Universal Site Services | Commercial Site Services
Rain in parking lot, postponing sweeping service by Universal Site Services.

Should I Sweep My Parking Lot When It Rains?

The rainy season can put a hitch in many of your regular activities. But does it also mean you have to stop sweeping your parking lot? Not necessarily. In fact, many people often make the mistake of canceling their regular sweeping services during rainy weather. But this will actually do more harm than good, not only for your parking lot, but for the environment as well.

At Universal Site Services, we recommend that our customers keep their regularly scheduled parking lot sweeping services during the rainy season. While some schedule shuffling will undoubtedly happen, it’s really best for you to continue sweeping your parking lot year-round. Here’s why.

What’s Going Down the Storm Drain?

To answer the question of whether or not you should continue sweeping your parking lot when it rains, we need to first consider a few questions. First, what exactly is it that goes down your storm drain? The answer: a whole lot. When you wash your car, change your oil, forget to pick up a chips bag that flew out of youParking lot sweeping advice during rain by Universal Site Services. r car, you’re adding potential pollutants to the storm drain. What might seem like a small amount can quickly add up when you multiply by hundreds of thousands of people who are doing the same thing, and a teaspoon of one toxic chemical easily turns into thousands of gallons going down the storm drain.

And where does this water go? Ultimately, it flows back into the ocean. But before that, it goes to whatever the nearest water body is. No matter where the water ends up and when, the sentiment is the same: we need to be careful and watch what is making its what from our streets, down our storm drains, and back into the public water system.


The streets are covered with garbage, whether you notice it or not. Empty candy wrappers, old soda cups, lids, napkins, half-eaten food scraps – all of this is present on our roadways. And, believe it or not, litter is also a huge problem in commercial parking lots. Because people don’t treat the parking lot like they would their cubicle or their own personal space, there’s a higher incidence of littering. We see it every day when we go to clean out our sweeping vehicles. Here are just a few of the things our sweepers pick up:

  • Cigarette butts
  • Food wrappers
  • Gum wrappers
  • Plastic bags
  • Soda cans
  • Lost clothing items (it’s true)
  • Drink carriers
  • Paper items
  • Food waste

The list goes on. And on.


There is also quite a bit of chemical waste in your parking lot, too. While we’re all well-aware that driving our cars isn’t great for the environment, now parking them can cause problems, too. For instance, as your car sits and cools off, it leaks vapors and condensation. Not only that, but have you ever pulled out from a parking spot and noticed a few drops of oil left behind by your vehicle? Well, guess what happens when it rains? That oil is washed away with the rainwater, and while your parking lot might be clean, our storm drains sure as hell aren’t. Oil, fuel, window washer fluid, and other chemicals from your vehicle all are flushed down the storm drain into the public water system.

How to Lessen Storm Drain Pollution

So what can you do about all of this mess? We know that parking lots are a breeding ground for litter and pollution, and that it has negative impacts on the environment as well as how people perceive your business. So how can we counteract those negative effects?

1.    Keep a regular sweeping schedule

2.    Provide plenty of trashcans

3.    Put up signs to discourage littering

4.    Install security cameras to deter vandalism

5.    Designate specific smoking areas


In sum, you should sweep your parking lot during the rainy season. Parking lot sweepers and vacuums will remove any litter and chemical debris from the pavement, meaning the rain won’t wash them down into our water system. You can work with your parking lot sweeper to reschedule services if it’s raining during your normal appointment time. But please, don’t just cancel your services altogether during the rainy season.

Parking lot sweeping is a great way to combat pollution and prevent our water supply from getting contaminated. Contact your local parking lot sweeper today to schedule services for your property. At Universal Site Services we offer professional and complete lot cleaning including parking lot sweeping in Vista, San Marcos, and the rest of the California.