All bills for water, garbage collection and sewer services shall be rendered during the last week of each calendar month, and shall state the charge for the billing period during which the bill is rendered. The bills for each service may be consolidated on a single statement, so long as each service is separately identified and charged. Each statement shall plainly indicate that the bill becomes past due on the fifteenth day of the calendar month after which it was rendered. (Ord. 256 §3B, 1984)