History of the toilet

So who invented the toilet? Well…it wasn't Thomas Crapper, a famed Victorian plumber. It was, in fact, Sir John Harrington, a godson of Queen Elizabeth I, in the 1590's. Harrington's "privie in perfection" was a noisy, valved contrivance called Ajax. However, all wasn't coming up roses. At the time of this great invention, there wasn't a sewer to which it could be connected so it simply drained into a cesspool below and the stench outweighed its usefulness. It wasn't until some 300 years later that his invention got connected to a working sewer system. For a fun history of the toilet you can check out this article on www.oldhouseonline.com.

Automotive Repair Facilities (Garages and Service Stations)

(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).

Where automobiles are serviced, greased, or repaired or where gasoline is dispensed, oil/water separators shall have a minimum capacity of 500 gallons for the first 1000 square feet of area to be drained, plus 250 gallons for each additional 1000 square feet of area to be drained into the separator.

An effluent sampling well is required, per specifications listed in Part 1, Section F, Subsection d.
Note: Parking garages in which servicing, repairing, or washing is not conducted, and in which gasoline is not dispensed, shall not require a separator. Areas of commercial garages utilized only for storage of automobiles are not required to be drained through a separator.
Figure 1, Typical plumbing layout
Figure 2, Typical Grease Interceptor Schematic
Figure 3, Typical Sampling Well, Courtesy Park Env. Equipment Co.
Figure 4: Typical Grease Trap / Sample Well Installation, Courtesy Park Env. Equipment Co.


Car Washes

(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).

Where automobiles are washed (including detail shops utilizing hand-wash practices), separators shall have a minimum capacity of 1000 gallons for the first bay, with an additional 500 gallons of capacity for every other bay.

Additionally, wash racks must be constructed to eliminate or minimize the impact of run- off from rain/storm events. Minimum requirements are roofed structures with at least two walls and appropriate grading to prevent stormwater infiltration into the sanitary sewer.
An effluent sampling well is required, per specifications listed in Part 1, Section F, Subsection d.

Laundries

(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
RT
ST
= 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.

Other types of Interceptors and sizing requirements

(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).

Interceptors are required for oil, grease, sand and other substances harmful or hazardous to the building drainage system, the public sewer or sewage treatment plant. Design, size, and location of pretreatment devices must be submitted by a licensed plumbing contractor or professional engineer for review and approval.