Pretreatment Program

​Frequently Asked Questions

Pretreatment Program

Liquid Waste

What is a grease trap/grease interceptor?

A grease trap (or interceptor) is a plumbing device designed to physically separate grease and solids from kitchen wastewater.

What is the difference between a grease trap and a grease interceptor?

Grease traps and grease interceptors are both plumbing devices for grease removal from industrial wastewater discharge streams. The grease trap is generally thought of as the smaller indoor device, usually less than 100 gallons of liquid holding capacity, and, until recently, typically installed below a sink. Grease traps are usually made of steel and often designed with just a single compartment. The grease interceptor is generally considered the large pre-cast concrete tank, typically with a liquid holding capacity anywhere from 250 to 5,000 gallons and designed with two separate compartments. For the purposes of this website, the term "grease trap" is used to describe both devices.

In Dallas, a grease trap is required for any commercial or institutional food service operation.

What size grease trap will I need?

The size of the grease trap will be determined according to Dallas Plumbing Code  sizing criteria for grease traps. For more information contact Plumbing and Mechanical Section .

How often must my grease trap be cleaned?

The Dallas City Code, Chapter 19, Sec 19-126.2 (c) specifies all grease traps must be completely emptied and cleaned by a licensed hauler. The interceptors must be cleaned as often as necessary but not less than every 90 days, or whenever 25% or more of the interceptor contains floating materials, sediment, oils, or grease.

How do I dispose of grease trap waste?

Grease trap waste must be transported by a liquid waste hauler licensed by the Texas Commission on Environmental Quality and Dallas Water Utilities to a properly permitted disposal site