Algae or Sediment in the Sea?

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Reassurances have been given about the water quality in a Pembrokeshire harbour on the eve of a major triathlon there.

Remember that scorching weather that caught us all by surprise and had us melting, just before the rain came back and the normal cold weather returned?

It brought with it what looked like a worrying algal bloom which kept some swimmers out of Goodwick harbour, and other popular swimming places, just ahead of the Wales Triathalon, over last weekend.

Despite some complaining that dead shellfish and lugworms had washed up in the harbour, Natural Resources Wales (NRW) declared no evidence of pollution and by 5 June, the algae seemed to have dissipated. Almost certainly the heat caused what is a natural phenomenon to occur, but there is no doubt that chemical fertilisers and slurry might accelerate the algae growth.

The bloom can cause a scum to form on the surface of the water which is smelly and unpleasant but Public Health Wales says that this is not normally a hazard to health, except when toxins are present.

People have been advised not to swim when the bloom is present just in case it is hazardous, although NRW undertook an investigation and determined  that this occurrence may not have been bloom, but sediment stirred up by weather and tide, and that it was not polluting.

If you are concerned by what looks like algal bloom, you can report it to NRW on 0300 065 3000.