Grease Trap Requirements
Bismarck, ND
FOG compliance regulations for food service establishments in Bismarck, North Dakota.
FOG Compliance in Bismarck, ND
Food service establishments in Bismarck operate under a combination of federal EPA pretreatment standards, North Dakota state plumbing code, and city-level FOG ordinances. Together these rules determine how grease traps must be sized, how often they must be pumped, and what happens when a restaurant falls out of compliance.
Pumping frequency is the compliance rule restaurant owners interact with most often. In Bismarck, the rule is: Twice per month or when 25% full. This aligns with the 90-day US median enforced by most major cities. The city follows the Uniform Plumbing Code (UPC) for trap sizing and installation. Under Section 1014, which applies a fixture drainage load formula with a retention time factor, grease interceptors installed in Bismarck must meet minimum capacity thresholds based on the fixtures connected to them — 3-compartment sinks, dishwashers, pre-rinse stations, wok stoves, and floor drains on the cook line.
Bismarck requires a dedicated FOG permit for any food service establishment generating fats, oils, and grease. The permit is separate from, and in addition to, the plumbing permit required at installation.
Bismarck enforces the 25 percent rule: grease traps must be pumped before the combined FOG and settled solids reach 25 percent of the trap's total liquid depth. Inspectors measure the depth with a sludge judge or dipstick, typically at surprise visits. Exceeding the threshold at inspection triggers a notice of violation and mandatory emergency pump-out, regardless of the scheduled pumping cycle. Establishments must maintain pumping logs, hauler manifests, and inspection reports on-site — missing records is itself a violation in most enforcement actions. Enforcement authority rests with the City of Bismarck Industrial Pretreatment Program / Public Works, which handles permit issuance, inspections, and hauler licensing.
For a deeper explanation of the rules this city enforces, read our guides on how grease traps work and the 25/50 pumping rule.
Pumping Requirements
Permits & Enforcement
Complete FOG Regulations
| Pumping Frequency | Twice per month or when 25% full |
|---|---|
| 25% Rule | Yes — trap must be pumped when grease and solids reach 25% of capacity |
| Permit Required | Yes |
| Record Keeping | Required — maintain pumping logs and manifests on-site |
| Plumbing Code | Uniform Plumbing Code (UPC) |
| Ordinance Ref. | FOG Control Ordinance Chapter 11.1-04; Industrial Pretreatment Ordinance Title 11.2 (updated 2025) |
| Authority | City of Bismarck Industrial Pretreatment Program / Public Works |
Additional Notes
NOTE: Bismarck is actually the capital of North Dakota (ND), not South Dakota (SD). Grease traps must be cleaned twice a month or when 25% full (updated from previous requirement of weekly or 50% full). Industrial Pretreatment Ordinance updated February 2025 to align with EPA Clean Water Act requirements. Fee thresholds moved to city's fees and charges schedule. Contact: Paul Olson, Industrial Pretreatment Manager, 701-355-1700 ext. 4.
Last verified: — Regulations change frequently. Always verify current requirements with your local wastewater authority or plumbing inspector before making compliance decisions.
Contact Information
(701) 355-1700 or bgefroh@bismarcknd.gov
Official Sources
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