Due to the recent transition to the City's new water meter reading system, a delay in meter installations resulted in water meter readings being taken out of the customary 2 month cycle and therefore the billing statement you received in October (06/11/13-08/10/13) actually covered 3 months of water usage.
To offset the issue, the most recent bill for November (08/11/13-10/10/13) covers only 1 month of usage. The subsequent bills will revert back to the customary 2 months of usage.
If you have additional questions please contact City Hall at 847.432.1924.