In Miami-Dade, the safe rule is simple: only rain belongs in a storm drain. Water that carries detergent, bleach, oil, paint chips or heavy sediment should be kept out of street inlets, canals and retention areas, and collected or directed onto soil where it can soak in. The county does not appear to have a rule written for pressure washing by name, but general bans on non-stormwater discharges apply to wash water like any other pollutant.
Why the local geography raises the stakes
South Florida sits on porous limestone with a shallow water table. The Biscayne Aquifer, designated a sole source aquifer by the U.S. Environmental Protection Agency in 1979, supplies most of Miami-Dade's drinking water, and Miami-Dade's water department reports that its wells draw mainly from it. Whatever soaks into the ground can reach groundwater quickly.
The surface water system is just as sensitive. Street inlets feed an extensive canal network, and many of those canals empty into Biscayne Bay. Storm drains do not lead to a treatment plant. Depending on the neighborhood, an inlet connects to a canal, a lake or underground trenches and wells that return water to the ground, so it is effectively a direct connection to the water around us.
What the rules say, in plain terms
- No non-stormwater discharges. City and county stormwater regulations in Miami-Dade prohibit discharging anything other than stormwater into the drainage system. Municipal programs, such as Hialeah's, state this expressly.
- The county enforces water-quality rules. The county's environmental regulator, commonly called DERM and part of the Department of Regulatory and Economic Resources, investigates issues such as turbid discharges into waterways, canals and Biscayne Bay. The county's environmental complaints page explains how concerns are routed, and 311 is the general entry point.
- Cities have their own programs. The county has more than 30 municipalities, and many run their own stormwater education and code enforcement. Check your city's public works or code compliance page.
- Water restrictions are different. The county's year-round water restrictions govern landscape irrigation and apply to any water source. The county's page lists pressure cleaning of paved surfaces among the exempt activities, which means watering-day limits do not stop you from cleaning a driveway. It does not mean the wash water can go anywhere.
These are summaries for general information. For a specific project, particularly a commercial one, confirm requirements with your city and the county.
What counts as a problem discharge
| Situation | Concern | Better practice |
|---|---|---|
| Soapy water running down a driveway into a street inlet | Detergents reach canals | Direct runoff to lawn, or collect and dispose of properly |
| Bleach solution left to run off a roof or wall | Harms plants, aquatic life | Dilute, wet plants first, limit volume, and rinse onto soil |
| Greasy water from a dumpster pad into a drain | Oil and grease in storm and sewer systems | Hot-water wash with wastewater recovery; see the FOG rules |
| Muddy water or paint chips from stripping | Sediment and heavy metals | Containment berm, vacuum, filter |
| Wash water draining across a neighbor's property | Nuisance and liability | Redirect to your own landscape |
Practical steps for a cleaner job
- Dry clean first. Sweeping and bagging debris cuts the amount of material in the wash water. West Miami's municipal stormwater guidance, for example, advises dry sweeping instead of hosing down driveways.
- Use less water. A rotary surface cleaner and a properly sized nozzle give a good result with less runoff than a bare wand.
- Choose cleaners carefully. West Miami's guidance advises avoiding cleaners with hazardous ingredients such as bleach where possible, and that wastewater with high pollutant levels should be collected, not left to evaporate.
- Block the drain. Drain covers, inlet mats and berms keep wash water out of the system during the job.
- Recover and filter. For commercial sites, wet vacuums or reclaim mats collect water so it can be filtered and disposed of correctly.
- Know your disposal options. Plain rinse water onto landscaping is a different matter than chemically treated water. Do not pour contaminated water down a storm drain, and check with your utility before discharging to the sanitary sewer.
Restaurants, garages and other special cases
Properties with grease interceptors or oil-water separators have additional obligations. Miami-Dade's Fats, Oils and Grease training materials say that wash water from cleaning mats and equipment cannot reach the ground, groundwater, surface waters or storm sewers, and must go to the grease interceptor. The commercial guide explains how that fits into recurring service. Marinas and waterfront property raise their own issues, since runoff reaches water almost immediately.
What homeowners should expect from a hired crew
A responsible provider should be able to explain, without being pressed, where wash water will go and which products they use. It is worth asking whether they use drain covers, how they handle chemical-laden water, and whether their practices differ near a canal or lake. The checklist in choosing a pressure washing company includes those questions. If you are doing the job yourself, the do-it-yourself guide has a section on setting up.
If you see a problem
Cloudy, soapy or oily discharges entering a storm drain, canal or the bay can be reported through 311. Note the location, time and what you saw, and take photographs from a safe distance. Do not confront anyone.
Frequently Asked Questions
Can I wash my driveway if it drains to the street?
Plain water and a small amount of mild cleaner are less of a concern than heavy detergent, bleach or oil. Keep the water on your property if you can, and avoid letting soapy or contaminated water reach the inlet.
Does the water restriction ban pressure washing?
No. Miami-Dade's water restriction page lists pressure cleaning of paved surfaces as exempt. The rules target landscape irrigation.
Is bleach allowed in wash water?
It is commonly used, but it must not be discharged to storm drains or allowed to flow into canals. Dilute, protect plants and collect runoff where feasible.
Who enforces runoff rules?
The county, through DERM, and cities through their own stormwater or code enforcement programs. Which one applies depends on where the property is.
What should a contractor do with the wash water?
Block drains, minimize volume, collect or filter contaminated water, and dispose of it properly. Ask for their wastewater plan before hiring.