Residential customers are billed for sewer based on the amount of water used in the winter months. In this way, you do not pay sewer charges on water you use outdoors for washing the car or watering the grass. Every residential customer will pay a sanitary sewer base fee of $50 which includes up to 8,000 gallons of water usage. Any usage over the 8,000 gallons will be charged at a fee of $5.70/1,000 gallons. Commercial customers are billed based on their water usage year-round.