The bill amends Chapter 46-15.3 of the General Laws, titled "Public Drinking Water Supply System Protection," by introducing a new section, 46-15.3-5.2, which mandates that all parties involved in the supply, transmission, and distribution of drinking water prepare, maintain, and carry out a water supply resilience plan by January 1, 2026. The purpose of the resilience plan is to identify risks and provide assessments and emergency response strategies to enhance the resilience of water supply systems against natural hazards and environmental impacts. This requirement applies to water suppliers, including municipalities, municipal departments and agencies, districts, authorities, or other entities engaged in the supply, treatment, transmission, or distribution of drinking water on a wholesale or retail basis, that handle more than 50 million gallons of water annually.

The initial risk assessment required by this section must be completed no later than July 1, 2026, and the results must be provided to the governor, speaker of the house, president of the senate, the director of the department of health, and the director of the department of environmental management. The assessment must include, but is not limited to, the risks to the water supply system from natural hazards and environmental impacts, the resilience of infrastructure, financial considerations, the use and handling of chemicals, and operational practices.

The resilience plans must document coordination with other nearby water suppliers and operators of wastewater treatment and disposal facilities, align with applicable local comprehensive plans, and be integrated into the water supply plans of the municipalities involved. The plans must designate responsible parties for necessary actions and the timeline for implementation. Water suppliers are required to utilize methods to implement measures necessary to achieve the objectives of this section and document the effectiveness of any measures included in their plans.

Within six months of the initial assessment, every water supplier must provide a response plan to address the issues raised in the assessment to the directors of the department of health and the department of environmental management. The assessment and response plan must be updated every three years from the initial assessment, with a report on the updated assessment delivered to the governor, speaker of the house, senate president, and director of the department of health. The act will take effect upon passage.