A newly re-opened reservoir will not allow open water swimming for the time being after a suspected case of swimmer’s itch.
The Lisvane and Llanishen reservoirs in Cardiff will re-open to the public on Friday and the site is set to offer a number of outdoor activities.
Swimmers’ itch, also known as cercarial dermatitis, appears as a skin rash caused by an allergic reaction to certain microscopic parasites that infect some birds and mammals.
The rash is more frequently found during the summer months.
A spokesperson for Welsh Water said tests carries out over the past few months found the water quality at Llanishen reservoir was “excellent”.
“However, after one open water swimming session last week there was a report consistent with swimmers’ itch”, the spokesperson said.
“This can occur at open water sites where wildfowl and fresh water snails are present – both are at the reservoir.”
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The Victorian reservoirs have been transformed into health and wellbeing “hubs”.
The activities on offer will include sailing, canoeing, stand up paddle boarding and kayaking.
A two-storey visitor centre boasts views across the reservoirs.
It includes a cafe and meeting rooms, with a night-time restaurant also set to open at the centre in September.
The Weslh Water spokesperson added: “There haven’t been any other issues, but as a precautionary measure, we have paused open water swimming while we take further advice on the location of the open water swimming course – which is currently in shallow water where the risk of swimmers’ itch – which is quite common in open water – is higher.”
