Watershed Council: The game of flows is in the Eagle River | VailDaily.com

Watershed Council: The game of flows is in the Eagle River

Our 126% of average snowpack has local boaters practically vibrating with excitement for what will most likely be an epic whitewater season.

This is the best snowpack we have had since 2014, when streamflows peaked at an admirable 5,860 cubic feet per second at the Gypsum gauge. So whitewater enthusiasts could be in for a treat.

Emphasis on the “could be.” You just never know.

Case in point: The snow year and following stream flows of 2010. The snowpack hovered in the 80th percentile — in other words well below average — until a series of late snow storms hit. The storms were followed by a sudden warming that melted all of the winter’s snow quickly. Flooding was experienced at both ends of the valley and flows were so high that the GoPro Mountain Games had to cancel the rafting and kayaking competitions due to safety concerns.

The speed at which temperatures increase has a big impact on streamflows. Will the temperatures creep up and cause a slow, extended snowmelt? Or will temperatures suddenly go high causing a quick, but short snowmelt?

Slow and stretched out means that the runoff has a chance to infiltrate soils, be soaked up by vegetation, and flow downstream, all of which helps to avoid flooding — and it also means you get to play in the waves for a lot longer. The slower melt also allows for the natural cycles that support healthy riparian habitats.

For example, the rate at which cottonwood seeds set and put down roots generally keeps pace with the receding water levels. As the groundwater drops lower and lower, the roots grow deeper and deeper. If this process is too fast, the cottonwood sprouts cannot keep up and won’t survive that year.

Flooding, of course, has its own role. Although destructive for our built environment, the river naturally floods from time to time. For example, naturally deposited sediment that creates sandbars and islands get scoured and redeposited during a natural flooding cycle. This, too, is critical for a healthy habitat.

Unfortunately, with climate change we can expect to see a couple of negative impacts to spring runoff: less snow over the winter leading to mediocre spring runoffs, and short springs with sudden warmups that cause a rapid melt of the snowpack. Neither of which allow our rivers to recharge during the hottest summer months.

Both hydrologists and soil scientists are also thinking about the soils surrounding our streams. A lot of these soils haven’t seen much water in a number of years. There is a pretty big question mark on how these soils will react to a large influx of water. Are they so dry that they will soak up large amounts of water before it ever reaches our streams?

The biggest influence on how much water the soils will soak up is how dry they were in the fall before the snow fell. In Eagle County our soil moistures were, for the most part, 50-90% of average before the winter snows began to accumulate. In other words, following a drought, a good snowpack doesn’t necessarily mean that we will experience an exciting whitewater season. However, the value to our environment and natural habitat is priceless.

How will this play out? We won’t know for at least a few more weeks. While you wait, you can put your predictive skills to work and maybe come out of it with a prize for your efforts.

Eagle River Watershed Council is running the Peak Flow Prediction Contest the month of April where you take a guess at the date, time and flow of the peak runoff at the Gypsum gauge. The closest guess will win a raft from Rocky Mountain Raft, while the following five best guesses will win prizes from Centennial Canoe Outfitters, Vail Resorts Epic Promise, Sea to Summit, Orvis, and REI. Learn more and enter at erwc.org for just $15 for one guess or $40 for 3. Just do it by April 30t at midnight.

Holly Loff is the Executive Director for Eagle River Watershed Council. The Watershed Council has a mission to advocate for the health and conservation of the Upper Colorado and Eagle River basins through research, education, and projects. Contact the Watershed Council at (970) 827-5406 or visit http://www.erwc.org.