"With the warmer weather, everything is melting," she said. "The amber, brownish colour is caused by organic material in the water. This happens every year."
An accompanying smell, resulting from decomposing organic material trapping hydrogen sulfide under the ice, is also common in the spring, Sugden said.
She noted that, north of Airdrie, Nose Creek does flow through agricultural land and any manure on that land may also end up in the water.
"It's a natural area, so everything surrounding it could end up in Nose Creek," she said.
Water quality at Nose Creek is always a concern for the City, which Sugden said constantly monitors the creek.
"We do regular testing of the creek, so we're aware of levels," she said. "We tend to notice when there is an increase in a certain reading that we're looking at."
Once fresh water starts flowing into the creek, it will return to its normal colour, Sugden said, although it is hard to predict when that will happen. So far this year, the City has not had calls from resident about the colour of the creek, although residents will usually contact them with concerns about the smell.
