In many Canadian cities, you are required to have a grease trap alongside your dishwasher. For example, according to the City of Toronto, ‘it is mandatory for establishments that cook, heat, process or prepare food on-site to install, operate and maintain a grease trap (interceptor) on any pipe that connects directly or indirectly to a sanitary sewer system.’ Be sure to check your city’s regulations to determine if you need to connect a grease trap to your dishwasher.