The first is to discharge to the sanitary sewer. If you use the sanitary sewer you will be assessed a sewer charge on your County water bill. This charge helps pay the costs of operating this system.
The second method is to discharge waste water to a septic system. Because these are privately owned systems the County does not levy a charge for their operation.
A simple way to check on which method you use for waste water disposal is to check your Gwinnett County Water Bill. If you are assessed a sewer use charge on your water bill then you are using the sanitary sewer system, if however your "Sewer Amount Charged" is $0.00, it is very likely that you are using a septic system. If you have a septic tank your bill should be similar to the example shown below.