Iowa Grease Trap Regulations
FOG Compliance Overview
Iowa follows the International Plumbing Code (IPC) as its base plumbing code. The IPC requires grease interceptors for food service establishments and references sizing based on fixture unit counts and flow rates. The state's regulatory authority is the Iowa Department of Natural Resources (DNR).
With approximately 6,644 food service establishments statewide, Iowa has significant FOG compliance needs. Individual cities and municipalities may adopt additional local ordinances that go beyond the state plumbing code, including stricter pumping schedules, permit requirements, and enforcement penalties. Of the 5 cities we cover, 3 require a dedicated FOG permit. 2 cities enforce the 25% rule for grease trap pumping.
Need a grease trap in Iowa?
Our free calculator uses IPC code requirements to recommend the right size for your establishment.
Size My Grease TrapCity Regulations in Iowa
| City | Pumping Frequency | Permit | 25% Rule |
|---|---|---|---|
| Clinton | Regular cleaning required; frequency determined by esta... | Required | — |
| Des Moines | See details | — | — |
| Dubuque | See details | Required | — |
| Sioux City | weekly; or when grease/solids reach 25% of capacity | — | Yes |
| Waterloo | Per maintenance schedule; 25% rule referenced in progra... | Required | Yes |
Frequently Asked Questions
What plumbing code does Iowa follow for grease traps?
Iowa follows the International Plumbing Code (IPC). The IPC requires grease interceptors for food service establishments and sizes them based on fixture unit counts and flow rates. Individual cities may adopt stricter local ordinances.
How many food service establishments are in Iowa?
Iowa has approximately 6,644 food service establishments according to Census Bureau County Business Patterns data. We currently cover detailed FOG regulations for 5 cities in the state.
Do I need a grease trap permit in Iowa?
Permit requirements vary by city. Of the 5 cities we cover in Iowa, 3 require a dedicated FOG permit. Check your specific city's requirements below or contact your local wastewater authority.
What size grease trap do I need in Iowa?
Grease trap sizing in Iowa depends on your establishment's flow rate, number of fixtures, and local code requirements under the IPC. Use our free sizing calculator for a recommendation tailored to your setup.
Regulations change frequently. Always verify current requirements with your local wastewater authority or plumbing inspector before making compliance decisions. Last updated: March 2026.