There was outrage yesterday after a photograph emerged which showed two men pushing buggies across Cardiff’s River Taff.
At least one child appears to be in one of the pushchairs, which were being pushed across the river at Blackweir, near the Blackweir Bridge.
Penarth Coastguard tweeted the picture yesterday and warned: “Blackweir is a dangerous place to swim, but this is just reckless and dangerous.”
It said being swept over Blackweir was like “being dumped by a constant barrage of pumping waves with the churning water forcing you down”.
“It only takes ankle deep water to knock you off your feet. It only takes 60 seconds to drown. Fast flowing water hides dangers such as rocks, holes, debris and fallen trees trapping the swimmer,” the coastguard said.
Sergeant Adrian Snook, of South Wales Police, said: “We can understand why people are attracted to the river in this hot weather, but we cannot emphasise enough just how dangerous this can be because of the water temperature, underwater hazards and undercurrents.
“We would advise anyone wishing to cool off this summer to visit one of the many safe and supervised swimming pools in Cardiff.”
Natural Resources Wales, which manages rivers and operates a fish path at Blackweir, said weirs could be “extremely dangerous”.
Although the water may appear calm, it can have strong currents making it dangerous to paddle, swim or boat, a spokesman said.
The photograph was posted on the Facebook page “Spotted Cardiff” on Sunday night, prompting almost 200 comments – most of which were shocked at the image.
One person wrote: “Not only reckless but also a way of getting those kids absolutely petrified of water. Disgusting!”