Sewer Charges

Fairfax Water does not maintain the sewer system, but we do provide a sewer billing and collection service for the County of Fairfax. This allows most Fairfax County residents to pay for both water and sewer services on a combined statement.

Residential customers are billed for use of the sanitary sewer system at a rate of $4.10 per 1,000 gallons. Sewer usage is based on water consumption during the current billing period or the preceding winter quarter billing period, whichever is lower. This prevents residential customers from being charged sewer rates on water used outdoors during the summer.

Commercial customers are billed for sewer use based on their actual water consumption. Some commercial customers use meters to separately measure water that does not drain to the sanitary sewer system, such as water used for irrigation or cooling systems. These metering arrangements do not benefit residential customers, whose winter quarter water consumption limits the amount of sewer usage billed in the summer months.

Another billing arrangement exists for customers who use the County’s sanitary sewer system and obtain their water from a well. These customers receive bills based on the average winter quarter water consumption for homes in Fairfax County. The average may be adjusted for each of these customers based on the number of residents in their home. This occupancy information is reported each spring on a form that is mailed with the sewer bill and returned in the payment envelope.