SERVICE LINES - THEIR EFFECT ON MICROBIOLOGICAL QUALITY

The influence of service lines on the microbiological quality of drink ing water was investigated. The microbial water quality in domestic se rvice lines was found to differ from that in the main pipes of the dis tribution system. Differences in bacterial counts from the first flush of the service line and from the main pipe were generally more pronou nced in service lines located near the plant. After a thorough flushin g of the service Line, however, tap water quality was found to be equi valent to that in the main pipe. Bacteriological parameters studied we re total direct count after acridine orange staining heterotrophic pla te counts, total coliforms, and Aeromonas. Physicochemical parameters measured included temperature, oxidant residual, and total, dissolved, and biodegradable organic carbon. Lead and copper concentrations were determined in the first flush after flushing the service line, and in the water samples from the main pipe.