A wash bay is concrete plus environmental engineering. The slab has to handle wheel loaders and dump trucks while sloping to trench drains that route to oil-water separators before the water hits the storm system. Detroit Concrete pours wash bays with the right slab thickness, drainage geometry, and chemical-resistant surface for heavy equipment operations. Every project starts with a free written estimate.
A wash bay is the one place on your property where hydrocarbons, sediment, and detergents concentrate into wash water that has to leave the property without ending up in the storm system. Storm-water regulations require that wash water route through an oil-water separator before discharge; the concrete has to be engineered to deliver wash water to the separator without spilling around it.
We engineer the slab thickness for the heaviest equipment that will use the bay, slope every direction to trench drains positioned for efficient capture, integrate the oil-water separator with the drain system, and use chemical-resistant surface treatments where degreasers or harsh detergents are part of the wash cycle.
Wash bay dimensions, slab thickness for the heaviest equipment, slope to trench drains, oil-water separator capacity, and the discharge connection are all engineered as one integrated system.
Excavate bay to subgrade
The bay footprint is excavated to subgrade, compacted to engineered density, gravel base placed at the right depth, and any plumbing for trench drains and separator routed before forms go up.
Form, slope, pour
Forms are set with the engineered slope in every direction toward the trench drains, reinforcement placed for the equipment loads, and the slab poured and finished for the wash environment, broom-textured for foot grip during wash operations.
Install separator and test
Trench drain grates are installed, the oil-water separator is connected to the discharge, the system is tested with water to confirm slopes carry water to drains and the separator processes properly before being handed off.
Why wash bays fail
Slope Is What Makes a Wash Bay Work
A wash bay that does not slope properly is just a concrete pad that holds water until it evaporates. Every direction across the bay needs slope toward a drain, and slope has to be consistent so water does not pool in corners or low spots. We verify slope during the pour, not after; getting it wrong means tear-out because slope cannot be added to cured concrete.
Coordinate with the rest of heavy equipment services on the property and with environmental compliance for the separator and discharge details. The wash bay is one piece of the larger environmental story across our industrial concrete work.
Trench drains, oil-water separators, slope verification and storm-water compliance.
Storm-water regulations require hydrocarbons to be removed before wash water enters the storm system. Oil-water separators are the engineered solution; without them, the wash bay's discharge violates discharge limits and can trigger fines or shutdowns.
During the pour with a level and a water flow test, then again after cure. Every direction across the bay must carry water to a trench drain; pooling anywhere means the slope is wrong and needs correction before the slab cures.
Sometimes, if it can be sloped (often it cannot), drained (usually needs new trenches cut), and routed to a separator (almost always new work). The economics often favor a purpose-built bay; we will assess case-by-case.
Yes if degreasers or harsh detergents are part of the wash cycle. Standard concrete surface degrades under repeated alkaline or solvent exposure; chemical-resistant treatment extends slab life dramatically.
Several weeks from excavation through cure and separator install. The full schedule is in the quote, including time for the environmental discharge connection if regulatory review is required.
New wash bay with proper slope to trench drains and the oil-water separator we needed for compliance. Discharge passes regulatory inspection, equipment gets washed faster, no more puddles in corners.
Z. K5
Fleet Manager, Detroit
★★★★★
They engineered for our wheel loaders and dump trucks, the heaviest stuff we run. Slab has held under daily traffic, drainage works through every wash. Right tool for the actual fleet.
Y. K5
Operations Director, Warren
★★★★★
Wash bay with chemical-resistant surface for the degreaser we use. Three years of operation, no surface degradation, separator processes hydrocarbon properly. Compliance side covered.
Q. K5
Mining Operations, Ann Arbor
★★★★★
They tested the slope with water before signing off. Pooled in one corner; they corrected it before cure. Final result drains perfectly. Real install discipline.
X. K5
Construction Yard Manager, Sterling Heights
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