Approximately 60% of Nova Scotians receive treated drinking water from central groundwater or surface water supplies operated by municipal water utilities. Municipal public drinking water supplies are responsible for the delivery of water in accordance with provincial standards and for meeting their requirements for due diligence – making sure the water they deliver is properly managed and protected.
Approvals and Responsibilities
Nova Scotia Environment and Climate Change is responsible for issuing approvals for the construction and operation of water treatment and distribution facilities under the Activities Designation Regulations. In order to obtain an approval, a completed application form (PDF:1008k) and supporting documentation must be submitted to the Department.
Active municipal public drinking water supplies are required to complete a System Assessment Report by April 1, 2023 to verify that each system is technically capable of achieving current environmental and public heath standards.
System Assessment Report and Terms of Reference
The purpose of a System Assessment Report is to verify that municipal public drinking water supplies meet:
- current environmental and public health standards, which are frequently updated and enhanced for public health protection;
- the minimum requirements set out in the Nova Scotia Treatment Standards for Municipal Drinking Water Systems, as amended from time to time.
A Terms of Reference (PDF:604k) document and Terms of Reference Checklist (PDF:960k) have been prepared to assist Approval Holders prepare these reports
Treatment Standards
The Nova Scotia Treatment Standards for Municipal Drinking Water Systems outline the requirements for municipal public drinking water supplies that use surface water, groundwater under the direct influence of surface water (GUDI), secure groundwater (non-GUDI), and that distribute treated water purchased from another municipal public drinking water supply.
The Treatment Standards document is available below as one large document or in nine sections.
The complete document is available here (PDF:4.2mb)
Part I to VII of the Treatment Standards (PDF:464k) sets out the minimum requirements that apply to municipal public drinking water supplies in Nova Scotia. This includes source water protection, adequate treatment and distribution, operations and management.
Appendix A - GUDI Protocol (PDF:376k) outlines the process to be used to identify whether groundwater supplies are under the direct influence of surface water (GUDI).
MPA sampling modifications recommended by the Department are outlined in the following document:
Approved Modifications to the MPA Consensus Method for use in Nova Scotia (PDF:174k)
Appendix B - Natural Filtration Guidelines (PDF:119k) outlines the criteria for determining which groundwater supplies that are under the direct influence of surface water (GUDI) may be assigned a log removal credit for the natural filtration capacity of the aquifer. GUDI supplies that are assigned a log removal credit may apply the credit towards meeting the requirements of the Treatment Standard.
Appendix C - Process for Assigning Pathogen Log Reduction Credits (PDF:156k) outlines minimum treatment requirements and the process for assigning pathogen log reduction credits for enteric viruses and protozoa.
Appendix D - Log Inactivation Information and Tables (PDF:3mb) provides log inactivation values for free chlorine, chlorine dioxide, ozone and UV disinfection.
Appendix E - Baffling Factors (PDF:174k) provides baffling factors for sample contact chamber designs.
Appendix F - Sample CT Calculation (PDF:168k) provides guidance regarding how to calculate CT.
Appendix G - Technical Considerations for Filtration and Disinfection (PDF:148k) outlines specific requirements that apply for ultraviolet (UV) light disinfection, on-site generation of sodium hypochlorite, and membrane filtration.
Appendix H - Sampling Requirements (PDF:239k) outlines sampling requirements municipal public drinking water supplies must adhere to based on source water type.
Nova Scotia Environment has published a guide on Developing a Municipal Source Water Protection Plan. The document Designation of a Protected Water Area was developed to help municipalities and the general public better understand the potential role of designation in a municipal source water protection plan.
Our page on water withdrawal approvals has more information on how to apply for a surface water or groundwater withdrawal approval.
If you are planning any activities in these areas please contact the contact the appropriate municipal water utility: Municipal Drinking Water Supplies of Nova Scotia (PDF:1.1mb).
Municipal Public Drinking Water Supply Oversight
The Nova Scotia Utility and Review Board and Nova Scotia Environment have published a guide on municipal water utility oversight.
The guide was developed to help municipalities better understand their roles and responsibilities under the Public Utilities Act (administered by the Board) and the Environment Act (administered by Nova Scotia Environment).
- Guide: Municipal Water Utility Oversight (PDF:833k)
- Nova Scotia Utility and Review Board - nsuarb.novascotia.ca
Guidelines and Resources For Municipal Public Drinking Water Supplies
The following is a complication of resources to help municipal public drinking water supplies comply with the terms and conditions of their approval and the Water and Wastewater Facilities and Public Drinking Water Supplies Regulations
- Guidelines for Monitoring Public Drinking Water Supplies, Part I: Municipal Public Drinking Water Supplies (PDF:487k)
- A Guide to Assist Nova Scotia Municipal Water Works Prepare Annual Sampling Plans (PDF:1.5mb)
- Lead and Copper Management Toolkit (PDF:1.2mb)
- Lead and Copper Management (PDF:982k)
- A Guide to Assist Nova Scotia Municipal Water Works Develop A Discharge Management Plan for Filter Backwash Discharges to Land (PDF:4mb)
- A Guide to Assist Nova Scotia Municipal Water Works Develop Site Specific Aluminum Effluent Discharge Criteria for Filter Backwash Discharges Into A Freshwater Watercourse (PDF:3.9mb)
- Cross Connection Control Program (PDF:463k)
- Atlantic Canada Water Supply Guidelines
- Water Utility Standard Operating Procedures and Contingency Plans Guidance (PDF:584k)
- Maintaining Distribution System Water Quality (PDF:30k)
- Safe Drinking Water for Public Water Systems