For wastewater treatment beyond that included in the base rate, customers will be charged an additional variable surcharge per hundred cubic feet (HCF). View current variable surcharge rates: https://www.sd1.org/DocumentCenter/View/74/SD1-Rates-and-Fees-PDF
Water usage is determined by a "winter factor," which considers only average winter water usage. This ensures that SD1 does not charge customers for the treatment of water used for outdoor activities. Once your winter factor (e.g. 5 HCF) is established each May, you are billed for that amount of wastewater treatment all year.