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King County Washington home

August 27, 2026

Elevated lead contamination found on 23rd Avenue W in Interbay; pedestrians advised to avoid this block

A specialized contractor hired by the City of Seattle cleaned known contamination in the public right-of-way; additional testing is underway to determine the extent and source.


Summary:

Elevated levels of lead have been found in the public right-of-way along the 4200 block of 23rd Avenue W in Seattle’s Interbay neighborhood. A specialized contractor hired by the City of Seattle cleaned known areas of contamination in the roadway and a stormwater catch basin. Additional testing is underway to determine the extent and source of the contamination and whether further cleanup is needed.


While the investigation continues, Public Health – Seattle & King County recommends that pedestrians use alternate routes around the affected block, between W Commodore Way and W Elmore Street, when possible, and avoid the alley between 22nd Avenue W and 23rd Avenue W unless access is necessary. Pedestrians who have recently been in the area should take precautions to avoid tracking potentially contaminated dust into homes, vehicles and workplaces.

Story:

Elevated levels of lead have been found in the public right-of-way along the 4200 block of 23rd Avenue W in Seattle’s Interbay neighborhood, prompting cleanup of known contamination, additional environmental testing and precautionary public health guidance.

A specialized contractor hired by the City of Seattle cleaned known areas of contamination in the roadway and a stormwater catch basin on August 27. Additional testing is underway to determine whether contamination extends to other public areas and whether further cleanup is needed.

While that work continues, Public Health – Seattle & King County recommends that pedestrians use alternate routes around the 4200 block of 23rd Avenue W, between W Commodore Way and W Elmore Street, when possible. People should also avoid the alley between 22nd Avenue W and 23rd Avenue W unless access is necessary.

Lead-contaminated dust can be carried on shoes and on stroller and wheelchair wheels and tracked into homes, vehicles and workplaces. Pedestrians who have recently been in the affected area can take simple precautions, including removing shoes before entering their home and wiping stroller or wheelchair wheels with a damp cloth.

Initial findings

Seattle Public Utilities (SPU) collected samples from the roadway, and a stormwater catch basin along 23rd Avenue W in late July, followed by confirmatory testing in August.

Testing found 55.3 parts per million (ppm) of leachable lead in a roadway sample and 451 ppm in a catch basin sample. Both levels are above Washington State’s hazardous waste threshold of 5 ppm.

Additionally, Public Health collected water and dust samples at a nearby private daycare in mid-August. Samples collected in areas where children spend time did not show concerning levels of lead. Three of 11 samples showed levels above the Environmental Protection Agency’s (EPA) action levels – these three samples were collected in areas where children do not spend time. The daycare is working with Public Health to eliminate lead dust at the facility.

SPU hired a specialized contractor to clean the known areas of contamination in the public right-of-way and stormwater catch basin. That work was conducted on August 27. Additional sampling will help determine whether further cleanup or remediation of public areas is necessary.

The extent and source of the contamination have not yet been determined. City, county, state and federal agencies are conducting additional environmental testing and assessment to determine whether contamination is present in other locations, evaluate potential public exposure and identify any additional response or cleanup that may be necessary.

Investigation background

The environmental investigation followed concerns about occupational lead exposure at Dyno Battery, located in the area.

In March 2026, Washington State Department of Labor & Industries (L&I) fined Dyno Battery related to workplace conditions at the facility involving lead exposure. Battery production involves lead. In April, the Washington State Department of Health and L&I alerted Public Health – Seattle & King County (Public Health) about concerns of lead exposures at Dyno Battery and potential for workers to track lead home and expose their families. As part of the response, Public Health also became concerned about possible environmental contamination. Public Health contacted Seattle Public Utilities (SPU) in July, who conducted testing of soil and dust samples near the facility. Results confirming the high levels of lead came back in August.

Next steps

City, county, state, and federal officials are conducting more soil and water sampling to determine the extent and source of the pollution, the risk to the public and other businesses in the area, and any additional necessary remediation.

Public Health is in the process of working with employees at Dyno Battery to advise them on the risks of lead and how to obtain and understand blood lead tests. Public Health is also working with the daycare to reduce lead levels and inform parents about lead testing and steps to protect children from lead. Public Health will continue to work with businesses in the area to raise awareness of lead risks and ways to protect their health.

For more information about lead and your risk please visit the Public Health Insider. If you have questions about lead and your health, call the Washington Poison Center: (800) 222-1222.

Agencies involved and their roles in this response include:

  • King County Industrial Waste Program in the Department of Natural Resources and Parks: Regulation of commercial and industrial customers that discharge wastewater into the regional wastewater system. Media Contact: erzucco@kingcounty.gov
  • Public Health – Seattle & King County: Public health recommendations to protect people from environmental exposures and harmful substances – particularly protecting children. Media Contact: PHPIO@Kingcounty.gov
  • Puget Sound Clean Air Agency: Regulation of businesses with equipment, processes, or activities that emit air pollution. Media Contact: PhyllisM@pscleanair.gov, 206-689-4077
  • Seattle Department of Transportation: Manages public right of way and travel on city streets and sidewalks in the area. Media Contact: Media@seattle.gov, (206) 684-3151
  • Seattle Public Utilities: Enforces compliance with discharges related to its drainage and wastewater system. Media Contact: SPU_Media@seattle.gov, 206-446-8267
  • Washington State Department of Ecology: Hazardous Waste and Toxic Reduction program focuses on safe management and reduction of hazardous waste in Washington by enforcing Washington's toxics laws, including the Dangerous Waste regulations.  Media Contact: https://ecology.wa.gov/media
  • Washington State Department of Health: Site Assessment Program works to prevent and reduce exposure to harmful chemicals in the air, soil, or water.
    Media Contact: DOH-PIO@doh.wa.gov
  • Washington State Department of Labor & Industries: Protects the safety and health of the state’s workers and inspects workplaces for safety compliance.
    Media Contact: matt.ross@lni.wa.gov, (360) 706-4857