Guernsey Water moves fast to tackle 'pea soup'
THE reservoir was like a ‘pea soup’ a couple of weeks ago, said Guernsey Water quality risk manager Margaret McGuinness, but it is all under control now.
Traces of naturally occurring algae are always found in St Saviour’s reservoir, but the warmer weather has caused it to bloom, meaning action had to be taken.
‘The extended periods of hot weather we had made the blue-green algae bloom but we screened it out before it got into the water treatment system,’ said Mrs McGuinness.
Blue-green algae can be toxic, especially to dogs. Guernsey Water issued safety warnings and was able to eradicate the problem before it got in the drinking water.
The utility previously had taste and odour issues with the water in 2015.
‘We are trying to be as proactive as possible so as not to get that issue of earthy, musky tasting water again,’ said Mrs McGuinness.
She explained that there had been no real problems with algae since 2015 and although this is the worst year she has seen, the issues were resolved before it had any damaging effect on the drinking water.
Algae in the reservoir and quarries is controlled by a naturally occurring copper compound.
The compound does not affect any other elements in the water, such as the quality, or wildlife, it just gets rid of the algae.
Although there is no prevention for the naturally occurring aquatic plant, the Guernsey Water team test the water regularly and send samples to the UK for analysis.
Mrs McGuinness said: ‘We just have to be proactive.
‘We monitor the water all the time and react with a pretty easy method when algae blooms so it is not too much of a threat.’
