The impact of waste disposal sites on the local water resources : a case study of the Kiteezi landfill, Uganda

There is a knowledge gap on the extent of the impact of waste disposal sites on water resources in Uganda. This study assessed the effectiveness of the leachate treatment process and the extent of water pollution by the leachate at the biggest sanitary landfill in East Africa, the Kiteezi landfill. Samples of leachate, surface water and groundwater were collected in and around the landfill for four months. Results showed that leachate treatment at the landfill is ineffective for reducing its pollution potential; all the measured parameters, except nitrate and sodium, were above Uganda's National Standards for Effluent Discharge after treatment. Treated leachate had higher pH (9.1 ± 0.10), EC (22,384 ± 879 µS/cm), and concentrations of nitrate (0.469 ± 0.035 mg/L) and potassium (320 ± 30 mg/L) than the untreated leachate, but lower ammonium concentration. The groundwater had very high concentration of ammonium (range: 67.8 – 1313 mg/L), indicating possible pollution by leachate. Additionally, surface water from the point at which untreated leachate enters the Kitetikka stream had values comparable to raw leachate for all measured parameters. The study recommends the improvement of the leachate collection and treatment system to reduce untreated leachate flow into the surface water. Further study into the health impact of the water quality on the local community is essential.