Title: ASSESSING THE IMPACTS OF CATFISH POND EFFLUENTS DISCHARGES ON SUBSURFACE WATER IN NIGERIA
Abstract: This study assessed the impact of catfish pond effluents discharges on the quality of subsurface water where five catfish farms were located. Water samples were taken at depth of 0 – 200 cm and at intervals of 50 cm distance of each water source from neighbouring fishponds. Water quality indicators- pH, Turbidity (TB), Total dissolved solids (TDS), Total alkalinity (TA), Total hardness (TH), Specific conductance (SC), Chloride (Cl), Total nitrogen (TNO3), iron (Fe), Manganese (Mn), biological oxygen demand (BOD5) and phosphate (PO4) were measured. The samples were examined in accordance with the standard methods described by the American Public Health Association (APHA). The data were analysed using descriptive statistics. Results showed that 100% of the water samples tested recorded turbidity levels exceeding the safe limit for drinking water. In 75% of the samples, iron concentration exceeded the recommended limit of 0.3mg/l for drinking water. The pH and manganese levels of water were between 7.70 – 8.10 and 0.11 – 0.12 mg/l respectively and as such are within permissible range of 6.5 – 8.5 and 0.2 mg/l respectively for drinking water. Other parameters except BOD5 did not exceed the recommended limits for drinking water. The water quality in swampy areas was significantly higher (p ≥0.05) than that of the inter-land. The discharge of catfish pond effluents did not significantly impact water quality for fish production, but it rendered water unsafe for human consumption. The findings indicated that improper discharge of catfish pond effluents into the environment could result into environmental contamination and thus render water unsafe for human consumption. Hence, subsurface water located close to neighbouring fish ponds should be treated before its usage for human consumption.