The Soquel Creek Water District board members on Tuesday said they were convinced the planned Pure Water Soquel plant should be split into two sites — partly in the city of Santa Cruz and partly in Live Oak. When approving the Pure Water Soquel project in December, board members prioritized building a final-stage purification plant at a lot at the corner of Chanticleer Avenue and Soquel Drive and an initial “tertiary” treatment facility at the city of Santa Cruz’s Wastewater Treatment Facility on California Street. At the same time, the board told district staff to undertake a parallel investigation of building a two-story full purification and tertiary treatment plant at the wastewater facility — so long as the effort did not delay the overall project.