The California State Lands Commission is implementing an emergency rule that amends Article 4.7 of Chapter 1, Division 3 of Title 2 of the California Code of Regulations. The emergency rule was effective starting on June 18, 2025.

This emergency rule requires vessels with ballast water sourced from waters with a measured salinity of less than 18 parts per thousand (ppt; i.e., 18 grams of salt per kilogram of water) to conduct ballast water exchange prior to discharging at California’s fresh and brackish water. This requirement is in addition to meeting existing California ballast water discharge performance standards(^*).

For more details, please refer to the California State Lands Commission website.

^*performance standards: Title 2, Cal. Code Regs. Section 2293