Terrumun Kenneth Kwadzah¹, Oliver Terna Iorhemen^1,

The discharge of untreated high-strength wastewater into water bodies results in water quality deterioration of the receiving waters. The aim of this study was to assess the impact of abattoir wastewater discharge on the water quality of river Kaduna, Nigeria. Water samples were collected from river Kaduna at three points: 100m upstream of the abattoir discharge point, at the discharge point, and 100m downstream of the discharge point for a 6-month period (July- September in the rainy season and October-December in the dry season). Physico-chemical analyses were conducted on the collected samples in the laboratory using standard methods. The pH was within a fixed band of 6-8. The downstream 5-day biochemical oxygen demand of the receiving river water increased significantly to 75% in July and up to 192% in December. Suspended solids, chemical oxygen demand, ammonia-nitrogen, total nitrogen and total phosphorus followed a similar trend. Dissolved solids, dissolved oxygen, nitrate-N, iron, zinc and cadmium also increased appreciably. The downstream levels of these parameters were higher than their corresponding upstream values, indicating that the discharge of the abattoir wastewater into the river has negatively impacted the river water. The dilution of the waste in the river water was not enough to reduce them to acceptable levels. This research demonstrates that abattoir wastewater impacts the river water negatively. The findings can be useful in identifying water quality problem areas and planning of engineering interventions as well as basis for legislation.

abattoir wastewater, impact, river Kaduna, pollution, water quality