It is hereby approved, adopted and established that the strength charge established by section 7-5-15-2 of this chapter shall be paid by each industrial user receiving waste treatment services and subject thereto before the twentieth day next succeeding the date of billing thereof to such user by or on behalf of the city, and such payment thereof shall be deemed to be delinquent if not so paid to the billing entity before such date. Furthermore, it is hereby established, approved and adopted that if such payment is not paid before such date, an industrial user shall pay interest compounded monthly at the rate of two-thirds of one percent (2/3%) per month on the unpaid balance due. (Ord. 105, sec. 4, 2-7-1977)