ABSTRACT
Angwan Romi is a place in the Chikun Local Government Area of Kaduna State in Nigeria at 10�25'48 north of the equator and 7�25'12 east of the Greenwich Prime Meridian. Romi River is a body of running water moving to a lower level in a channel on land. It is on Latitude 10.45 decimal degrees, Longitude 7.37 decimal degrees, DMS Latitude 10� 27 min 0 sec, DMS Longitude7� 22 min 0.012 sec. Universal Transverse Mercator (UTM): LS25. The people living in Angwan Romi village and environ use the water of River Romi to supplement their daily water demand which has not been met by government. They may be at health risk as a result of usage of Romi River water. The study was carried out to determine the extent of pollution and self purification of River ROMI. The study covered a distance of 15Km from the point of effluent discharge from the Kaduna Refining Petrochemical Company to the point of outflow into the River Kaduna. The data was collected from July 2009 to February 2010, to capture the dry and wet seasons and repeated again in July 2011 for validation. The number of sampling points was four with six different samples collected for each, with composite sampling at site 1 employed. The samples were analyzed for Dissolved Oxygen (DO), chemical oxygen demand (COD), Biological oxygen Demand (BOD),pH , nitrogen nitrate, ammonia nitrate, phosphates, coliform count (serial dilution), heavy metals, total dissolved solids, temperature, electrical conductivity and discharge and self-purification capacity. The methodologies employed for the analysis were according to the standard methods for the analysis of water and waste water. Most of the water quality parameters were depleted especially at site 3 where a tributary from Nigerian National Petroleum Company Housing estate flows into the river. The observed die-off for bacteria colony count along the Romi River 15 Km course suggested that the stream still can purify itself. The results show deterioration 8 in river water quality for the stretch with only a figment of recovery for some parameters seen at site 4. A model of BOD against Distance was developed from the results obtained. The average DO value was 6.8 mg/L,6.5 mg/L,6.7 mg/L and 6.8 mg/L at sites 1,2,3 and 4 respectively in the rainy season and in the dry season it was 5.5 mg/L,6.0 mg/L,6.5 mg/L and 6.3 mg/L respectively. The de-oxygenation rate was 1.143 d-1. The re-aeration rate was 0.934d-1 which shows that there is appreciable self purification within this 15Km course. Also the results show that the concentration of the heavy metals at each site is in the order of Pb>Cu>Cd. All the parameters monitored indicate serious water quality impairment along the 15km stretch studied. The deterioration is due to discharges from KRPC Plant and NNPC housing estate.