California’s voluntary vessel speed reduction programme has expanded across the state’s full coastline with 60 shipping lines enrolled for the 2026 season, according to Protecting Blue Whales and Blue Skies.
The programme expanded on 1 July from the Oregon border to the Mexico border, after the 2026 season began on Earth Day, 22 April. It asks ocean-going vessels of 300 gross tons or more to travel at 10 knots or less inside the zone through 31 December 2026.
The expanded 2026 zone has reached an 80% cumulative cooperation rate in the early part of the season. In the first six weeks, 250 participating ships sailed more than 73,000 nautical miles at “whale-safer speeds” of 10 knots or less. The wider zone is intended to reduce the risk of fatal ship strikes on endangered whales, as well as underwater radiated noise and air pollution affecting coastal communities.
Newly eligible cruise lines have been brought into the programme for the 2026 season, although the announcement did not identify all 60 enrolled shipping lines. “The enrollment and cooperation data we are already seeing in the 2026 season reveal meaningful momentum as this program transitions to its largest zone area to-date,” said Jess Morten, director of marine resource protection for the California Marine Sanctuary Foundation.
The coastwide expansion follows California Assembly Bill 14, signed by Governor Gavin Newsom on 11 October 2025. The law directed the Ocean Protection Council to participate, subject to funding, as a stakeholder and adviser in support of a statewide voluntary vessel speed reduction and sustainable shipping programme for the California coast.
The law applies to vessels of 300 gross tons or greater and allows incentives to be linked to the share of distance travelled at reduced speeds, including speed zones of 10 knots or less. It also requires participating air pollution control districts and air quality management districts to report to the Legislature on implementation by 31 December 2029.
The programme began as a regional voluntary effort in 2014, administered by California air districts, federal marine sanctuary partners, marine sanctuary foundations and environmental groups. Through 2024, it had recorded 1,596,008 slow-speed miles, cut nitrogen oxides by 5,903 tons, reduced regional greenhouse gas emissions by 204,661 metric tons and lowered estimated whale-strike risk by 50% during prime migration season in affected coastal areas.
In the 2025 season, 787 vessels from 44 global shipping lines voluntarily reduced speeds over more than 481,000 nautical miles off California. The programme’s 2025 analysis showed reductions of 1,491 tons of nitrogen oxides, 8.9 tons of diesel particulate matter, 37 tons of sulphur oxides and 55,771 metric tons of greenhouse gases.
Protecting Blue Whales and Blue Skies is a collaborative partnership rather than a commercial company. Its partners include the California Marine Sanctuary Foundation; the Bay Area Air Quality Management District; Santa Barbara County, Ventura County and San Luis Obispo County Air Pollution Control Districts; Monterey Bay Air Resources District; Channel Islands, Monterey Bay, Greater Farallones and Cordell Bank National Marine Sanctuaries; and Benioff Ocean Science Laboratory.