California Laws 19 Jul, 2023

California - Voluntary Vessel Speed Reduction

Erin Walton
Erin Walton
Assistant Corporate Director

The USCG, EPA and NOAA make an annual request that all vessels 300 GT or larger reduce speeds to 10 knots when transiting within the designated VSR (Vessel Speed Reduction) zones along the California coast. All transits by vessels 300 GT or larger are analysed by NOAA via AIS data provided by USCG to assess the industry's cooperation.


The program’s goal is to reduce the risk of fatal ship strikes to endangered blue, fin and humpback whales while also reducing ocean noise and increasing air quality for coastal communities.

The program runs from 1 May -15 December. As of 2023, the San Francisco VSR zone has been extended to include all of Monterey Bay National Marine Sanctuary.

Owners receive public recognition based on the percent of distance travelled through the VSR zones at 10 knots or less and with an average speed of 12 knots or less.

Further details including VSR zone maps and enrolment links can be found on the website of Protecting Blue Whales and Blue Skies, a partnership of federal and local government agencies as well as non-profit organisations. Any company who operates container, car carrier, bulk cargo or tanker vessels that pass through the VSR zones is eligible to enrol.

Members wishing to take part in the program are reminded to ensure that the liberty to voluntarily reduce speed is available in all applicable charterparties and reflected clearly in bills of lading.