South Platte River: High flows this spring are helping with recovery

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From The Denver Post (Karl Licis):

n a year of abundant rainfall on the heels of a decent winter snowpack, river flows up and down the South Platte have been above the long-term average. Below brimful Cheesman Reservoir, the volume approached 800 cubic feet per second the past few weeks, but has been gradually receding. The higher flows are expected to benefit the river and its fishery, and some of their effects may already be evident…

…after the Schoonover and Hayman wildfires in 2002. Rain in the burned areas produced a series of flash floods and caused extensive erosion. Untold tons of sand, gravel and other sediment were washed into the river. Massive deposits of unstable gravel settled out along the river bottom, filling in many of the pools, riffles and deep runs that gave the river its character and were vital to the fishery. Both the river’s productivity and fishing appeal were greatly diminished, but at last the South Platte has begun to heal itself…

Though the process may be slow, higher flows, including the recent surge, continue to scour sediment deposits from the river bottom. “We have the evidence that they’ve helped push a lot of sediment downstream from Schoon-over (Gulch, in Cheesman Canyon) downstream to about Trumbull,” Spohn said. “The higher flows have benefited the river above Deckers, but below Trumbull, where the river loses some gradient, we’re still seeing sediment depositing.”[…]

Elevenmile Canyon on Tuesday was flowing around 175 cubic feet per second…Flows in the “dream stream” segment of the South Platte had come down to about 146 cfs on Tuesday…[the Fryingpan] River…has been flowing around 220 cfs…[the] Blue River below Dillon Dam has been flowing around 700 cfs and continues to drop…[the] Poudre River…has dropped and cleared, and was flowing at 750 cfs at the canyon mouth on Tuesday.

More Coyote Gulch coverage here.

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