Homeowners could see a 4.6 percent increase in water/sewer bills for fiscal 2013, which starts July 1. The Board of Aldermen on Monday will continue a public hearing on a proposed new rate structure. Water rates would increase by 40 cents to $5.65, while sewer rates would increase by 25 cents, to $9.60. The rates are charged for every 100 cubic feet of usage. The average bill would increase to $971.72, from this year’s average of $929.22. The hearing is scheduled for 8 p.m. in the aldermen’s chamber at City Hall.