In a commercial laundry does the sewers need to be separated before they go to the street i.e. 2 sewer connections

I've done Laundromats. If you're talking about a row of washers on one side with a common main and another on the other the two can be combined to exit the building and connect to the citty main. If I've misunderstood your question please post back. Regards, Tom

In my area, each property can have only One sewer connection. Therefore, as Tom said: combine those two in one sewer leading out of your property...