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Drinking Water Regulations and Rules

Oregon Drinking Water Regulations

  • Drinking Water Rules
    Oregon's Drinking Water Quality Act and Administrative Rules for Public Water Systems serve to ensure safe drinking water for Oregonians.

Rule Implementation Guidance

The Lead and Copper Rule applies to all community (CWS) and non-transient (NTNC) public water systems. EPA adopted revisions to the Lead and Copper Rule in 2021 that include a requirement for public water systems to conduct inventories of service lines and to identify service line material type. The intent of the service line inventory requirement is to identify those service lines made of lead so that they can be scheduled for removal and replacement.

Public water systems must conduct an inventory of all service lines, on both the water system side and the homeowner side of the meter, and to submit the results to OHA–Drinking Water Services (DWS) by October 16, 2024.

Oregon Very Small Systems

Effective January 1, 2022, water systems serving 4 to 14 service connections and commercial or public premises used by 10 to 24 people at least 60 days per year have been renamed Oregon Very Small (OVS) from State Regulated. New rules are now implemented for Oregon Very Small (OVS) systems that retain important public health protections and are more achievable for water suppliers with limited resources.

Long Term 2 Enhanced Surface Water Treatment Rule (LT2)
The Long Term 2 Enhanced Surface Water Treatment Rule (LT2) rule applies to all public water systems that use surface water or groundwater under the direct influence of surface water (GWUDI). The purpose of the rule is to ensure adequate treatment of surface water sources with higher levels of Cryptosporidium and to address uncovered finished water reservoirs.

The Groundwater Rule (GWR) applies to all public water systems that use groundwater sources or purchase groundwater. The primary purpose of the rule is to protect public health from bacterial and viral pathogens in public groundwater systems.



Reduction of Lead in Drinking Water Act

The Reduction of Lead in Drinking Water Act amends the Safe Drinking Water Act regarding the use and introduction into commerce of lead pipes, plumbing fittings or fixtures, solder and flux. The law is effective January 4, 2014. EPA has provided the following document to assist manufacturers, retailers, plumbers and consumers in understanding the changes to the law:


Revised Coliform Monitoring Requirements
These regulations apply to all public water systems with the intent of minimizing potential pathways for fecal contamination to enter distribution systems and to better protect the public from waterborne illness. The coliform monitoring revisions under this rule do not alter the source water monitoring required for groundwater systems. Changes to the revised rules are summarized below with links to additional resources for reference.

Stage 2 Disinfection Byproducts Rule
The Stage 2 Disinfection Byproducts Rule (DBPR) applies to all community and non-transient non-community water systems that add a primary or residual disinfectant other than ultraviolet light (UV), or deliver water that has been treated with a primary or residual disinfectant other than UV. Systems that purchase disinfected water are included in this rule. The Stage 2 DBPR builds on the existing Stage 1 rule and provides increased health protection.