This body of water does not typically exist.
The worst of this insane tropical storm is happening parts north – Boulder, Lyons and environs. There geographic verticality is guiding once-in-a-generation (rarer yet, actually) rains into tight channels that are shooting stream flow numbers into the 10x-50x ranges and doubling, tripling, quadrupling typical gauge height (this USGS site has the details). A few highlights:
- Cherry Creek in Denver has risen from a 3.2 feet guage height to a peak of 8 feet, down to about 7 feet at 5 p.m. So the creek path path is submerged. Flow shot from an average for the date of about 10 cubic feet per second to probably 1,800 cfs at the peak, down to about 1,000 cfs at about 5 p.m.
- The South Platte at 64th ave is flowing at 2,890 cfs at 5 p.m.; mean is 196 for Sept 12.
- Boulder creek is running at 8.5 feet rather than five feet average at North 75th Street. Its 5,200 cfs flow is more than 50 times the average of about 70 cfs. This is, apparently twice the all-time high.
In our own little backyard, I tallied abut 8 inches of rain since yesterday, 3 of which fell in a two-hour span this afternoon. After that pulse, I headed out on a bike with cell-phone and video camera (will post at some point). Here’s what I saw.
(note that at 7:20 p.m. today I stopped back by the floodplain and water levels were down about three feet from what I photographed, so I assume the dam can handle the 2 or so additional inches we’re expecting still tonight).
(Note 2: My thoughts are with friends in Lyons and Boulder whose homes are underwater or partially entombed in rocky mud.)
Detritus in the 11th Avenue dam in Lowry at about 1:40 p.m. on Thursday, Sept. 12, 2013. This is typically a wetland, more recently a dryland. The detritus is blocking a path I typically jog. Much of it is cattail stalks but augmented by litter fools have thrown out their car windows far and wide.
A petite Grand Canyon where the water behind the dam breached the crusher-fine path. Looking north parallel to Uinta Way.
Water level was about 62.3 feet atop this spillway and, by extension, within the 11th Avenue dam of Westerly Creek as of about 1:45 p.m. on Sept. 12. Typically the water level is 15 feet lower. I never imagined seeing it wet, much less in 5 inches of water.
My feet atop the spillway. Crocs save the day.
View to the northeast form atop the 11th Avenue dam spillway. Dude in the center soon shooed me out of the spillway, for obvious reasons. They're trying to clear the pipe intake below 11th Avenue here. Westerly Creek north of 11th is typically a couple of feet wide with very little flow this time of year. Water flows over 11th Avenue here
View of the wetland behind the 11th Avenue dam from atop the spillway. Call it Lake Lowry.
A house floods just east of Westerly Creek north of 11th Avenue. The entire neighborhood was later evacuated. Our house in Lowry is about 20 feet higher than theirs.
If it weren't insane, it would be beautiful.
See previous caption. I run these stairs on occasion - the water stops at the rails of the midpoint.
View north from closer to the spike-like sundial feature. Bonfils Blood Center is to the right. The recycled-water sprinkler covers were a common type of detritus on my ride.
When crayfish are hanging out on the sidewalk, you know you've had a bit of rain. Machebeuf High School in the background.
Entering the Great Lawn. Water's eight inches deep ahead (that's a jogging path)
The water's high point near the Lowry Great Lawn playground, demarcated by cattail stalks and leaves.
Close-up of a bridge near the Lowry Great Lawn playground. The larger stick is the work of beavers upstream.
Westerly Creek at the Lowry Great Lawn. Typically this is a stony trickle this time of year.
Another Great Lawn sidewalk
This little fellow had a rough day.
A most appropriate warning
Another photo of my Croc'd feet, in case you missed the first one (on the bridge about which I had just been forewarned).
A noble puggle inspects the carnage of Lake Lowry a couple of hours later (here at about 8th Avenue and Uinta Way, looking north). The water was down a couple of feet as the rain and let up.