River Cam runs bright blue and baffles onlookers as environment inspectors mount probe
Locals were left baffled after a popular river in Cambridge turned bright blue this week.
Aerial images – which saw patches of blue running along the edge of the river by Jesus Green and Midsummer Common, near Victoria Avenue – were shared online, with one baffled resident questioning: “Why is the River Cam bright blue?”
One onlooker said they noticed the blue colour start to emerge at around 2pm on Friday, May 3. They said: “It looked like something blue was leaking out of the bank near the Lido on Jesus Green.” Another person said: “It’s a pollution incident that needs reporting to the Environment Agency.”
The lido was recently given a fresh lick of paint ahead of reopening for the year on Saturday, May 4. A spokesperson for the Environment Agency said: “The Environment Agency is aware of reports of a blue discharge in the River Cam. Our officers have attended the site and believe they have found the source.”
“They are working with the site owner to understand what has happened, its potential impacts and to provide guidance to prevent reoccurring events. We are very grateful to members of the public that reported this incident. If you spot a pollution please report it to us on 0800 807060.”
Onlookers were left baffled by the river turning blue
A spokesperson for GLL, which runs Jesus Green Lido, said: “Following reports of a temporary blue residue in the river near the pool on Friday afternoon, we investigated the cause. While not coming from the pool itself, we are unable to determine the source. It is possibly coming from a storm drain following Friday’s heavy rain.”
“The incident lasted for about 30 minutes. An Environment Agency Officer and a Council Officer attended but no action was deemed necessary. As a precaution a drain survey will follow. Jesus Green Lido remains open.”
The popular river, which is the main river flowing through Cambridge, has previosuly been reported to have been increasingly polluted from sewage discharges and phosphates, and nitrates from farmland. It has been enjoyed by swimmers for centuries, including historical figures like Lord Byron, Charles Darwin, Virginia Woolf and Roger Deakin.
The Mirror has contacted The Environment Agency, Cambridge City Council and the Cam Conservancy for an update.