Some mysteriously murky water in the Beaverhead River below the Clark Canyon Dam has led to many bad fishing days this year and has left officials confused. After investigating the water this week Montana Fish, Wildlife and Parks Fisheries Biologist Matt Jaeger said the turbid waters began when some unusually cool temperatures upended the water levels this summer.

"With all of this sun, all of this phosphorous got thrown throughout the whole reservoir in the middle of summer when ordinarily it wouldn't have," said Jaeger. "And it's important that it happened in the middle of summer because you have have warm temperatures and a lot of daylight or sun that allows of course primary productivity and photosynthesis and all of those things and caused all these algal blooms."

Jaeger said that the algae bloom explains about half of the clouded water, but there are still mysteries to be solved.

"The second part looks like a suspended sediment, it's an organic material, so not the algae," said Jaeger. "It's somehow making it's way to the outlet and that's the part we're not as sure about why it all came into suspension. It was probably again related to the reservoir just ratifying and mixing."

Jaeger said FWP will continue to analyze the phenomena next year and says the water levels usually don’t mix until fall; he described this year’s event as “very unusual.”