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    What is the delay between taking a sea water sample and the reporting on the Bathing Waters Explorer



    After a sample has been collected it is couriered to the laboratory for analysis by the next morning. The analysis is started within 24 hours of the sample being collected and takes a further 24 hours for preliminary results.

    The data then requires a further 3 days of analysis for a confirmed result. These sample results are then loaded onto our internal databases where the data is validated.

    This process, if validation passes, takes approximately 5 days after which they are transferred to the Bathing Water Explorer between 4-8 hours later. If the samples do not pass validation then this time can be greater.

    You can access the BW Explorer here: https://environment.data.gov.uk/bwq/profiles/#

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      I am trying to establish a safe way of assessing the quality of the bathing waters at my local beaches around Avon, Christchurch, Friars Cliff & Highcliffe as being a trainer at Christchurch Life Saving Club we have a responsibility to our membership to risk assess training in the sea for our members aged 7 - 65.
      I have been in contact with Wessex Water in relation to asset spills that I receive almost without fail after short periods of heavy rain.
      Wessex Water appear to be saying that despite the spills ,bathing water quality has not been affected as demonstrated in the results of testing by yourselves.
      As you state above your samples are randomly taken between 1st May & 30th September & therefore of no use to anyone needing to make an assessment on a daily basis.
      Surely with a huge increase in domestic tourism as a result of the pandemic it would be sensible from a public health perspective to take daily samples of the water from resort beaches or at least immediately after spills are notified to provide some reassurance?
      Is there no way to speed up the sample results ? 5 days post event is not really much good to anyone & members of the public will potentially already have been exposed to contaminated water.
      Many thanks,
      Simon Lancaster

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      Data Services Platform team

      Hi Simon,

      Apologies for the delay in getting back to you.

      The bathing water sample results on Swimfo are the from laboratory analysis and the majority of the 5 day lag is due to the time taken to incubate and grow the indicator bacteria we use to measure bathing water quality, plus the time it takes to transport the samples to the laboratory. These methods are the most accurate, and we are required by law to use them to assess the consistency and long term quality of the bathing water. These results are used to form the basis of the end of year classification and to identify any improvements that might be required, such as relocating sewage discharges and/or increasing treatment before discharge, rather than to give a short term view on the current water quality.

      To give an indication of more immediate water quality at bathing waters with variable results, we make a daily pollution risk forecast (PRF). All of the bathing waters you list are consistently classified as Excellent, with samples showing significant bacterial contamination to be very rare, so they are not part of the PRF system as there is very little variation in quality for the system to generate forecasts from.

      However, as for all bathing waters, on the rare occasion that a pollution incident is identified or reported that is likely to affect a bathing water, we would post this via Swimfo and at the beach.

      Dan, Data Services Platform team