Evaluation of the Water Quality of River Kaduna, Nigeria Using Water Quality Index

Fj Ogbozige,A Giwa,Sb Igboro,Db Adie

doi:10.4314/jasem.v21i6.21

Abstract

Twelve (12) water quality parameters (turbidity, TDS, pH, Cl- , EC, DO, BOD5, COD, total nitrogen, total phosphorus, Fe and Mn) were analyzed in River Kaduna, Nigeria on a monthly basis for a period of one year in 15 sampling locations using standard methods. The data obtained were used to develop Water Quality Index (WQI) across the 15 sampling locations. The WQI revealed that the water quality of 4 sampling locations were poor as their index values ranged between 17.77 to 25.47. On the other hand, the generalized water quality of the remaining 11 sampling locations was marginal as the index values ranged between 44.95 to 60.80. The index values of the various sampling locations were thereafter used as weights in mapping the WQI of the entire sampled portion of the river using Inverse Distance Weighted (IDW) interpolation method. The WQI of the entire river was suggestively ranked marginal as 11 sampling locations out of 15 (73.3%) fell into the marginal category. Hence, regulatory agencies were advised to check the anthropogenic activities along the watershed with more emphasis at the hot spot areas or locations that recorded poor WQI. Key Words: WQI, Canadian, Mapping, Sampling, Locations.

Highlights

Thereafter, the results obtained were ranked into five categories as recommended by the Canadian Council of Ministers of Environment (CCME, 2001). These five categories for the assessment and protection of aquatic environment are as follows; Excellent: (CCME Water Quality Index (WQI) Value 95-100) – Water quality is protected with a virtual absence of threat or impairment; conditions very close to natural or pristine levels
Good: (CCME WQI Value 80-94) – Water quality is protected with only a minor degree of threat or impairment; conditions rarely depart from natural or desirable levels
Based on the results obtained in this research, it could be concluded that the WQI of River Kaduna on the Canadian scale is mostly marginal

Summary

Introduction

The Canadian Council of Ministers of Environment Water Quality Index (CCME WQI) was developed by substituting the values of F1, F2 and F3 into the Equation (7) given by CCME, 2001. These five categories for the assessment and protection of aquatic environment are as follows; Excellent: (CCME WQI Value 95-100) – Water quality is protected with a virtual absence of threat or impairment; conditions very close to natural or pristine levels.

Results

Conclusion