Studies on the physicochemical and bacteriological properties of some semi-public Swimming pools in Makurdi, Nigeria

Recreational waters are routes of transmission for most water-related illnesses. In this study, the water quality of five selected swimming pools (SP) was examined after disinfection prior to bathing and after bathing by swimmers. SP sampling was carried out weekly for 4 weeks between August and September in Makurdi, Nigeria. Bacterial loads and physicochemical parameters were determined using standard and standard analytical methods, respectively. Most of the physicochemical parameters analyzed were within recommended limit except for residual chlorine, turbidity, dissolved oxygen and total dissolved solids exceeding the permissible limit in some SPs before and after bath. Total heterotrophic count before bath ranged from 2.1 × 107 to 10.9 × 107 cfu/ml and 4.2 × 107 to 17.6 × 107 cfu/ml after bath. Some SPs revealed Salmonella-Shigella spp. contamination before and after bath. Total coliforms (TC) ranged from 0-27 MPN/100 ml and 0-43 MPN/100 ml before and after bath respectively, while faecal coliforms (FC) ranged from 0-9 MPN/100 ml before bath and 0-21 MPN/100 ml after bath. Two of the studied SPs significantly increase in TC (150 and 86%) and FC (105 and 22%) after bath. The results suggest that the possible routes for pools contamination include source of water, inadequate disinfection process, faecal discharge and bather density.