limited and the infection was, in spite of a very high frequency of blood in the urine, not considered a major public health problem. Most water contacts were of either a recreational (swimming, bathing) or economic (fishing) nature, and age- and sex-related patterns were evident. The overall level of exposure peaked in the 10–14 years age group but water contact of an economic nature peaked in the 20–39 years age group. Females had generally more water contact than males.