Staff and patients of the Reed Medical Group, 404 Maine St., were evacuated outside their building Friday morning after a nearby gas leak. Reed Medical Group decided to close for the day.

A significant gas line break Friday morning in North Lawrence sent emergency crews scrambling to multiple parts of the city, forced train traffic in the city to be shut down and prompted a medical office to close for the day.

The four-inch gas line rupture was a direct result of the ongoing construction project at Second and Locust streets and caused the distinct smell in natural gas to waft over not only the immediate area of the leak, but also as far as a mile away.

Curt Floerchinger, Black Hills Energy spokesman for Kansas, said a construction worker caused the leak by hitting the line with a backhoe. It happened in an area alongside the Union Pacific train tracks where crews are building a temporary stockpile area for the road construction project, the city said.

Trains on the Union Pacific track were stopped in both directions until Black Hills Energy crews could stop the flow of natural gas from the ruptured line.

Gas was shut off to about 20 customers in an adjacent mobile home park while crews worked to fix the line, Floerchinger said. The problem was fixed by Friday evening.

According to Lawrence-Douglas County Fire Medical officials, there were numerous calls about the rotten eggs-like odor from all over the city.

“I was down there and it was making me nauseous,” Floerchinger said.

Emergency crews responded to both sides of the train tracks near where the leak occurred and to areas south of the Kansas River, like the Pinckney neighborhood, where paramedics responded to at least four people who reported they were overcome by the natural gas odor. A fire official said none of the patients required hospitalization.

Firefighters evaluated Bert Nash, Lawrence Memorial Hospital and the Reed Medical Group, but determined natural gas levels were safe for people to remain in those buildings.

The Reed Medical Group building, 404 Maine, was evacuated and several people complained of feeling ill after being exposed to the natural gas odor. Employees at the building were sent home for the day and patients with appointments were turned away.

“The fumes are overcoming; a lot of people have dizziness and headaches,” said Barbara Walters, an employee of the office. “Just to be on the safe side and for everyone’s health, we’re just going ahead and shutting down.”

Floerchinger said the odor was never a major risk to anyone. He said natural gas itself doesn’t smell and that people smelled a potent chemical that’s added to the gas to alert people of leaks.