First it was Ada County that declared an emergency disaster due to flooding, followed a few days later by the city of Eagle and now Canyon County Commissioners have voted to declare a disaster emergency for flooding and possible emergency evacuations due to a rise in river flows.

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According to the Idaho Press Tribune, Commissioner Tom Dale said “the emergency declaration does not come with county funding, but instead puts the county in position to potentially obtain aid from state and federal sources”.

Increasing flows on the Boise River have already forced the evacuation of dozens who were renting sites at the Caldwell Campground and RV Park. Those people have been temporarily moved to Canyon County Fairgrounds.

The Boise river, which just last week was at over 8600cfs has decreased to just under 8000cfs over the past few day, however there is a fear of increasing flows again due to an incoming storm this weekend hydrologists say it’s likely to rise again in coming days.

According to the US Bureau of Reclamation, Lake Lowell in Canyon County is already at 93% of capacity, Anderson Ranch was 85% full, Arrowrock was 47% full and, Lucky Peak was at 56%

Here’s what’s a little scary…. The Army Corps of Engineers and Bureau of Reclamation say that more than almost 2 million acre-feet of water is still stored in the mountain snow pack that funnel water into the three reservoirs upstream of the Boise River.

Those three reservoirs together only have about 320,000 acre-feet of space available for the 2 million acre feet that will eventually need to flow from the mountain snow melt. (Let's pause while you do the math and let that sink in for a moment)

What does that mean other than there isn’t enough room in all the reservoirs for all the incoming water…It means water managers will need to continue increasing the water released in higher flows to make room for the snow melt expected from the mountains.

According to the most recent Idaho Snow Survey, South Idaho snow pack in the Bogus Basin region is currently at 142% and still growing, with more snow expected this weekend. Last year at this same time, the snow pack was only at 109% above normal