Borehole water is one of the major sources of potable water in most developing countries of the world. Therefore, it becomes imperative to evaluate the continuing portability of these sources of water to the populace. The present study was undertaken to appraise the water quality of selected boreholes in Owerri Metropolis using the water quality index (WQI) method. Samples were collected from five different locations under stringent protocols. The water samples were analyzed for selected physicochemical properties and compared with WHO permissible limits and American Public Health Association. Results showed that the assayed parameters were within WHO permissible limits except Turbidity in Locations 2, 3 and 4. Water quality index ranged from 24.91 to 70.06. This study revealed that the investigated borehole waters are mostly portable and can be consumed. Nonetheless, the sources identified to be of poor quality should be treated before consumption.

The research was intended to study the influence of human and industrial activities on the Orashi River. Three groups are observed to have impacted the environment – Oil/gas industries, tyre burning (smokes and ashes) released during roasting of slaughtered animals in abattoir, untreated human and animal waste from settlers and the abattoir.  The study was carried out from September 2019 to August 2020. The mean concentrations of the parameters studied in some samples were close to or exceeded World Health Organization (WHO) and Nigerian Federal Ministry of Environment (FMEnv) recommended limits for drinking water and seafood. The results from this study have provided information on the heavy metals profile on the surface water and sediment of the river.  Essential heavy metals detected in water were in the range of Cu (1-5.4mg/l), Zn (1-4.4mg/l) and Fe (0.1 – 1.8 mg/l) which were within the WHO (1989), USEPA (1986), FEPA (1999) permissible limit of 3mg/l. The non-essential metals investigated were Cd, Cr and Pb but only Cd was detected. Cd levels (0.1-0.8mg/l) were slightly high, above the  permissible limit of 0.01mg/l. Heavy metals in sediment were higher than those in the water body, occurring in the sequence Zn>Cu>Fe >Cd. The ranges were Zn (1.4-5mg/kg), Cu (0.8-3mg/kg), Fe (0.4-4.9mg/kg) and Cd (0.5-1.8mg/kg). All relationship were statistically significant (p=0.05). With regards to seasonal variation, dry season recorded higher values than rainy season. Heavy metals in sediment were higher than those in the water body, occurring in the sequence Zn>Cu>Fe >Cd. The ranges were Zn (1.4-5mg/kg), Cu (0.8-3mg/kg), Fe (0.4-4.9mg/kg) and Cd (0.5-1.8mg/kg).  Cd and Fe in water and sediment have higher concentration during the dry season while Cu and Zn are higher during the rainy season in both parameters during the study period. Increased level of pollutants in the Orashi River may have significant effect on the ecological balance of the River. Again, long term bioaccumulation through food chain is a major concern as this study had revealed that sediment act as sink of pollutant loads than the water samples.

Length-weight relationship and condition factor are important in fishery assessment studies since it provide information about the growth of the fish, its general wellbeing and fitness in aquatic habitat. LWRs for 2 fish species –Clarias gariepinus (Burchell 1822) and Oreochromis nilotica (Linnaeus 1758) collected from Orashi River were established and their growth condition was evaluated. The study was carried out from September 2019 to August 2020. The biometric measurement (length/weight) shows that the weight of the fish increased in proportion to its length as indicated by the slope (b) of the relationship.  The mean value shows strong relationship because coefficient of determination (R2) is >0.5 and range from 0.795-0.985. Higher values of both length and weight were recorded for Catfish over Tilapia. The results indicated that almost all the fish sampled exhibited a positive allometric growth and trended to grow bigger. All relationship were statistically significant (p=0.05). The mean Fulton’s condition factor (K) of the fish range from Catfish (1.24-1.80) and Tilapia (1.5-3.7) in the 5 stations sampled. The result showed that Tilapia had a high mean range and therefore was in better conditions than the Catfish. This gives information on the food supply, timing and duration of breeding cycle. The indices may also be used in the general assessment of the “well being” of a fish [1]. Multiple comparison tests using Turkey Kramer showed that the condition factor of Catfish from Okwuzi (station 1) was significantly different from that of Ndoni and Omoku but Ebocha and Obrikom was not significantly different from each other. With regards to seasonal variation, dry season recorded higher values than rainy season.

The research was intended to study the influence of human and industrial activities on the Orashi River and two bony fish (Clarias gariepinus and Tilapia nilotica). Three groups are observed to have impacted the environment – Oil/gas industries, tyre burning from abattoir, untreated human and animal waste from settlers and the abattoir.  The study was carried out from September 2019 to August 2020. The mean concentrations of the parameters studied in some samples were close to or exceeded World Health Organization (WHO) and Federal Ministry of Environment (FMEnv) recommended limits for drinking water and seafood. The results from this study have provided information on the heavy metals profile on the fish of the river.  The level of heavy metals in the muscle of Catfish and Tilapia showed a range of Cadmium in Catfish (1-3.9mg/kg and Tilapia (0.1-4.2mg/kg) with the highest level occurring in station 2 (3.47mg/kg for Catfish and 3.39mg/kg for Tilapia) which is high with regard to FAO 19835, FAO/WHO 10896, EEC 20054 permissible limit of 0.01mg/l and USEPA SQG (1mg/kg) level in seafood. The levels of essential heavy metals in fish muscle were Copper (Catfish-10.9-33mg/kg, Tilapia -17.3-40.6mg/kg), Iron (Catfish-1.0-2.5mg/kg, Tilapia -0.1-5.6mg/kg) were within the FAO 1983 permissible limit while Zinc (Catfish-22-213.2mg/kg) and Tilapia (30.1-196mg/kg) exceeds the limit in some stations. Catfish muscles recorded higher mean value (127.12mg/kg) for all heavy metals than tilapia (44.03mg/kg) and the sequence is Copper > Zinc > Iron > Cadmium. The concentration of heavy metals in Orashi River is in the sequence: Sediment > Catfish > Tilapia >Water. The Total Heavy metal concentration in muscle of Catfish (0.5-1.8mg/kg) and Tilapia (0.1-3.8mg/kg) were within permissible limit.