A pipeline carrying deadly sour natural gas ruptured in Turner Valley in southern Alberta on Thursday, prompting the evacuation of some of the town's 2,100 residents, the Alberta Energy Regulator said.

 

The regulator said it is working with pipeline owner Legacy Oil and Gas Inc and the local government of Turner Valley, about 60 kilometers (37 miles) southwest of Calgary, to respond to the leak. The gas contains 1 percent hydrogen sulfide.

 

While no injuries have been reported due to the leak, hydrogen sulfide can cause serious injury or even death at levels as small as 100 parts per million. In smaller doses, it will cause irritation to eyes, nose and throat.

 

Turner Valley and many other municipalities in southern Alberta, including the city of Calgary, had already declared states of emergency on Thursday as heavy rains swelled rivers and streams and forced the closure of the TransCanada Highway, the country's main east-west route, near Canmore, 100 kilometers west of Calgary.

 

Legacy Oil and Gas said in a statement the leak had been caused by impacts from trees and other debris on a flow line in rising floodwater. The line is attached to its natural gas well, Royalite 19, in the Turner Valley.

 

The company said it was in the process of shutting down the line at the time due to the flooding.