California’s SB 601: Protecting Water Quality in a Post-Sackett World

05.06.2025

The Challenge:

The U.S. Supreme Court's decision in Sackett v. EPA (2023) significantly narrowed the scope of regulatory authority under the federal Clean Water Act ("CWA"). This ruling redefined “waters of the United States” to include only relatively permanent, standing, or continuously flowing water bodies forming geological features ordinarily described as streams, oceans, rivers, and lakes. This change curtailed federal protection for many of California's streams and wetlands.

California's Response: Senate Bill 601

To preserve pre-Sackett water quality protections for California’s streams and wetlands, including “adjacent” wetlands, the Right of Clean Water Act, Senate Bill 609 ("SB 601") was introduced and continues to advance in the California State Legislature. This bill amends the Porter Cologne Water Quality Control Act (“Porter Cologne Act”) to restructure the state’s water quality regulatory framework so that California continues to regulate streams and wetlands that lost protection under the CWA due to Sackett. California may regulate the quality of waters of the state as a matter of state law.

Key Provisions of SB 601:

Nexus Waters: SB 601 adds a new category of state waters – “nexus waters” – to the Porter Cologne Act, specifically to Chapter 5.5 of Title 7 of the Water Code “Compliance with the Provisions of the Federal Water Pollution Control Act of 1972.” These are defined broadly as all waters of the state that are navigable waters, except nonjurisdictional waters determined by the CWA prior to Sackett, nonjurisdictional waters of the state, and other associated waters (e.g., groundwater). The intent of the “all…, except” definition of “nexus waters” is to achieve the stated goal of SB 601 – “to restore and retain protections afforded to certain waters of the state prior to May 25, 2023.”
Federal Discharge Requirements: SB 601 applies the same federal discharge requirements (i.e., federal standards), under the federal CWA, including NPDES permits, to “nexus waters” as that term would be added by amendments to the California Water Code. This aims to prevent entities from seeking less stringent state Waste Discharge Requirement (WDR) permits to avoid federal oversight. To implement the requirements of SB 601, the State Water Board and Regional Water Boards would need to include “nexus waters” in all processes pursuant to the federal CWA, including but not limited to the California Integrated Report and the establishment of total maximum daily loads.
Continuity of Standards: For the sake of continuity, SB 601 would also provide that any water quality standard applicable to “nexus waters” that was submitted to, approved by, or awaiting approval by the U.S. EPA or State Water Board prior to January 19, 2025 (i.e., President Biden’s last day in office), remain in effect unless a more stringent standard is adopted. Additionally, the State Water Board would be required to adopt a primary drinking water standard at least as stringent as the national primary drinking water standard adopted by the U.S. EPA that was in effect on January 19, 2025.
Enhanced Compliance and Enforcement: To ensure compliance with SB 601, regulated industries would be required to demonstrate enrollment with the NPDES or the WDR permit programs when applying to a city or county for an initial business license, equivalent instrument, or permit, including but not limited to building and construction permits, consistent with the requirements in the Business and Professions Code. It also significantly expands the enforcement authority for the State Water Boards and Regional Water Boards and allows for citizen suits for unlawful discharges into "nexus waters." Any violations of the State Water Board and/or Regional Water Board orders, permits, or other waste discharge requirements, would be subject to civil liability. By statute, courts could impose up to $15,000 for each day the violation occurs, and the State Water Board and/or Regional Water Boards could administratively impose civil liability up to $5,000 for each day the violation occurs. The civil monetary penalties would be subject to inflationary adjustments. SB 601 would also allow for citizen suits – an enforcement action brought in superior court by a person in the public’s interest.

Why This Matters:

SB 601 represents an effort by California to fill a perceived void in protection of water resources in the wake of federal regulatory changes. For the water industry, this means potentially stricter regulations, increased enforcement, and the possibility of citizen litigation. It is crucial to stay informed and prepared for these changes to ensure compliance and protect California's water quality.

If your agency has questions about SB 601 or the contents of this Alert, please contact the authors of this Alert or your usual AALRR counsel.