Chinook Salmon on Mokelumne River  Credit: EBMUD

S.A.L.M.O.N Act Aims to Address Urgent Threat to Native Salmon Species

March 23, 2024 - San Mateo – On Tuesday, legislation to protect California's iconic salmon and steelhead trout authored by Assemblymember Diane Papan (D-San Mateo) was approved by the Assembly Committee on Transportation with a bipartisan vote. The S.A.L.M.O.N Act (Stormwater Anti-Lethal Measures for Our Natives Act), would mandate the development and implementation of a regional strategy by the Department of Transportation (Caltrans) to eliminate 6PPD from stormwater discharges into specified salmon and steelhead trout-bearing surface waters of the state.

"The S.A.L.M.O.N Act will begin the process of safeguarding California's native salmon species and the $500 million fishing industry that relies upon it,” said Papan. “The threat posed by 6PPD is significant and this legislation provides the first step to protect our environment, economy, and cultural heritage."

For over two decades, researchers have observed a link between stormwater discharge and salmon mortality, known as the "Coho mortality phenomenon." In 2020, a pivotal report from the University of Washington identified 6PPD, a toxic chemical found in most motor vehicle tires, as the culprit behind the alarming fish kills associated with stormwater runoff. When exposed, 6PPD transforms into 6PPD-quinone, compromising the blood-brain barrier of salmon and resulting in rapid fatalities.

The S.A.L.M.O.N Act will direct Caltrans to study, implement and asses the cost-effectiveness of biofiltration and bioretention systems, proven stormwater filtration practices, to prevent the runoff of 6PPD into critical salmon and steelhead trout habitats. Successful implementation could provide a roadmap to utilize these crucial stormwater management practices statewide.

"The decline of native salmon has far-reaching consequences affecting not only our environment but also the livelihoods of thousands and the cultural traditions of Indigenous tribes,” said Papan. “The S.A.L.M.O.N Act prioritizes the health of our waterways, wildlife and the well-being of our communities."

Assembly Bill 1798 will be heard in the in the Assembly Committee on Environmental Safety and Toxic Materials in the coming weeks.
Source: Assemblymember Diane Papan