Practical applications of turbidity monitoring

To take the use of turbidity measurements to a level at which accuracy is critical without the support of quality assurance‐quality control would be inappropriate. The Philadelphia Water Department (PWD) has expended considerable effort to achieve a voluntary 0.1‐ntu turbidity goal. This was motivated in large part by heightened concern about Cryptosporidium, by the expectation of changes in regulatory requirements under the Safe Drinking Water Act, and by voluntary participation in the Partnership for Safe Water. This article summarizes PWD's understanding of, concerns about, and perspectives on the practical applications of turbidity monitoring.