Pedestrians, cyclists and motorists had to dodge torrents of fast-moving water which gushed through the city centre, flooding streets and walkways yesterday.
There were also bursts in the south side and east end of the city, causing travel chaos and loss of supplies for homes and businesses.
Scottish Water, which received calls from more than 3000 concerned residents, said the problem began after the central system for regulating water pressure malfunctioned early yesterday morning. It has now launched an investigation.
A surge damaged valves, breaking pipes and sending water cascading onto streets affecting streets as far apart as Possilpark to Cowcaddens Road and New City Road in the city centre to Cathcart and Duke Street in Dennistoun.
Cowcaddens Road, near the junction with Hope Street, saw a new attraction - a 30ft high jet of water.
The pedestrian underpass next to Cowcaddens Subway station was impassable, unless people had access to a boat, after it became six foot deep.
Strathclyde Partnership for Transport said the station and subway services were unaffected.
Around 600 students and 90 staff had to be evacuated from Glasgow Kelvin College after flood water from another burst main at New City Road rushed towards the front of the building at around 10am.
It will remain closed to students today for safety reasons.
Water supplies at city primary schools and nurseries were also affected and pupils from St Anne's Primary School, near Gallowgate, were sent home for the day.
St Aloysius College in Garnethill was also left with limited water. The institution is continuing to monitor the situation.
Burst mains caused water tanks to run low at a school and two nurseries in the east end area.
Station Commander Scott McFarlane, incident commander, praised the efforts of his crews at Glasgow Kelvin College.
Scottish Water has recently completed a £3.5 million pipe network upgrade in Glasgow City Centre with more work planned as part of a wider five-year £250m project.
He said: "We are investigating the cause of the issue with our pressure management system and will work to identify how it can be avoided in future.
"We apologise for any inconvenience as a result of these burst water mains and we want to reassure customers that we are working hard to restore supplies as soon as possible."