After a 4-year process, the City Council finally approved a comprehensive master plan for downtown Austin. The plan subdivides downtown -- defined as the area between the lake and MLK, I-35 and Lamar -- into 9 distinct areas with differentiated development and preservation plans. The plan will guide downtown development for the next 10 years.The 200-page plan will cost an estimated $350 million to carry out, money that will need to be raised through bonds, fees, or partnerships with private developers. Now, City staffers will turn the plan into detailed land use rules which will also require Council . . .