Regional water regulators announced Thursday a proposed $17 million in penalties for the owners and operators of a Carson warehouse identified as the source of material that caused noxious odors to emanate from the Dominguez Channel for weeks, sickening residents across a swath of Long Beach and Carson.

The proposed fine against Day to Day Imports Inc. and Virgin Scent Inc.—doing business as ArtNaturals—and warehouse owner Liberty Property Limited Partnership and its parent company Prologis Inc. is the result of a monthslong investigation by the Los Angeles Water Quality Control Board into the noxious smell, which was traced to organic material decaying in the channel. The result was a rotten-egg-type smell that wafted over a region including Carson, Gardena, Torrance, Redondo Beach, Wilmington and Long Beach.

Some residents complained of headaches, burning eyes, nausea and other discomfort due to the odor.

If approved by the Los Angeles Water Board during its Oct. 12 meeting, the fine will be the largest ever imposed by the agency.

Residents rally outside of Carson City Hall to call on the City Council to address the foul-smelling Dominguez Channel on Thursday, Oct. 14, 2021. Photo by Crystal Niebla.

According to regulators, the companies stored large quantities of wellness and beauty products at the warehouse at 16325 S. Avalon Blvd. in Carson. On Sept. 30, 2021, a large fire started on the warehouse property, and efforts to extinguish the fire continued over several days.

The owner of a Carson warehouse insisted today that it quickly stepped in to begin remediation efforts after the fire.

“We vigorously dispute any suggestion by the Regional Board that Prologis and Liberty did not take appropriate actions as property owners following the Sept. 30 fire,” according to the company. “Neither Prologis nor Liberty caused the fire. Nevertheless, in the days following the fire, after the tenant Day to Day failed to clean up the fire debris, Liberty stepped forward to remove the debris and prevent stormwater runoff.  By the time the Regional Board issued its cleanup and abatement order 10 weeks later, we already had significant remedial actions well underway.”

The South Coast Air Quality Management District concluded last year that chemicals contained in the stored products, including ethanol, passed through the sewer system into the local flood control waterway, the Dominguez Channel. This was followed by the anaerobic decay of organic materials in the channel, which caused elevated levels of hydrogen sulfide to be discharged into the air.

Water Board officials said more than 4,000 complaints were ultimately received about the odor. The AQMD issued violation notices to the companies last year.

On Dec. 9, the Los Angeles Water Board issued a “cleanup and abatement order” to Day to Day Imports and Liberty Property Limited Partnership, requiring that all waste be removed by Dec. 31.

“To date, they have failed to complete all activities required by the order, leading the board’s prosecution team to propose an additional administrative civil liability of over $600,000 for this violation,” according to the Water Board.

The Los Angeles County Board of Supervisors last year declared a local emergency and the Department of Public Health conducted door-to-door outreach to more than 8,970 Carson residents, including medically fragile individuals. In addition, the Department of Public Works coordinated with multiple experts and spent an estimated $5.4 million on remediation and providing or reimbursing residents for air filters, air purifiers and temporary relocation.

Editor’s note: This story has been updated with a statement from the company that owns the warehouse.

How did the Dominguez Channel stench start? An interactive timeline