About a week from today (Tues.), the city of Napoleon will commence construction on their downtown street project.   The work will begin on replacement of the waterline on Perry Street in the area of Riverview and Main Street.   The project is expected to take between 8 and 10 weeks to complete, and will include a new waterline, along with replacement of the street and sidewalks downtown.               Henry County Commissioners met with Napoleon officials to discuss the replacement of the sidewalks around the county courthouse as a portion of the downtown project.  A handicapped ramp will be added to at least one courthouse entrance during construction.  Deadline for completion of the street and sidewalk improvements in Napoleon is November 23rd.