Frequently Asked Questions

​​Commercial Inspection

​​1. Does my service business need a pretreatment device?

Grease, oil, or sand interceptors are required for laundries, restaurants, service stations, auto repair shops, carwashes and other facilities. For example, pretreatment devices are necessary for the proper handling of liquid wastes containing grease or oil in excessive amounts or any flammable wastes, sand, and other harmful ingredients. Such interceptors are not required for private living quarters or dwelling units.

2. How do I know my grease, oil, or sand interceptor is adequately sized?

Specific requirements are identified on our Grease Interceptor Sizing Calc​​ulations page

3. What are 'one-time' temporary discharge permits, and how do I get one?

One-time temporary discharge permits may be issued for the disposal of contaminated groundwater and other one-time discharges into the city of Phoenix sanitary sewer system. Requests for one-time temporary discharge permits must be in writing and mailed to the Commercial Program Supervisor two weeks prior to the anticipated discharge date(s).

John Cummings, Chief Water Quality Inspector - (602) 495-7412

Mailing Address:
City of Phoenix Environmental Services Division
Commercial Inspection Program
2474 South 22nd Avenue, Building 31
Phoenix, Arizona 85009