Why Your Kitchen Drain Keeps Clogging (and How to Break the Cycle)

You have the dish pit drain cleared. Six weeks later, same story. If that sounds familiar, the problem isn’t bad luck — it’s that drain clearing treats the symptom, never the cause.

The clog cycle

Grease doesn’t block a drain overnight. It settles on the walls in layers, every service adding a film. The usable diameter shrinks month after month, until one day a trifle — a mop bucket, the bottom of a sauce pot — closes the passage.

The auger then punches a tunnel through the deposit. Water flows again, everyone breathes… but the walls stay coated. The thicker the deposit, the faster the tunnel closes. That’s why the intervals shrink: six weeks, then four, then two. You’re not paying for drain clearing — you’re subscribed to the same blockage.

Cause #1: the grease trap (or its absence)

In most kitchens stuck in the clog loop, the culprit is upstream: a saturated, undersized or bypassed grease trap sends grease straight into the lines.

• Saturated: past 25% grease and solids, the trap stops separating (the 25% rule explained).
• Undersized: too small for the dish pit’s real flow — it overflows at peak hours. Check with our grease trap calculator.
• Bypassed: a connection sending a greasy sink straight to the sewer, skipping the trap — common after a rushed renovation.

A properly sized, properly maintained grease trap breaks the cycle at the source.

Cause #2: the line itself

Sometimes grease is only half the story. A back-pitch (a belly where water stands), a shifted joint or a sagging section creates a low point where everything accumulates — grease, solids, grit. No amount of clearing fixes a slope.

These defects are invisible from the surface; only a camera inspection reveals them, with their exact position. It’s the step that turns “we’re clearing it again” into “we know exactly what to repair.”

Cause #3: kitchen habits

The drain receives what the kitchen sends it. A rushed crew can cancel out the best grease trap. The basics:

• Scrape plates and pans into the garbage before the dish pit — solids don’t belong in the drain.
• Never pour fryer oil down a sink: recovery container, period.
• Strainers and baskets in place on every floor drain and sink — and emptied at close, not when they overflow.
• Mop water goes in the floor drain (with its strainer), not the dish pit.
• Post the rules by the dish pit and include them in onboarding — staff turnover is the drain’s silent enemy.

Breaking the cycle: the sequence that works

1. Camera inspection — identify the real cause: uniform deposit (grease problem), low point (pipe problem), or both.
2. Full hydro-jetting — strip the deposit off the walls along the full run, not punch a tunnel. You restart with the full diameter. (Our approach to commercial drain cleaning.)
3. Fix at the source — pump out or resize the trap, correct the connection, repair the defective section, train the crew.
4. Planned maintenance — a maintenance contract with preventive jetting outside business hours, at a frequency based on your real history.

A drain that clogs “all the time” is a drain nobody has diagnosed yet. Request a quote — the first step is a diagnosis, not a package.