Illegal Discharge of Pollutants

An illegal or illicit discharge refers to any unauthorized or illegal release of pollutants — whether intentional or unintentional — into a stormwater drainage system or body of water.

Stormwater systems are designed to carry only rainwater. When other substances like motor oil, chemicals, sediment, trash, sanitary sewage, paint, or even soapy water enter these systems, it’s considered an illegal discharge. These pollutants typically flow directly into local rivers, ponds, marshes, or oceans without treatment, harming water quality, aquatic life, and public health.

Illegal discharges can be:

• Unintentional like leaking vehicle fluids (gas, oil, hydraulic lines), over-irrigation of yards (pesticides and fertilizers), or broken septic systems.
• Intentional such as dumping paint, grease, or blowing yard waste (leaves, pine straw, or grass clippings) into a storm drain, construction site sediment entering a water body, and chlorinated or saltwater pool discharges into the drainage system.

Examples include:

• Pouring chemicals, paint, grease or oil into a storm drain
• Pet waste on the ground draining into nearby storm drain or water body
• Leaking dumpster fluids flowing into the street or nearby storm drain
• Washing dirty cars with soap where the runoff goes to a storm drain
• Sewage from failing septic tanks or overflowing lift stations entering ditches or pipes

Concerns about illegal discharges

In coastal areas, stormwater systems often drain directly into sensitive waterways like marshes, rivers, creeks, and the ocean — without treatment. When pollutants from illegal discharges enter these systems, they contaminate water that's vital for ecosystems, recreation, and even drinking water in some areas.

Coastal environments host diverse ecosystems including fish, shellfish, birds, and aquatic plants. Illegal discharges, such as chemicals, oils, sewage, or debris, can:

• Reduce oxygen levels (leading to fish kills).
• Disrupt breeding and feeding grounds.
• Introduce toxins into the food chain.

Contaminated coastal waters can pose health hazards to swimmers, boaters, and fishermen. Bacteria from illegal discharges (like raw sewage) can lead to beach closures and shellfish bed advisories, threatening both recreation and livelihoods.

Some illegal discharges (like dumping grease or yard debris) can clog stormwater infrastructure, reducing flow capacity and increasing the risk of flooding during storms or high tides.

In a coastal community, protecting water quality is not just an environmental issue. It's about preserving ecosystems, protecting public health, and sustaining the local economy. That's why preventing and reporting illegal discharges is critically important.

What you can do to prevent pollution

Never release, dump, or pour anything into a stormwater drainage system other than rainwater!

Be the solution to stormwater pollution! Remember, only rain down the drain!

Reporting suspected illegal discharges or dumping in water ways helps protect the environment and keeps local water ways clean.

Report illegal or illicit discharge

If you observe an illegal or illicit discharge, connection, dumping, or pollution, flooding, construction site runoff, or other stormwater-related issues, please report it in one of the following ways:

• Call the Town's Stormwater Hotline at 1-843-671-RAIN (7246)
• Contact the Stormwater Utility via email at stormwater@hiltonheadislandsc.gov.
• Submit a ticket using our MyHHI mobile app.

Report a Concern

Common pollutants discharged in residential areas:

• Pet waste
• Yard Debris (leaves, grass clippings, pine straw, mulch)
• Fertilizer
• Pesticides
• Herbicides
• Broken septic systems, drain field leachate
• Over irrigating lawns
• Vehicle maintenance (fluids, oils, grease)
• Car washing
• Pool discharges
• Fats, Oils, Grease (FOGs) down storm drains

Common pollutants discharged in commercial areas:

• Fats, Oils, Grease (FOGs) down storm drains
• Grease traps overflowing, grease poured on the ground
• Paint
• Drywall
• Concrete
• Asphalt activities
• Fuel
• Dumpster juice
• Landscaping debris
• Construction activities (sediment)
• Pool maintenance
• Maintenance facilities/activities
• Hydraulic line failures