Connecticut State Department of Public Health

Information for Water Quality Monitoring

Distribution System Monitoring

Total Coliform

  • Water systems must continue to collect total coliform samples throughout the distribution system as required.
  • If a routine sample location is not available, an alternate sampling location may be selected that best represents the water quality at the location being replaced.
  • An alternate location can include an outside tap or other location that will not jeopardize the health and well-being of the sample collector and the building occupants.If an outside tap is used, sampling protocols should be followed to ensure that the tap is properly cleaned and flushed prior to collecting a sample.
    • Sampling at the alternate location should continue at the same frequency as the original routine location.
    • If the alternate location is within 5 service connections of the original routine location, the sample results should be reported using the Sampling Point ID Number of the original routine location.
    • If an alternate location cannot be located within 5 service connections of the original location, a new Sampling Point ID Number is required. The proposed alternate sampling location must be submitted to the DPH DWS on the Sample Point Inventory Spreadsheet along with a justification for review. 
    • If an outside tap or spigot has been selected and an alternate location, follow the guidance on the Collection of Total Coliform Samples from Outside Sill Cocks, Spigots or Garden Hydrants
  • As a last resort, systems may also use a hydrant sampler to create alternate sampling locations throughout the distribution system. Additional information on hydrant samplers can found on EPA’s website: https://www.epa.gov/sdwa/hydrant-sampler-procedure-and-parts-lists.
  • If a sample collected from an alternate location is total coliform positive, 3 repeat samples will be required as usual.

Disinfection By-Products

  • Water systems must continue to collect disinfection by-product sample (i.e. Total Trihalomethanes and Total Haloacetic Acids) in accordance with the water system’s approved Stage 2 monitoring plan.
  • If a routine site is not available, an alternate sampling location may be selected as long as it represents the same water quality as the location being replaced.
  • If the alternate location is within 5 service connections of the original routine location, the sample results should be reported using the Sampling Point ID Number of the original routine location.
  • If an alternate location cannot be located within 5 service connections of the original location, the DPH DWS should be consulted.

Entry Point and Source Water Monitoring

  • Water systems must continue to collect Entry Point and Source Water samples as required.
  • As usual, if a source or entry point that requires monitoring is not operational during any month or quarter, the DPH DWS must be notified.
  • If an entry point sampling location is not available, the DPH DWS must be notified.

Operational Monitoring for Treatment Plants

  • When required by the Regulations of Connecticut State Agencies (RCSA), Operational measurements and monitoring must continue and all operational ranges must be complied with.
  • If a system is not able to comply with the operational monitoring requirements, the DPH DWS must be notified.

Lead and Copper Rule

Non-Community Water Systems

  • Non-community public water systems with facilities that are fully closed and water is not available for public consumption should notify the Department of the date which the PWS closes and also when it reopens (once applicable).
  • The use of alternate locations, as described above, may also be considered.

All requests for the use of alternate sampling locations or notifications of PWS closure should be emailed to DWDcompliance@ct.gov.