Guide Private Water Supplies

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4. Sampling

  1. Single Private Dwellings: Will not require routine monitoring or a risk assessment. We can sample or risk assess at owner’s request, such as a house sale.
  2. Small Domestic Supplies: Will need a risk assessment a minimum of once every five years. Sampling will be based on the findings of the risk assessment.  Supplies will be sampled for five basic parameters and anything else that arises from the risk assessment.
  3. Large Supplies or Commercial Premises: Two types of monitoring will occur on these supplies:
      1. Check monitoring ensures the wholesomeness of the water, the frequency of check monitoring will depend on the amount of water used.
      2. Audit monitoring determines whether the water supply meets the relevant standards. The range of tests for audit monitoring is extensive and the amount of monitoring depends on the outcome of the risk assessment.
  4. Private Distribution Systems: Monitoring must be carried out according to the outcome of the risk assessment.

 Sampling by accredited samplers

As of July 2020, the Drinking Water Inspectorate made it a requirement for any person collecting, transporting and storing samples of private water supplies to be certified as an accredited sampler. Certified samplers must comply with ISO/IEC 17024.

East Devon District Council cannot accept any third-party private water sample results from unaccredited samplers. All annual regulatory water samples will have to be taken by the Council’s own accredited private water supplies team or a certified sampler.

Further information regarding accreditation can be found here: