Sewage Spills
Check with your local health department
This webpage is not a source of health information. Please check with your local health agency to see if there are any public health notices, swimming area closures, or other restrictions in your area.
Also, please check the Department of Health Shellfish Safety Map or Commercial Shellfish Map for shellfish harvesting information or call their Health information line 800-525-0127.
In 2025, the Washington State Legislature passed the Sewage Spill Public Notice law (RCW 90.48.632 and 90.48.636). This requires Ecology to use this webpage to share sewage spill information reported to us by permitted wastewater treatment facilities. That means, we do not include information such as sewage backups from private homes and businesses, illegal dumping, or other spills reported to Ecology. After we receive the report from the facility, our goal is to publish the information within five working days. Also, after the spill has concluded, we update the table with any final information that has been reported and include a link to the official report (when possible). See the more information section below the table for definitions and explainations about the data.
What is a sewage spill?
People think of a spill as a large amount of oil or chemicals that usually comes from an industrial accident. However, for a sewage spill it can be anything from a slow, small leak in a sewer pipe, where only a few gallons leak out, to a large spill of millions of gallons of wastewater and bacteria. Sewage spills can be caused by many different issues, such as from a tree root that cracks a pipe, to a pipe blocked with “flushable” wipes, to a power outage that causes a pump to stop working. Because sewage flows continuously through complex plumbing networks, blockages or failures at any point can cause a spill.
Specifically, a sewage spill is defined as the intentional or accidental discharge of untreated or undertreated wastewater that comes from a permitted sewage treatment facility or a collection system.
Why it matters
Raw or partially treated sewage can include fecal coliform bacteria, pathogens, solids, and toxins — all of which can harm people, fish, and wildlife if touched or swallowed. Children and the elderly may be more vulnerable to waterborne illnesses such as gastroenteritis, skin rashes, and upper respiratory infections. We encourage you to contact your local health agency for any warnings about recreational contact with waterbodies, and the Department of Health for any warnings about fish or shellfish consumption.
What causes a sewage spill?
Just like fats, oils, and grease (also called FOG) can clog your arteries, they can clog sewer pipes.
Tree roots, decaying pipe material, or a wayward backhoe can crack open pipes causing spills
All wipes clog pipes, even the ones labeled as "flushable."
- Pipe blockages – fats, oils, and grease (FOG) and wipes
- Broken pipes – tree roots, decaying pipe material, or a wayward backhoe can crack open pipes
- Excess water – rain or groundwater getting into the wastewater pipes can overload the pipes or pump stations
- Power or mechanical failures at pump stations or treatment facilities
- Improper treatment facility operation
- Maintenance issues at the treatment facility or the collection system
Water has to keep flowing
Wastewater facilities use multiple technologies and steps to remove solids, bacteria, chemicals, and pollutants from sewage. Unlike a home waterline, a wastewater system has no emergency shut-off valve. If a failure occurs, the wastewater must keep flowing.
We regulate wastewater treatment facilities using permits that specify limits, monitoring, and plans for when things go wrong, like an equipment failure or flooding that might cause sewage spills. Because the flow cannot be completely stopped, many treatment facilities feature built-in bypasses to reroute wastewater around certain treatment stages during emergencies. Intentionally bypassing a part of treatment—which creates a sewage spill—can minimize facility damage and speed up repairs.
Depending on where the spill occurs, the wastewater may be completely untreated (raw sewage) or partially treated. See the more information section below the Sewage Spill List for more information about treatment levels.
Our role in responding to sewage spills
When a sewage spill is reported to us, directly or through our Environmental Reporting and Tracking System (ERTS), we investigate and respond accordingly. We review the facts about what led to the spill, how the facility responded to the spill, and what the facility plans to do to prevent the spill from happening again. We use education, technical assistance, and cooperation-based programs to achieve voluntary compliance first before moving to formal enforcement.
When a community needs financial assistance to make treatment facility upgrades or conduct special studies, they can apply for funding through our Water Quality Combined Funding Program. This program provides millions of dollars of financial assistance each year for wastewater infrastructure improvement projects across the state.
List of sewage spills
*Note: This information is provided as it has been reported. It has not been independently verified by Ecology. The information is provided for educational, informational, and research purposes. This information is not independently verified, and no guarantee is made regarding the information’s accuracy, completeness, or fitness for a particular purpose.
More information
To help you understand the information in the table, we have included more information and definitions below.
Related links
Contact information
Stacy James
Communications
Stacy.james@ecy.wa.gov
360-584-8647