1. Mobilization is a fixed cost getting spread across your work
Rolling a vactor truck, a support vehicle, and a two-person crew to a site is roughly the same expense whether we clean four basins or forty. On a small job, mobilization is 40% of the invoice. On a big job it's 8%. This is why bundling — cleaning every structure on the property in one visit — always beats piecemeal work. HOAs that split cleaning into "the front eight this quarter, the back six next quarter" pay a mobilization premium twice.
2. What's in the sump
A sump that's 20% full of dry silt takes eight minutes to clear. The same sump full of saturated mulch, standing water, and a decade of Publix bags takes 25. And what comes out matters at the tip: clean sand goes to a construction spoil site cheaply; anything with hydrocarbon contamination goes to a specialty facility at 4–6x the rate. We can't tell you which yours is until we open the lid — which is why the honest per-basin numbers are always a range, not a single figure.
3. Access
A curb inlet on an open drive lane is a five-minute setup. A grate under a parked-solid line of cars in a Miami Beach condo garage is an hour of coordinating tow notices, waiting for owners, and squeezing a hose through a tight turn. Traffic control on a state road (arrow board, MOT permit) is another line item entirely. Access explains more cost variance than debris volume does.
4. Structure depth and type
A shallow curb inlet is fast. A four-foot-deep manhole with a sediment shelf takes longer. A conflict structure with three incoming pipes at different elevations takes a confined-space setup and a longer vactor arm. On sites with a mix — most commercial properties — the per-structure number is a blended average, not a single rate.
5. Are you buying documentation, or just cleaning?
Compliance-driven work (SFWMD ERP, MS4 recordkeeping, post-DERM NOV) requires before/after photos of every structure, disposal manifests, a signed report, and often CCTV. That documentation package adds crew time and back-office hours. Straight cleaning with no paperwork is cheaper — but if you're one inspection away from a fine, the documentation is the actual product.
Ballpark ranges (South Florida commercial, 2026)
- Standard curb inlet, bundled cleaning: $100–$250
- Mid-size basin with grate, moderate debris: $200–$400
- Deep structure or manhole, documentation included: $300–$600
- Emergency single-structure callout with mobilization: $450–$900
Full breakdown on the storm drain cleaning cost guide, catch basin cost guide, and hydro jetting cost guide. Service pages: storm drain cleaning and catch basin cleaning.
