What the ordinance actually requires
The core rule is Sec. 16.24.060: grease interceptors "must be pumped out completely a minimum of once every 90 days, or more frequently as needed," to keep grease out of the sanitary sewer. Complete removal is spelled out: floating materials, wastewater, and bottom sludge and solids all leave the tank. The half-measure where a hauler pumps the trap, skims the grease, and decants the water back to save disposal volume? Explicitly prohibited.
Two more provisions catch operators off guard. Enzyme additives are banned outright; the ordinance says additives "shall in no way be considered as a substitution" for pumping. And the city expects records: a maintenance log with the date, amount pumped, hauler, and disposal site, plus monthly measurements of floating grease and settled solids in inches, submitted to the water utility by the 15th of the month after each quarter. If 90 days is genuinely more service than your flow needs, the ordinance has a variance process to extend the schedule (the fee starts at $50).
Equipment rules apply too: Wichita requires gravity interceptors with at least two compartments, and under-the-sink hydromechanical units "shall not be approved." Grease-producing facilities also hold a wastewater discharge permit. If you're fitting out a new kitchen, get the interceptor question answered before the plumber roughs it in.
What a grease trap pump-out visit looks like
- Full evacuation of the interceptor: grease cap, water, bottom solids
- A look at baffles and fittings while it's empty
- Manifest for your log: date, gallons, hauler, disposal site
- Disposal at a city-permitted facility. That part is the hauler's legal duty, but the log lives in your file
Schedule by the calendar, not the smell. By the time a trap announces itself to the dining room, you're past the ordinance and probably pushing grease into the lateral. That's how kitchens end up paying for jetting on top of pumping.
Lift stations
Lift stations sit at low points where gravity can't move wastewater onward, and they fail in a predictable way: the floats and cables that switch the pumps get tangled or coated in grease. The maintenance guidance from the Environmental Finance Center Network is to inspect and clean floats and cables at least quarterly and verify the high-level alarm actually trips. For restaurants and small commercial sites, the practical move is putting the lift station on the same quarterly visit as the grease trap: one truck roll, both boxes checked.
Home with a septic system instead? Grease is on the never-flush list there too. It just fails slower in a house than in a fry kitchen.
Sources for this page
- Wichita Code of Ordinances, Ch. 16.24 (90-day rule, complete removal, decanting ban, additive ban, logs, equipment, permits, variance)
- Environmental Finance Center Network: Lift Station O&M (float/cable failures, quarterly inspection)
- EPA: Septic Care (grease and residential systems)