This is the dramatic moment a dozy truck driver knocks over a high-pressure hydrant in China.

The lorry had been delivering a large metal frame in Shanghai on June 7 and was attempting to reverse into a narrow site entrance.

Dashcam footage from another vehicle shows the massive truck manoeuvring back and forth as the driver tried to align properly.

As he slowly pulled forward to gain more turning space, he failed to notice a construction worker desperately signalling for him to stop.

Moments later, the truck flattened a fire hydrant, sending a towering column of pressurised water 50ft into the air, soaking nearby pedestrians and cars.

Local media reported that the street was quickly flooded until police and city workers arrived to shut off the water supply.