Decades of neglect in Detroit's critical infrastructure has culminated in a massive day-long blackout which left much of the city unable to function.

The blackout, which hit Detroit’s municipal power grid, commenced on a Tuesday morning and affected over 900 locations. Outages continued until at least the late afternoon in roughly two-thirds of afflicted areas.

Investigators have since determined that the blackout was caused by a “major cable failure” at the city-owned Mistersky Power Generation Plant at around 10:30 a.m. local time, which resulted in the shut down of the entire municipal grid.

When the Public Lighting Department attempted to reconnect customers by means of another circuit a breaker on the new circuit malfunctioned, and this in turn caused a system-wide shutdown depriving all customers on the city grid of power.

The blackout threatened to cause chaos and panic in the city, with an estimated 740 traffic signals left inoperable, including all those situated in Detroit’s downtown area.

Public facilities were particularly hard hit as a result of their dependence on the city grid, including schools, hospitals, fire stations, incarceration facilities and courts of law.

The city-wide outages also caused major headaches for the Detroit Fire Department, whose personnel spent much of the afternoon rescuing people trapped in the stuck elevators of buildings hit by the blackout.

Detroit Mayor Mike Duggan said neglect of the city’s infrastructure as a result of its economic travails and bankruptcy was a major factor in the blackout.

“Today is another reminder of how much work we still have to do to rebuild this city, and a bankruptcy order doesn’t solve the decades of neglect in our infrastructure,” said Duggan at press conference.

The day-long blackout of one of America’s biggest cities is further evidence of the ailing state of critical infrastructure systems in the United States.

The American Society of Civil Engineers has repeatedly given poor marks to the state of US infrastructure, concluding in a recent report that much of system remains still well below acceptable standards.

“A large portion of the system exhibits significant deterioration. Condition and capacity are of significant concerns with strong risk of failure,” said the report.

US President Barack Obama recently called the state of the nation’s infrastructure “embarrassing” while addressing an audience of CEOs at the Business Roundtable’s headquarters in Washington.