The Moon Township Municipal Authority (MTMA) provides water service to 8,500 water customers in Moon Township; 9,500 sewage customers in Moon, Crescent and South Heights; and wholesale sewage treatment services to three other townships. MTMA originally was a well only water supplier. To meet growing demand raw water from the Ohio River was added in 2003. At that time, MTMA installed an early technology ultraviolet light (UV) system to prevent microorganism reproduction. MTMA wanted to have the same confidence in their water supply as when they only used wells. UV provides an additional disinfection barrier, however, EPA guidance for validation of UV systems was not yet available. 

Challenge

MTMA was upgrading their drinking water treatment plant because some treatment tanks and the UV system were near the end of their useful lives. MTMA also desired to install plate settlers to optimize solids settling. Though not required to upgrade the UV system, MTMA wanted to have a new reliable validated UV system. Having a validated UV system allows reduction in chlorine feed. The upgrade also posed footprint related challenges. Instead of having four small units, one on each filter without redundancy, the Evoqua system installed provides a larger unit to treat flow from all four filters and a redundant second unit in parallel. MTMA was required to submit the improvement plan as well as the UV validation information to the Commonwealth of Pennsylvania, Department of Environmental Protection Bureau of Safe Drinking Water for final approval and permitting.

Solution

With sustainability concerns being top of mind, Evoqua’s disinfection team worked closely with the consulting engineer, KLH Engineers, to interface with PA DEP to get the final approvals. Evoqua provided two pre-validated SX-635-16 ETS-UV™ ultraviolet systems to meet the MTMA’s design and disinfection requirements. Along with reducing the system’s footprint requirements, MTMA experienced energy savings. MTMA was also able to reduce chlorine feed.