Hydrocarbons Stormwater Pollution

Hydrocarbon Pollution

Spot It – Report It – Stop It!

Jump To:

Hydrocarbons Overview Types of Hydrocarbons What You Can Do To Help Prevent Stormwater Pollution

Hydrocarbons Overview

There are thousands of hydrocarbon compounds (a compound of hydrogen and carbon) that exist in the world, some of which are naturally occurring, and many man-made. They are a common pollutant found in stormwater that is transported to our rivers, lakes and streams, and come from many sources. Examples can include coal, insulating oils, tar, gasoline or diesel fuel, hydraulic fluids, motor oils, lubricants, fats, oils, and grease, or come from the result of burning wood, garbage, and other products. Hydrocarbons can be very toxic at low levels and can result in cancer and birth defects.

In many cases, a rainbow-like sheen and strong odor is common with hydrocarbon pollution and can be observed floating on our water bodies or seen on our surface streets and in our storm system after a discharge occurs.

If you observe stormwater pollution, call the Stormwater Helpline at 919-996-3940 or send an email to IllegalDischarge@raleighnc.gov. In instances where large spills occur from storage tanks or vessels, call the 911 emergency number.

Visual of iron bacteria and gasoline in a stream.

Please note: Oil typically bonds to itself and does not mix easily with water. In some instances, a bacteria sheen will look like oil. A simple test to tell the difference is to break the sheen by disturbing the material: Bacteria (to the left) will typically break into little platelets while oil (to the right) will reform to itself.

Types of Hydrocarbons

Petroleum spilling from a truck

Petroleum Hydrocarbons

The most common hydrocarbon pollutant found in stormwater is petroleum based. These chemical compounds are commonly the result of accidental releases of oil or fuel from vehicles and machinery. Thousands of small fuel spills can accumulate to very high concentrations as they are collected and transported by stormwater to a receiving water. The best way to prevent this from happening is to implement preventative measures at the source before it happens. If you notice a drip or leak, fix it!  If you see a small spill, clean it up!

Polycyclic Aromatic Hydrocarbons Stormwater Pollution

Polycyclic Aromatic Hydrocarbons

Polycyclic Aromatic Hydrocarbons, or PAHs, are a form of hydrocarbons that occur during an incomplete combustion of a hydrocarbon. They are often found in substances such as coal-tar, a common ingredient in pavement sealant. Additionally, they can be found in industrial processes such as power generation, vehicle emissions, and various manufacturing activities.

PAHs are toxic and have been associated with a range of adverse effects, including causing cancer or mutation of genetic material. They are also known to accumulate in aquatic life, leading to potential impacts on aquatic ecosystems.

What You Can Do To Help Prevent Stormwater Pollution

  • Inspect and maintain your equipment and vehicles regularly.  If you notice a drip or leak, fix it!
  • Have spill response material and procedures in place where fueling or maintenance occurs.  This can include adsorbent material, Booms, brooms and brushes, and disposal bags.
  • Regularly inspect your storage tanks for leaks.
  • Use non-PAH sealants for your pavement.
  • Regularly maintain your oil-water separators, grease trap interceptors, and other waste control measures before they fail.
  • Store your chemicals properly under cover and on pallets.



Zachary Poole
Illegal Discharge Coordinator

Engineering Services
Service Categories:
Related Services:
Spot, Report, and Stop Water Pollution