Walking around Regina's Wascana Creek can be a tranquil, meditative experience — until an offensive odour wafts into your nostrils. For several weeks a potent smell has been coming from parts of the creek — which runs out of Wascana Lake — and the water has been discoloured. The smell and colour are being caused by a buildup of organic matter, according to Kurtis Doney, director of water, waste and environment for the City of Regina.