The New Castle Consolidated Water District purchases its Raw Water from the NYCDEP through its connections to the NYC Aqueduct System. Every year the Water Unit of the Town of New Castle Department of Public Works publishes an Annual Water Quality Report (AWQR) that summarizes the overall water quality of the drinking water in Town from the previous year. These AWQRs appear on the Town's website.
Once the Millwood Water Treatment Plant (MWTP) receives water from the New York City Aqueduct System; the Raw Water is processed through an extremely fine-tuned water treatment plant. Basically the Raw Water is cleaned (by the removal of greater than 99.9 % of the particulate matter (turbidity) in the water while the water proceeds through two different stages of disinfection (ozonation and minor chlorination). New York City residents, on the other hand, do not receive this highly clarified water. New York City's water is merely disinfected by UV treatment, without the benefit of filtration.