International Journal of Scientific Research and Engineering Development

Treatment of wastewater in the developing world is rarely practiced due to unavailability of treatment plants and high cost of treatment. Hugely polluted wastewater with high fecal coliform levels is a public health risk, increases cost of wastewater treatment, causes eutrophication, and ecosystems deterioration. There exist numerous studies on wastewater treatment but little oe no studies examined the effect of waste stabilization pond (WSP) operating capacity on its efficiency. This study employed on-site and laboratory investigations to explore the University of Ghana’s waste stabilization pond (WSP) efficiency, and the Onyease stream water quality after wastewater discharged into it. The Legon WSP system has a designed capacity of 8, 550 m3, initially utilized 1, 300 m3, and currently treats at 3,500 m3/day. Though there exist works on WSPs in Ghana, no studies have examined the effect of WSP’s operational variation on efficiency. Bi-monthly samples were taken from the influent, anaerobic, facultative, and two (2) maturation ponds in series and analyzed in the laboratory. The study demonstrated the high efficiency of Legon’s WSP in wastewater treatment and achieved over 94% removal of TSS, turbidity, BOD, and COD, and more than 96% reduction in NH3--N and PO4—P concentrations, but maintained pH and temperature within Ghana’s EPA standards. Microbiological analysis showed significant reductions in coliform counts and improved microbial water quality. Sludge assessment revealed efficient operation in the anaerobic pond (28.1%) and maturation pond 2 (27.1%), whereas the facultative pond (34.2%) and maturation pond 1 (33.9%) required desludging. More frequent desludging and expansion of the Legon WSP system to receive additional wastewater inflow are recommended in the short and long terms respectively. Overall, the WSP effectively enhanced water quality and ensured robust nutrient and microbial removal. Measures such as chlorination and ultraviolet (UV) treatment are recommended to improve the efficiency and meet the standard microbial limits of Legon’s WSP.