Is It Illegal to Dump Sewage Into My Storm Drain?
Last updated October 31, 2026
The short answer
Why It Is Illegal
Storm drains are part of a separate system from sanitary sewers. They collect rainwater and snowmelt and direct it to rivers, lakes, or the ocean without treatment. Sewage contains pathogens, chemicals, and organic matter that can contaminate drinking water sources and harm aquatic life. Clean Water Act regulations and local ordinances make it a violation to discharge pollutants into these systems.
In this city, municipal code and state environmental laws mirror these federal standards. Property owners can face civil penalties, cleanup costs, and even criminal charges for willful dumping. The law treats sewage as a hazardous pollutant, so the consequences are serious. Even accidental sewage overflow into a storm drain can trigger reporting requirements and liability.
What Counts as Sewage
Sewage includes wastewater from toilets, sinks, showers, washing machines, and floor drains. It also covers water from sewage backups, septic system overflows, and portable toilet waste. Anything that contains human waste, gray water, or contaminated runoff from a sewage spill is considered sewage. Dumping any of this into a storm drain is illegal.
Some homeowners mistakenly believe that diluted sewage or gray water is harmless. That is not true. Even small amounts can contain harmful bacteria like E. Coli and viruses. The law does not distinguish between raw sewage and diluted wastewater. Both are prohibited from entering storm drains.
- Toilet and urinal waste
- Wastewater from sinks, tubs, and showers
- Washing machine and dishwasher discharge
- Water from sewage backup cleanup
- Septic tank or cesspool overflow
- Any water contaminated with fecal matter
If You Already Dumped Sewage
If you accidentally dumped sewage into a storm drain, stop immediately and contact your local public works or environmental agency. Many municipalities require you to report the spill. They can advise on cleanup and notification steps. Do not attempt to flush the drain with large amounts of water, as that can spread contamination further.
For sewage that has already entered the drain, the damage is done. Your focus should be on preventing further releases and cleaning the area around the drain. If the spill occurred on your property, you may need professional help to sanitize the affected surfaces. Local water damage pros can handle this type of cleanup safely.
How to Dispose of Sewage Properly
The only legal way to dispose of sewage is through the sanitary sewer system, either via your home plumbing or a septic hauler with proper permits. If you have a sewage backup, the water should be pumped and contained, then disposed of through a permitted process. Never pour it into storm drains, yards, or street gutters.
For small amounts, such as from a portable toilet, use a designated dump station or a waste transporter that follows local rules. Your local wastewater treatment plant can provide guidance on proper disposal. If you are unsure, call your city's public works department. They can tell you the legal options in your area.
- Sanitary sewer cleanout or toilet
- Septic system (if designed for it)
- Septic or portable toilet service that follows local rules
- Designated RV or portable toilet dump station
- Hazardous waste facility for chemical contaminants
When Sewage Backup Happens
Sewage backups often occur during heavy rain or when the sanitary sewer is overwhelmed. If sewage backs up into your home, do not let it flow into storm drains. Close any floor drains that connect to storm sewers and contain the water as well as you can. Then call a professional for cleanup and sanitation.
Professional sewage cleanup involves removing contaminated water, sanitizing surfaces, and disposing of waste properly. The pros use protective equipment and follow local regulations for disposal. They can also help with structural drying and dehumidification to prevent mold. Prompt action reduces health risks and property damage.
If you live in this city, note your shutoff valve location and know where your storm drain connections are. That helps you act quickly during an emergency. After any backup, document the incident and contact your insurance company to discuss coverage. Policies vary, and your insurer decides what is covered.
Need help right now?
Phones are answered 24/7 for Quincy and nearby communities.
Call Now (617) 404-2753Frequently asked questions
What happens if I get caught dumping sewage?
Penalties can include fines, cleanup cost recovery, and legal action. Local and federal agencies may inspect your property. In serious cases, criminal charges are possible. The exact consequences depend on the amount and intent.
Can I flush sewage down a toilet instead?
Yes, flushing sewage down a toilet is legal because it enters the sanitary sewer system. However, do not flush large amounts of solid waste or chemicals that could harm the sewer. For large volumes, use a septic hauler that follows local rules.
Is it illegal to dump gray water in a storm drain?
Yes, gray water from sinks, showers, and laundry is also considered sewage. It can contain bacteria and chemicals that harm waterways. Disposal must go through the sanitary sewer or a permitted septic system.