WATERVILLE — Efforts are underway by the developer of the Hathaway Creative Center and Colby College that could lead to more people living and working downtown, helping to spur economic development while enlivening the heart of the city. Paul Boghossian, the Hathaway developer, is working toward getting financing to develop two former more mill buildings in his Hathaway Creative Center complex off the north side of Water Street, while Colby College is looking at creating living spaces for students and faculty downtown. “There’s stuff percolating in Waterville that I think will raise the tide for everybody,” Boghossian said. Colby College is in the “exploratory phase” of its downtown plans, according to Colby spokeswoman Ruth Jackson.