The ceremony at The Garden of Reflection 9-11 Memorial will begin at 8:30 a.m. with the tolling of a bell nine times to remember the 9 victims from Lower Makefield.
Starting Wednesday Pennsylvania American Water will be using a form of chlorine called "free chlorine," a stronger disinfectant which is often used to flush water mains and fire hydrants in its Yardley District.
Police were outside a home on Heritage Oak Drive in Lower Makefield performing a welfare check around 6:10 p.m. when they noticed two bodies inside lying on the floor.