A train needing mechanical repairs at Sydney’s Town Hall station has caused chaos, sparking long delays across the city – even stretching into the evening peak hour commute, more than 12 hours after the initial fault.

The train on the T1 North Shore Line needed mechanical repairs at Town Hall early on Friday morning, stopping trains from travelling between the CBD and North Sydney. At 6pm, delays were still continuing on multiple lines, with Sydney Trains telling passengers to allow extra travel time.

We can understand the frustration from today's delays and disruptions. We would like to thank your continued patience and understanding on the issue. Please rest assure that crews are continuing to work on frequency of service to get everyone home tonight. pic.twitter.com/8v5vv3bD5a — T1 Sydney Trains (@T1SydneyTrains) August 23, 2019

We can understand the frustration from today's delays and disruptions. We would like to thank your continued patience and understanding on the issue. Please rest assure that crews are continuing to work on frequency of service to get everyone home tonight. pic.twitter.com/p3h9FHn1Fj — T2 Sydney Trains (@T2SydneyTrains) August 23, 2019

Social media erupted with complaints, with videos showing long lines of commuters waiting for replacement buses.

#sydneytrains I guess I live between Macdonaldtown and Redfern now. Who would like to join me in creating a new society of Mad Max-esque train dwellers pic.twitter.com/raUrQ8LI2I — dusk and dawn child (@mysamurott) August 22, 2019

#sydneytrains No one’s getting on! Trains full four hours after a breakdown. Newcastle intercity turned into an all station pic.twitter.com/2GIRWzJ4Bg — Doon'n'Jen (@doonnjen) August 22, 2019

At Wynyard station earlier, police were on hand to direct the crowds.

“How does one broke down train bring the whole transport to its knees. Thank you for such a wonderful start to our Fridays!” Twitter user Vin R posted.

“No trains running over the bridge right now, the announcer at Wynyard suggested we walk over the Harbour Bridge to North Sydney as the buses were too busy,” user Sam McCosh posted.

Problems began when a train on the North Shore Line needed mechanical repairs at Town Hall about 5.30am after an open train hatch was spotted by the driver.

Sydney Trains chief executive Howard Collins said the hatch was very close to 1,500 volts of direct current power and could have caused days of damage if left unchecked.

“It could have brought all the wiring down in the city ... we could have gotten stuck over the Harbour Bridge,” he told reporters on Friday afternoon.

So everyone has been kicked out of Newtown station, and this is the current line for buses into the city, lol #sydneytrains pic.twitter.com/WB0zqefzt7 — 🍂❄️🐕Patrick Lenton🌚🍁🌬 (@PatrickLenton) August 22, 2019

It’s not the breakdown itself that is infuriating because I get it - things break down. The infuriating thing is that every time something breaks down, it’s like it’s an unprecedented and isolated event that #sydneytrains hasn’t factored in a contingency plan for. GET 👏🏻 GOOD — Jess Davis (@jess_a_davis) August 22, 2019

Just (literally) chilling on the platform for all the (cancelled) trains. #sydneytrains pic.twitter.com/ClDd4nPf1R — Annie (@atmokineticist) August 22, 2019

Collins apologised for the widespread delays that continued throughout the day but believed his team made the right call in stopping the train.

Early signs pointed to wind or a tree branch hitting the train causing the hatch to open. In order to fix the hatch, power to the line had to be switched off – which involved sending workers down tunnels to pull isolation switches.

Collins revealed those switches were put in place in the 1920s or 30s and were “almost Frankenstein in their look”.

“It is a failure of the way our system is built that one train can stop the entire network,” he said. “We’re working through that, the investment we’re seeing now is starting to isolate these lines.”

Commuters reported being stuck on immobile trains between stations and Uber prices surged in some locations as travellers looked for alternative means of transport.

In a statement on Friday afternoon a spokesperson for Sydney trains said services were “recovering”, but would not run to timetable.