Abstract

Rivers Wouri and Meme are surrounded by streams and wells and serve for irrigation, fishing, domestic purposes and transportation. Water samples were collected from the rivers in February (dry season) and August (wet season) of 2012 at different sites and at different depths and analyzed for some physicochemical properties. This was to study the effect of seasonal changes on the properties and also infer the possible sources of pollution. Water from the other sources was also analyzed. All analyses were done using standard methods. The properties were generally higher during the dry season. Both rivers were acidic. The Electrical conductivities (E.Cs) of River Wouri were generally much lower than those of River Meme with mean values of 2943.0 and 5703.0 μS/cm respectively during the dry season. Ca²⁺/Mg²⁺ ratios for upstream in River Meme were greater than 3 during the dry season. During the dry season, in Wouri at site WO1, Cations and anions decreased with depth, while at site WO7, the same properties increased with depth. For River Meme at site ME1, there was no significant (p<0.01) variation of cations and anions with depth. On the contrary, at site ME8, the anions increased with depth while the cations decreased significantly (p<0.01) with depth. The streams were weakly basic with average pH of 8.3 for those of Wouri and 9.0 for those around River Meme. The streams around River Wouri generally had higher physicochemical properties. Physicochemical properties of the wells of Wouri were generally higher than those of the streams during both seasons. There was a very significant correlation (p < 0.01) between nitrate and choride ions in both rivers during the dry season. Most of the properties were within the levels set by World Health Organization and Environmental Protection Agency (EPA). The water sources are exposed to increases in anthropogenic activities, such as industrial and municipal waste disposal and farming practices. A more stringent legislation about water management, as well as studies about the biological content of the water sources is recommended.

Key words: Physicochemical, properties, Meme, Wouri, rivers, dry season, wet season.