Combined Sewer Overflows (CSOs) continue to be a significant source of wet weather flows (WWFs). Traditional technologies exist to address wet weather overflows but are many times cost prohibitive, can yield toxic by-products and in areas of older infrastructure, space for facilities to treat overflows is often limited if available at all. As such more cost effective technologies, requiring less space and producing less harmful by-products are currently being explored. One such possibility for alternative high-rate disinfection has been investigated using peracetic acid. The decomposition of peracetic acid results in only the non-toxic by-products of oxygen, methane, carbon dioxide and water, and the disinfection reaction occurs in a short contact time and with a high kill rate. Thus, this technology can prove not only valuable where space is limited, but is also extremely environmentally sound.