Milton Country Park issues warning to dog owners after water tests positive for blue-green algae

Blue-green algae has reared its unwelcome head at Milton Country Park, forcing staff at the popular dog-walking spot to erect signs and put fencing in place to inform owners.

The algae - more formally known as cyanobacteria - occurs naturally in lakes and rivers: to bloom it requires a combination of warm water temperatures, abundant sunlight and excessive nutrient levels, particularly phosphorus and nitrogen, in the water.

It can be fatal for dogs and one vet told the Cambridge Independent there had been at least one death from drinking this contaminated water this month. It can also make humans sick, although not to the point of hospitalisation.

Mick Woolhouse, executive director of Cambridge Sport Lakes Trust, which owns and runs Milton Country Park, said that the water near Todd’s Pit at Milton Country Park tested positive for the algae earlier this month.

“Todd’s Pit is near the café area,” says Mick. “We are very aware that the sandy beach leads down to the water and people let their dogs go in. But blue-green algae is a number one enemy, and we do have it at the park, but only in Todd’s Pit. This has been confirmed by our own sampling kits, which we use and send off to the Environment Agency for confirmation of the results.

“This current episode started on 11 June, and the water at Todd’s Pit has tested continually positive since then. Each time we get it, it takes about six to eight weeks to go away. There’s no treatment once you’ve got it – you have to let it run its course. With dogs their gut is ordinarily much more resilient than ours – it’s much more acidic – but blue-green algae is really not good for them.

“The signs went up straight away where the dogs typically go in the water. Dogs have to be on the lead anyway, as per the bylaws which were already in place when we took on the site in 2008, although there are certain areas where dogs can be off the lead provided they are under the control of the owner.

“Of course, there can be issues over what ‘under control’ is, but we don’t want dogs interfering with nesting sites and wildlife, so it depends on the specific dog and their owner.

“There’s a huge variation between the Labrador that shuffles alongside their owner and others who are much more inclined to go all over the place.”

Dog owners who do let their pets off the lead at any point must ensure they do not enter the water at Todd’s Pit.

“Blue-green algae is sporadic so once you’ve got it, it’s very hard to shift,” notes Mick. “It’s very distinctive. The water gets what can look like an oil slick on the surface, and it goes turquoise in higher concentrations at different times of year.

“There’s thousands of different types of algae but blue-green algae can be opaque on the surface. It stinks. It’s quite discernable.”

Incidents of blue-green algae blooms or scums can be reported to the Environment Agency incident hotline on 0800 80 70 60.