ANALYSIS OF WATER QUALITY DETERIORATION IN NWORIE RIVER, OWERRI- IMO STATE, SOUTHEAST, NIGERIA

Abstract

Due to indiscriminate activities of man through sand excavation, sand mining and illegal waste disposal within the watershed the study evaluated the effect of these activities on selected water quality parameters of Nworie River in Owerri -Imo State, Southeast Nigeria. The study area was divided into Upstream, Midstream and downstream. The river was sampled and the raw data from water sampling were subjected to laboratory analysis; results obtained were matched with standards. The results showed that the average pH of the river was 7.4; upstream and midstream had higher pH values than the downstream with low pH and these were within the permissible limit. Biological oxygen Demand (BOD) of the river were 75mg/l, 60mg/l and 56mg/l at the Upstream, Midstream and downstream with an average value of 64 mg/l . The river had a mean turbidity value of 76NTU and mean Total Dissolved solids (TDS) value of 272mg/l which were above the permissible limit. Calcium (Ca2+) did not exceed the standard limit while magnesium exceeded the standard limit by 68% at the Upstream. Nworie river had mean water conductivity value of 93S/cm; water conductivity at the Midstream and downstream were within the permissible limits while the Upstream had 6% increase above the acceptable limit. It was observed from this study that Nworie river exhibited three different colours of light-green, dark-green and brownish-muddy colour respectively at the Upstream, Midstream and Downstream which could be attributed to the level of erosional deposits and sediment loads from the degraded watershed. Further degradation of the watershed should be avoided by practising good soil conservation measures, ensuring that indiscriminate activities of inhabitants of the area are stopped and since environmental balance, land degradation, water management and food security are strongly linked, each must be addressed in the context of the other to have a measurable impact to the society.