Our #1 question and concern from this winter – What’s going on with the Bighorn and what are the flows going to be like this year??
As many of you know the last two years were record water years for the Bighorn and impacted the wade fishing windows, hatches, water clarity, and water temperatures just to name a few.
The 2017 & 2018 water situations had less to do with the winter snow pack and more to do with nonstop, record spring storms that pounded the water shed well into June. While we remain frustrated with water managers that much more can be done to help, it’s Mother Nature that went out of control in late spring causing record outflows from the lake in May and June.
To help frame the amount of water we are talking about, the storms in April/May of 2017 increased the snow pack equivalent to 21 inches vs. a 13 inch average! This translated into 270% higher water volume flowing through the system April-July vs avg. 2018 was largely the same
The late season snow accumulations were not accounted for in the Bureau’s water release/Lake level schedule. The ‘oh shit’ button was pushed and we had 6 weeks of very high water, with about another month or so of ‘higher’ water.
High water on the Bighorn (over 8K CFS) is pulled from a combination of bottom release and spill over gate water. If you watch the USGS graphs during this increase 7k – 8k +, you will notice the river temp jumps about 10 degrees. This is where the top level lake water comes into play.
So, when the Bighorn temps warm up, it takes a lonnnnggggg time for them to cool down (December 2018 is when they did). 60+ degree water temps in June leading into July bumped our main summer hatches about a month ahead of schedule. The water got warmer, more vegetation grew and by the end of August/early September, it was not looking good.
Fast forward to mid-winter 2019 and the river looks great. The cold, clear lake water is back at the bottom where the release is being pulled from. Our snowpack is right at average (THIS IS GOOD!) and so far we are looking forward to a somewhat normal Spring. Lake levels are right at about 80%, so there is some decent storage space. It will be another month or so until we can give you an accurate prediction of what’s to come, but we are looking good so far!