(Excerpted from the City of Fort Worth, Texas Water Guidance Document for sizing and installation of grease traps and interceptors - to see the whole document in PDF form, click here).

Commercial Laundries, Laundromats, and dry-cleaners shall be equipped with an interceptor in order to reduce the quantity of lint and silt that enter the collection system. The system must be of adequate size and design to allow for cool-down of wastewater so that separation can be more readily achieved. The interceptor must be installed with a wire basket or similar device, removable for cleaning, that prevents passage into the drainage system of solids 1⁄2 inch (12.7 mm) or larger in size, string, rags, buttons or other materials detrimental to the public sewerage system.

Sizing must be in accordance with guidance found in the Uniform Plumbing Code (UPC), Appendix H which uses the following formula:

(TGC) x (CPH) x (RT) x (ST) = Size of Lint Interceptor (gallons)
Where: TGC = Total Gallons per Cycle CPH = Cycles per hour
= Retention time 2.5 for Institutional Laundry 2.0 for Standard Commercial Laundry 1.5 Light Commercial Laundry
= Storage Factor, based on hours of operation; 1.0 for 8 hours of operation 1.5 for 12 or more hours
Currently, no effluent sample well is required for small commercial laundries. However, large and/or industrial laundries may be subject to Federal Pretreatment regulations. For more information please contact the Fort Worth Water Department, Pretreatment Services Division, at (817)871-8305.