Cherry Creek Spillway

[Brian]

Not sure how I ended up thinking about this tonight...

There's a canal/ditch in the ground just NE of the Cherry Creek Dam. I've driven over it a hundred times but never really paid attention to it. The walking trail right next to it says "Cherry Creek Spillway Trail". I'm confused though as most spillways I've ever seen are connected to a morning glory or something and are usually dumping water out on the opposite side of the dam. The "normal" spillway that leads North out to Cherry Creek is actually fairly small, so I'm assuming this 2nd spillway is mainly for flood / overflow protection. So is it just a natural grading thing, where the water gets so high in the park that it eventually just flows over the campground into this spillway? CC Reservoir doesn't have an open morning glory does it?

Anyway, just curious if anyone knows anymore about this. I've been in the park a number of times, but usually not on this end, and it just looked odd to see this large area on the map that I wasn't aware of.

It was interesting to read the controversy around the "probable" chance that the dam could fail one way or the other at some point.

[brutal]

Ban Cherry Creek Reservoir! It looks like a GUN!

Be interesting to see that on a topo.

[Ridge]

Might be an old, out of use spillway. Sure as hell know that if the reservoir overflows into that, Parker and Iliff is going to be worthless.

[BPTactical]

It is an emergency overflow. Believe it or not, the little muddy brook known as Cherry Creek services a huge drainage basin, as far down as Castlewood Canyon which had a dam in it up till 1933 when it failed. The ensuing flood hit Denver with about a 15' crest.
If enough rain came down for a long enough period near Parker/Franktown or basically north of Palmer Divide all of that drainage flows into Cherry Creek.
It serves a purpose.

[speedysst]

Not only that but its like a half pipe on its side and I rode my bmx bike on it many times years ago.

[8Ring]

I ride my bicycle all around the Reservoir. I doubt that the spillway NE of the Reservoir is meant for overflow. There's about a 50 foot or more elevation gain between the Reservoir and the Parker Road / I-225 intersection northeast of the park. So by the time the NE spillway could be useful, the water level would inundate the entire park, including the shooting range, back up over Arapahoe Road, and flood the golf course where John Elway plays.

My theory is that the spillway is intended to gather surface water from that part of Aurora and act as a detention pond / drainage ditch into the Reservoir. That assumes there is some sort of underground pipe that will take it under Parker Road and into the Reservoir.

Your guess is as good as mine.

Chris

[BPTactical]

Mine is not a guess. I worked at both Cherry Creek and Chatfield for about 5 years in park maintenance. Our crews put in every picnic table in both parks.
The reservoir would fill to capacity in a major event, flooding almost the entire park before the emergency overflow would come into play.
Both Chatfield and CCreek, even with periods of high water are only at approximately 30-40% capacity. Their flood capacities are enormous.
All of the facilities within the parks are expendable in a major flood event.

[Brian]

Wow, interesting. There are some interesting pictures out there from the 1933 flood too. It is impressive to think of little old muddy cherry creek causing that much damage.

[Big E3]

The spillway or gorge as we called it in the early 70's, is an over flow bypass. It is there to divert water from over flowing Cherry Creek reservoir and dump it into Toll Gate Creek in Aurora. From there the water would flow to Sand Creek and on into the Platte down river below Denver. Cherry Creek reservoir was designed by the Army Corp of Engineers to protect Denver from a flooding Cherry Creek. Today it would be unfortunate for Aurora, but way back in the day not much was near Toll Gate. Even as late as the 70's Chamber Road was dirt south of 6th Ave and ended at the gorge. The gorge was a great place for ditching high school and drinking beer, don't ask how I know.

[Alpha2]

Did you spot BP in those 1933 pics? He was a bit younger then...