Sometimes stuff just breaks.

That’s the assessment from the city of Springfield, which shut down Fifth Street in downtown last week after a 10inch water main burst, heaving the street that cracked open from curb to curb, with water shooting upward through the fault like an upside-down waterfall.

“This was a big one,” says Tom Skelly, water division manager for City Water, Light and Power.

The main had some corrosion and was more than a century old, but that isn’t necessarily a big deal, Skelly said. The city has 17 miles of water mains that are at least 100 years old and working perfectly fine. Officials have speculated that a change in water temperature might have a bearing, but that’s only a guess, Skelly said.

“We don’t know why it broke,” he said.

“We’ll never be able to figure it out.”

The city figures it will cost $20,000 to fix the street and another $11,000 to repair the main.