Classification of river water quality in Ogun and Ona River Basins, Nigeria using CCME framework: Implications for sustainable environmental management

Figures & data

Figure 1. Study location in Ogun and Ona Basins.

Figure 2. Land Use map of Ogun and Ona Basins.

Figure 3a. pH and EC across the rivers.

Figure 3b. Biochemical oxygen demand and dissolved oxygen in rivers across the Basins.

Figure 3c. TSS and turbidity in rivers across the basins.

Figure 3d. Nitrogen characteristics in rivers across the Basins.

Figure 3e. Phosphorous characteristics in rivers across the basins.

Figure 3f. Heavy metals characteristics in rivers across the basins.

Figure 3g. Microbiological pollutants in rivers across the basin.

Table 1. Quality scores of the three water quality indices across the locations

		Locations
WQI (scores)	OG1		OG2	OG3	OG4	OG5	OG6	OF1	OF2	OF3	OF4	IB1	IB2	OM1	OM2
HWQI	26		26	24	25	24	24	29	25	21	24	42	22	24	21
EWQI	52		51	76	48	48	40	50	46	45	49	42	51	44	46
AGWQI	32		43	31	43	3	32	31	59	30	29	28	31	30	43
WQI (scores)	OP1		OP2	EWE1	EWE2	ON1	ON2	ON3	ON4	ON5	OGP1	OGP2	OGP3	OGP4
HWQI	21		24	21	21	21	21	21	23	42	21	21	22	21
EWQI	36		42	45	43	45	40	45	48	44	43	41	42	42
AGWQI	28		31	32	30	31	34	31	30	31	31	29	30	31

Notes: Poor: 0–44; Marginal: 45–64; Fair: 65–79; Good: 80–94; Excellent 95–100.

Figure 4. Spatial characteristics of health water quality in Ogun and Ona Basins.

Figure 5. Spatial characteristics of environmental water quality in Ogun and Ona Basins.

Figure 6. Spatial characteristics of agricultural water quality in Ogun and Ona Basins.

Figure 7. Population distribution across the study area.