Backflow Laws: Connecticut
Connecticut Backflow Prevention Laws, Regulations, and Compliance Requirements
Connecticut's backflow prevention requirements are established in the Regulations of Connecticut State Agencies at Section 19-13-B38a and administered by the Connecticut Department of Public Health (DPH) Drinking Water Section. Connecticut requires RPZ backflow preventers on all high-hazard service connections, mandates annual cross-connection survey reports, and administers its own tester and inspector certification programs. This guide covers state regulations, MDC Hartford's large utility program, Connecticut Water Company requirements, and Aquarion Water requirements.
Connecticut State Regulatory Framework
Connecticut’s cross-connection control requirements are grounded in the Regulations of Connecticut State Agencies at Section 19-13-B38a — Permissible arrangements for connections to public water supply lines — administered by the Connecticut DPH Drinking Water Section. Connecticut General Statutes Section 19a-209a provides the legislative authority. Connecticut holds EPA primacy under the federal Safe Drinking Water Act.
Connecticut has had an active cross-connection control program since 1976, initially applying primarily to larger public water systems (serving more than 1,000 consumers). The DPH’s Drinking Water Section administers tester and inspector certification, maintains the state database of certified personnel, and requires annual cross-connection survey reports from water systems.
Annual reporting: Connecticut water systems must submit an annual cross-connection survey report to DPH by March 1 covering the preceding calendar year. This makes Connecticut a high-regulation state with formal state-level oversight of utility program compliance.
Assembly Type Requirements Under Section 19-13-B38a
Connecticut’s regulations establish a detailed matrix of required assembly types by hazard and application:
Reduced Pressure Principle backflow preventers (RPD/RPZ) are mandatory for: fire sprinkler systems with chemical additions or foam systems; pressurized water systems on ships; car wash facilities with pressure boosting; irrigation systems where chemicals are added; boiler systems where chemicals are added; heat exchangers and solar heating systems where chemicals are added; plating tanks or areas (with no potable water use allowed downstream); and lines to facilities where toxic or objectionable substances are handled in addition to other required protection.
Double Check Valve Assemblies (DCVA) are required on fire sprinkler systems with Siamese connections unless chemicals are added (in which case RPZ is required). As of July 1, 1999, RPZ is required on all lines to fire sprinkler systems with Siamese connections, except existing systems that already have a DCVA installed.
Air vent type backflow preventers, RPD, or air gap are required for: boiler systems without chemical additions; carbonators for beverage machines, water conditioning, and commercial ice making; solar heating without chemical additions; and storage tanks for fire protection without chemical additions.
For irrigation and lawn sprinkler systems: Connecticut state law only approves PVB (Pressure Vacuum Breaker) and RPZ type backflow preventers for irrigation systems. Annual testing of backflow devices is required by state law, with results sent to the water purveyor.
DPH Backflow Tester Certification — NEWWA-Based
Connecticut requires that backflow prevention device testing be performed by a person who has completed and passed a DPH-approved course on testing backflow preventers. The New England Water Works Association (NEWWA) is the primary DPH-approved course provider. Individuals must register through NEWWA for scheduled courses. Upon passing, an Application for Certification must be submitted to DPH within one year of the exam results.
Connecticut also certifies Cross-Connection Survey Inspectors — a separate credential for inspectors who assess buildings for cross-connections. In lieu of a DPH-approved inspection course, a tester who has also completed the testing course may receive field training from a qualified Cross-Connection Inspector. The DPH Drinking Water Section maintains a database of certified personnel accessible through the state e-Licensing website at elicense.ct.gov. Currently over 690 individuals hold active DPH certificates as testers or tester/inspectors.
Connecticut's March 1 Annual Report Deadline
Connecticut water systems must submit their annual cross-connection survey report by March 1 for the preceding calendar year. This annual reporting requirement is a key reason Connecticut is classified nationally as a high-regulation state. Property owners whose assemblies are overdue for testing contribute to utility non-compliance with this reporting obligation — which motivates active utility enforcement. If you receive a compliance notice from a Connecticut water utility, the March 1 reporting deadline creates an urgency that utilities enforce seriously.
Major Water Purveyors in Connecticut
The Metropolitan District Commission (MDC)
MDC serves approximately 400,000 people in the Greater Hartford area across eight member towns. MDC’s cross-connection control program operates under Ordinance Section W-12 and the Cross-Connection Control and Backflow Prevention Manual of Practice (District Ordinance Section W12m). Connecticut cross-connection regulations require property owners to notify MDC and obtain approval before constructing or installing any equipment or systems capable of introducing contaminants into MDC’s drinking water system.
MDC’s program has expanded to include fire suppression systems, lawn irrigation systems, marinas, boilers, solar heat, geothermal wells, lawn irrigation wells, ice machines, and facilities using chemicals within the premises. MDC inspects over 3,300 commercial, industrial, residential, and health facilities annually, examining plumbing connections and testing backflow preventers, with results reported to DPH.
Connecticut Water Company
Connecticut Water Company (United Water/Connecticut Water) serves approximately 375,000 people across Connecticut’s shoreline towns, Chambersburg area, and others. Connecticut Water’s Rules and Regulations (updated July 2024) require DPH-approved backflow prevention assemblies at all service connections where cross-connection hazards are identified. The utility requires RPZ on lines to fire sprinkler systems with Siamese connections per state code, and DCVAs on appropriate connections per the 19-13-B38a matrix. Connecticut Water, Crystal Water, and Unionville Water share regulatory requirements under their utility holding structure.
Aquarion Water Company
Aquarion Water Company serves approximately 230,000 customers primarily in Fairfield County and portions of New Haven and Litchfield counties. Aquarion administers a cross-connection control program aligned with DPH requirements. Annual testing by DPH-certified testers is required, with results reported to Aquarion and included in Aquarion’s annual DPH report.
South Central Connecticut Regional Water Authority (RWA)
RWA serves the New Haven area and surrounding communities. RWA inspects commercial, industrial, and residential health facilities and reports annually to DPH. Their program includes both containment (meter-level) and isolation (point-of-use) approaches where appropriate.
Connecticut's RPZ Requirement for High-Hazard Connections Is Among the Nation's Strictest
Connecticut’s requirement to install RPZ assemblies (called RPD in Connecticut regulations) on all high-hazard service connections is more prescriptive than many U.S. states in detailing the specific applications where RPZ is mandatory. Property owners with boilers (regardless of chemical use), fire suppression systems, car wash operations, solar heating, and chemical handling must confirm they have the correct assembly type — DCVAs are only acceptable in specifically enumerated lower-hazard applications.
Property Owner Compliance Summary for Connecticut
Assembly type: Confirm the correct assembly type per Section 19-13-B38a. High-hazard applications require RPZ. Irrigation requires only PVB or RPZ per Connecticut law.
Testing: Annual testing by DPH-certified tester. Results sent to your water purveyor.
Inspections: Buildings must be inspected for cross-connections by DPH-certified Cross-Connection Survey Inspectors or testers with appropriate credentials.
Records: Maintain test records. Retain documentation of any cross-connection assessments.
Find a Certified Backflow Tester in Connecticut
Find DPH-certified backflow testers and cross-connection survey inspectors at getyourbackflowtested.com/backflow-testing-near-me/connecticut-backflow-testing or through the state e-licensing portal at elicense.ct.gov.
Connecticut Regulatory Reference Links
| Resource / Agency | URL / Link Target |
|---|---|
CT DPH — Backflow Prevention and Cross-Connection Control | |
Section 19-13-B38a — Permissible arrangements (LII) | |
CT DPH — Cross Connection Control Manual | |
CT e-Licensing — Certified Tester Lookup | |
MDC — Cross Connections | |
Connecticut Water — Rules and Regulations (July 2024) | |
NEWWA — Backflow Tester Training (DPH-approved) |