Effect of Raw Sewage on Surface Water Quality in Opobo Town, Nigeria

Abstract

This study investigated the effect of raw sewage on the quality of surface water in Opobo town, Rivers State, Nigeria. The investigation was occasioned by the predominance of direct disposal of raw sewage into surface water bodies in the study area. Opobo town is a coastal community in the Niger Delta area of Nigeria; and in coastal communities, surface water contamination by fecal and organic matter is a primary water quality issue, especially in inland rivers. In the study, samples of surface water were collected with 500ml bottles at seven different points, ranging from the upstream to the downstream of the river. The samples were analyzed for twenty-two different water quality parameters, including turbidity, suspended solids, pH, alkalinity, ammonia nitrogen, dissolved oxygen, biochemical oxygen demand (BOD) and chemical oxygen demand (COD), with the following mean values respectively obtained: 5. 6 NTU, 359.3 mg/l, 5.8, 164.1mg/l, 146.3mg/l, 204.7mg/l and 262.7mg/l. There were also substantial doses of total coliform (172.3 cfu/100ml), E. coli (110.5 cfu/100ml), Enterobacter (106.0 cfu/100ml) and salmonella spp (162.7 cfu/100ml). These results were compared with standard criteria for coastal waters designated for aquatic life, recreation, navigation, and industrial water supply. It was found that the discharge of raw sewage into the surrounding surface waters in the area presented water quality that is injurious to both human and aquatic life. The practice is strongly discouraged and treatment of the sewage before disposal also strongly recommended.

Design of a Prototype Wastewater Treatment Plant for Selected Households

“…The selected households used for this research are situated in Opobo Town, a peri-urban settlement in the Niger Delta area of Rivers State, Nigeria. According to [1], Opobo is located at the southern part of Nigeria just beneath Ikot Abasi, Akwa Ibom State. It lies between latitude 4° 30' 41.11" N and longitude 7° 32' 24.32" E. The town is inclusive in the total area of 130 km 2 of the local government area, and has an average elevation of 4m above sea level.…”

“…According to [1] "untreated wastewater results in high intensity ascariasis infections comprised of cognitive impairment, severe dysentery and anemia". Other diseases related to this activity are "schistosomiasis, trachoma, trichuriasis, hookworm disease, malaria, yellow fever, filariasis, dengue, hepatitis A and E, typhoid, arsenicosis, fluorosis and legionellosis".…”

“…Nutrients contained in human excreta produce phosphorus and nitrogen in the river. This increases the nutrients and result in algal blooms, loss of oxygen, fish kills and loss of biodiversity, amongst other problems" [1].…”