It happened last week and Sask Environment is letting us know that it appears to be a naturally occurring situation that has caused fish to die in the Moose Jaw River.
Several dozen fish were found dead behind the old hospital site last week and the Ministry of Environment is telling us low oxygen in the water is to blame.
Matt Tyree is a Fisheries unit manager and says they've had several calls from small water systems around the province, saying the lack of oxygen in the water is caused by the increased temperature this past July and no rain.
"Then other factors play into it as well. When you have extended warm periods like have, algae and vegetation start to grow at a much more rapid pace. Particular during the night, when that vegetation is no longer photosynthesizing it actually helps to further drop the dissolved oxygen levels in those systems."
Tyree stresses that there is no danger to the public and that this is just part of nature.
"(Fish dying like this) is a fairly natural process and it does happen every year. Maybe not to the extent that we are seeing this year given the conditions that we've had. But it does occur naturally across the province."
White sucker fish are most susceptible to the low oxygen levels and from pictures that Tyree has reviewed, that appears to be the case in Moose Jaw. He added that northern pike can be impacted as well.