Shared Waters, Shared Opportunities and Shared Threats; The Case of Chunga River, Lusaka, Zambia
Water is a scarce and a vulnerable resource. The use of water in an environmentally sustainable manner can help achieve global development. This is because an environment with poor water quality is bound to encounter catastrophic problems and subsequently derail global development. 'Shared water and shared opportunities' was the global theme of the World Water Day celebrations for 2009. This was the inspiration to doing this study. The study is premised on the fact that the water resources that are in the Chunga River, a local tributary of the Mwembeshi River in Lusaka District are important for human use while at the same time depend on waste water from Lusaka Water and Sewerage Chunga Treatment plant for much of the flow. The waters in this river are finite and under threat due to poor sewer handling. This study investigated and analyzed secondary and primary data in coming up with conclusions and recommendations. The methodology used in executing this study was first to analyze existing data on the Chunga River and the actual sampling in the field. The results obtained showed that Chunga River water is poor when analyzed from a point just after the discharge of effluent at the treatment plant. This shows that the water in many ways does not meet the recommended standard. Specifically, Biological Oxygen Demand, Chemical Oxygen Demand and Dissolved Oxygen and bacteria load (Total and Faecal coliforms) did not meet the statutory standard recommended for effluent. The average demand for BOD at Chunga LWSC discharge point was 185mg/l which is above the statutory ECZ limit of 50mg/l. Similarly, the average demand for COD for the period under review was 409mg/l, a figure which is about four times the ECZ statutory limit of 90mg/l. The dissolved oxygen levels remained below the 5mg/l statutory limit for most parts of the dry season while during the rainy season; the levels barely equaled the statutory limit. The microbiological quality was also found to be above statutory limits in both the LWSC and research results. The pH value however remained between 7 and 8 which is favourable condition for most aquatic life provided other conditions are also favourable. From the results, quality of the water is poor as indicated above at the discharge and improves at it flows down stream. It is important to improve the treatment capabilities of the Chunga Treatment plant and in the meantime cordon a considerable distance along the river immediately after the discharge to avoid sorption of concentrated contaminants right after discharge. The study also revealed that an average of 46 million cubic meters of water was discharged annually between 2007 and 2009 portraying the water potential of the Chunga River.
Waters , Shared Waters