Toxic algae which if eaten has the potential to be lethal to dogs has been spotted in a Chesterfield reservoir.
Pictures show waters at the Linacre reservoirs has gone a turquoise colour, which walkers claim is due to algae, which can cause breathing problems, lasting liver damage and death.
Locals have submitted complaints to the water company in charge of that area, claiming "there is completely insufficient signage and wouldn't want any other dog owner to experience what I have or worse".
An anonymous post on Facebook, read: "I let my dog drink from the lower reservoir as the water looked normal and at that point there was nothing to suggest otherwise.
"The middle and upper reservoirs looked rather green so I didn’t let my dog near them.
"Only after getting two thirds of the way round the reservoirs did I come across a small sign (that could have been easily missed if I was walking in the opposite direction) saying that blue green algae was present in the reservoirs.
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"I phoned the vet who said to bring my dog in immediately as if it was not dealt with fast enough it could have lasting affects.
"My poor dog was forced to throw up to get it out of her system and will be having to go back for blood tests to ensure it’s not affected her liver."
A Severn Trent spokesperson said: "The algae is naturally occurring, and forms on all types of open water, it's caused by nutrient rich water combined with prolonged warm weather and direct sunlight, so we see it in summer.
"This is why we have extensive signage out across all of our sites, as under no circumstances do we want people, or pets going into the water - not only for the algae but because it's dangerous to swim in also."
