What must a type 3 marine sanitation device have when boating on inland waters?

A Type III marine sanitation device (MSD) must have a holding tank that stores sewage and waste without discharging it into the water. This type of MSD is designed for use in inland waters where overboard discharge is prohibited. Additionally, it should be equipped with a means to indicate when the tank is full, ensuring that waste is properly managed and disposed of at designated facilities.