Rainwater Quality Assessment in Uyo Metropolis using Water Quality Index

Abstract

Rainwater is source of water for drinking and for other purposes in Akwa Ibom State. Water quality index (WQI) was used to assess the quality of rainwater in Uyo metropolis, and pollution index to identify the individual parameter that was of risk. Twenty-two physiocochemical parameters and seven toxic metals were determined in rainwater from six locations, using standard methods. The results were compared with WHO Limits. With the exception of temperature, pH, Ni, Cd, Pb, and Fe, others were within the WHO limits. Pollution index of parameters revealed no pollution to 50% of the parameters, slightly polluted to 9%, strongly polluted to 9% and seriously polluted to 32% of parameters. The overall mean water quality index was 1202, with pattern in the order: Urua Akpan Andem < Champion breweries < Abak road < Aka road < Plaza <Udo Udoma road; and confirmed the water unfit for drinking, due to the presence of high levels toxic metals. Suitable and efficient purification method is required before rainwater could be used for drinking purpose in the urban city.