Bogley

[stefan]

ice vader wrote:
Somewhere in the story it says they floated 3 miles!!!!

okay, i missed that. so 8 ---> 3. good i think the way i heard the story was a bit exaggerated.

ice vader wrote:
I also was laughing about it being reported as a 100 year storm, which was the same report after some of the storms we had earlier this month.... It looks like we get a 100 year storm about every 4 or 5 years.


okay FIRST, the guy incorrectly reported that it was a ONCE EVERY 100 YEAR (or however he stated it precisely).

but it should be clarified that a N-year storm is not saying that it can only occur once every hundred years, it's a measure of the size of the storm based on the probability that such a storm could occur in any one year. 100 year storm is the same as saying that such a storm has a 1% chance of happening in any given year (inverse of the probability of it occuring). but this doesn't mean that in one hundred years only one such storm will happen. there are a lot of assumptions in this as well. but the point is it should be taken more as a characterization of the size of the storm. more than one can occur within a year, especially if el nino is in effect

i spoke with the hydrologist from escalante. he said that the last time there was such a FLOOD was back in 1987-88 sometime. the hydrologist in escalante put the event there at 20-50 years, but they're still collecting data. i believe this is characterizing the FLOOD, but i am in the process of checking back with him[note that 100 year storm can be different from 100 year flood.]

i asked mr brian_noaaguy about the validity of the 50-100 year storm for the whole of southern utah, which is how i first heard it on the news. it was pretty major across the southern utah and he pointed out that hanksville's record rain of 3.75 inches in 24 hours would characterize that storm as a 500 year event. see the following link for hanksville

http://tinyurl.com/yzzn9r

he also pointed out that other areas of southern utah measured 5.75 inches. nat measured roughly 5+ inches in his cup where we were.

[stefan]

so i snagged this a bit ago from the lake powell water database. you can see how the lake level rose within the time period of the flood. it's current elevation is 3607.96 feet.

the link is Lake Powell Water Database. from here you can access other reservoirs as well.

here's a link to an interesting graph http://graphs.water-data.com/lakepowell/index.php

and here's the table as recorded on oct. 12. one thing you notice is that lake powell rose about 5 feet in one week due to that storm.

[jstheman1]

:2thumbs: :2thumbs: :2thumbs: :2thumbs: :2thumbs:

[stefan]

on the range

[stefan]

great video of flooding in hanksville

http://kutv.com/southernutah/local_story_279183845.html


______________________________________________________


found a couple more shots in escalante taken on oct 6
from the page ... http://www.flickr.com/photos/blownaway/page3/



also here is a short excerpt from the following link (also available in pdf format)

http://tinyurl.com/w2z4w

Upper Colorado River Basin Hydrology

The “ Four Corners” region experienced extraordinary amounts of precipitation during
October 2006. Precipitation events were particularly intense in the vicinity of Lake
Powell. Record-breaking daily flows for the month of October were observed on the San
Juan, Dolores, San Rafael, Fremont/Dirty Devil, Escalante, and Paria Rivers in the first
half of October. The most exceptional of these high flows were the flood flows on the
Fremont/Dirty Devil on October 6 and 7, 2006. The stage (level of the river) of the Dirty
Devil (at the “Dirty Devil above Poison Springs Wash near Hanksville, Utah” surface
water discharge station) increased by more than 15 feet during the flood event. The flow
of the Dirty Devil River during the event is currently undetermined as the stage reached
such levels at which flows are not known. Hydrologists from the United States
Geological Survey are in the process of performing analysis to estimate the peak flow and
total volume from this flood flow event. Also, it should be noted, a second high flow
event occurred on the Dirty Devil River on October 17-18, 2006.

Localized inflow from the Dirty Devil River and other drainages (which outlet into Lake
Powell) resulted in remarkable increases in Lake Powell on October 6, October 7, and
October 8, 2006. Daily increases in the water surface elevation of Lake Powell on these
three days were 1.33 feet, 0.97 feet, and 0.74 feet, respectively. Such daily increases in
Lake Powell are unprecedented in the month of October. Every drainage and arroyo
which outlet into Lake Powell was flowing during this period. Literally hundreds of
waterfalls were observed in the sandstone cliffs which perimeter Lake Powell during and
after these storm events.

Numerous other precipitation events, not only in the Four Corners region but throughout
the Upper Colorado River Basin, in October, resulted in much above average inflow.
Unregulated inflow in October 2006 was 1,018,000 acre-feet or 184 percent of average.
This volume does not include unmeasured localized inflow, however, which could be as
high as 350,000 acre-feet of additional water.
Lake Powell rarely increases in storage during the month of October. However, in
October 2006, Lake Powell increased in storage by 609,000 acre-feet, gaining 6.2 feet
in elevation. The current elevation of Lake Powell ( November 1, 2006) is 3,608.0 feet.
Reservoir storage is currently 12.53 million acre-feet, 52 percent of capacity.
Inflow to Lake Powell has decreased from the very high levels seen in early and mid-
October. Inflow is currently about 11,000 cfs, with the level of Lake Powell holding
nearly steady. Inflow is expected to decrease during November 2006, and the water
surface elevation of Lake Powell will likely decrease during the month as well. Decreases
in the water surface elevation of Lake Powell are projected to continue through the winter
until April 2007, when anticipated snowmelt runoff will cause the water surface level to
increase once more. The projected elevation of Lake Powell on January 1, 2007 is now
about 3,605 feet.

Upper Colorado River Basin Drought

The Upper Colorado River Basin experienced five consecutive years of extreme drought
from September 1999 through September 2004. In the summer of 1999, Lake Powell was
essentially full with reservoir storage at 97 percent of capacity. Inflow volumes for five
consecutive water years were significantly below average. Total unregulated inflow in
water years 2000, 2001, 2002, 2003, and 2004 was 62, 59, 25, 51, and 49 percent of
average, respectively. Lake Powell storage decreased through this five-year period, with
reservoir storage reaching a low of 8.0 million acre-feet (33 percent of capacity) on April
8, 2005.

Hydrologic conditions improved in water year 2005 in the Upper Colorado River Basin .
Lake Powell increased by 2.77 million acre-feet (31 feet in elevation) during water year
2005. Unregulated inflow to Lake Powell in water year 2005 was 105 percent of average.
Unfortunately, in 2006, there was a return to drier condition in the Colorado River Basin.
Unregulated inflow to Lake Powell in water year 2006 was 73 percent of average. Over
the past 7 years (2000 through 2006, inclusive) inflow to Lake Powell has been below
average in all but one year (2005).

Water year 2007 (which began on October 1, 2006) is off to a good start. Precipitation in
the Colorado River Basin in October 2006 was much above average, and Lake Powell
increased by 6.2 feet during the month, in large part due to exceptional precipitation
events in the regions surrounding the lake. Nevertheless, historical records show that it is
common to have periods of above average precipitation and runoff during a protracted
multi-year drought. The drought in the Colorado River Basin may not be over.



also the following excerpt is from http://tinyurl.com/y3s9no. i believe the brian mentioned in this is a uutah member (brian_noaaguy)

METEOROLOGICAL SERVICES DIVISION

Service of the Week: On October 5th and 6th, a strong upper level storm system infused with tropical
moisture moved over the eastern Great Basin, causing very heavy rain and multiple flood events in
Utah. Along with the Grand Junction Colorado office, WFO Salt Lake City prepared the people of Utah
for the event with timely products and excellent personal service. In southern Utah, briefings from
Service Hydrologist Brian McInerney to National Park Service officials in the
days and hours before the storm prompted them to stop issuing backcountry permits well ahead of
time, keeping hikers out of harms way before flooding began. Rainfall of two to three inches was
widespread, with isolated amounts of over five inches reported. Some locations received 50 to 75
percent of their normal annual rainfall in less than 30 hours. Flash flooding occurred in many slot
canyons and normally dry washes, roads were washed out, and rivers flooded; the Dirty Devil River
near Hanksville UT rose from 40 cfs to 14,000 cfs in a matter of four hours.

The pro-active action by WFO SLC was greatly appreciated by the parks. An email received from an
official at Capitol Reef NP stated that the direct communication enabled them to "pre-close impacted
roads before they were damaged, reducing the threats to visitors and park staff alike...". Park
representatives also stated “the communications were very helpful, and vital for the safety of all people
in the park during the rains and subsequent flooding. The advance warning gave our visitor center staff
the opportunity to warn not only park visitors, but those traveling throughout the region about the
anticipated and occurring weather, which resulted in the closure of State Highway 24. Our expectations
of the weather event meant that patrols rangers were especially observant of potential hazards, and
recognized the loss of curbing that indicated the Fremont River was undercutting Highway 24. Thanks
to the National Weather Service hydrology team in Salt Lake City for their accurate and helpful
information! It most definitely prevented potentially tragic incidents at Capitol Reef National Park.”
Also, from Grand Staircase-Escalante National Monument: “I was very impressed with the fact that you
called us and warned of the intensity of the storm that hit us on Thursday Oct 5 and Friday Oct 6. It
was very helpful to be able to tell people that it was not a good idea to be heading down the Hole in the
Rock road etc. Of course some of them did not listen to us and ended up being stranded for several
days, but many people did listen and I think we would have
had many more rescue situations if you had not taken the time and effort to inform us of the potential
that this storm had. I was very impressed with your concern and thoroughness.”
In northern Utah, the WFO briefed Emergency Managers twice on Friday that heavy rain later in the
day may cause debris flows from burn areas. Flash flood warnings were issued as the rain began, and
on Friday evening a debris flow on the Snow Canyon Burn area near Logan caused road damage and
evacuations.

No deaths or injuries were reported during this large scale flood and flash flood event, due at least in
part to the excellent preparation of Emergency and Park officials by WFO Salt Lake City. Excellent
work by all involved in this event!

[stefan]

neat videos from clear creek in the lower escalante

october 6, 2006 ... the day of the flood

[Cirrus2000]

Wow - cool video. Thanks for posting it!

[accadacca]

WOW! That is cool! :popcorn:

[stefan]

okay ... i guess it amazes me that every time i search on the web for the october flood, i continue to find more and more related stuff!!

here are some more photos i just found.


pickup in cottonwood wash, san juan county


pickup in coomb wash, san juan county


poison spider trail


poison spider trail


riverside drive in st. george


just north of Kanab on Highway 89


bullfrog


flooding near lake powell


paria river at tropic or cannonville


hanksville


fremont river


falls, fremont river normally and during flood

[Iceaxe]

I like the Fremont before and during picture. :2thumbs:

[shaggy125]

Iceaxe wrote: I like the Fremont before and during picture. :2thumbs:

Yea, those kids standing on the bank are history by now I'm sure!

[stefan]

i added a new figure to my site, thought i'd also post it here:
i've doctored it a little from the powell wata database

it rained hard from 10/5-6 and was still draining on the 9th, when it started to rain again ...

[hank moon]

marc olivares wrote: great TR Stefan,
i got a camera question, what camera are u using?
and how many of those shots have been Iphoto enhanced?
you got some great color saturation, just want to know how much of it is the mac...lol :wink:

Saturated rock = saturated color!

[stefan]

UPDATE:


so recently i have modified my report on the escalante flood nat smale and i experienced last october during the wild storm that blanketed southern utah. although the old link points to the new location,

the new link to the page is:
Middle Escalante Deluge

__________________

however!! there is a great new addition to the page i believe many will be interested in seeing. the gracious Randi Poer was so very kind and took a number of photos from similar vantage points on her recent trip to neon/chop. i've placed our photos side-by-side for comparison. they are relatively small so most screens will display them, however, if you CLICK on the IMAGE PAIR, they will ZOOM out and you can see more detail. the comparisons are wild.

bottom of page:
Day of the Flood


i am very grateful for the effort she made to take these photos. thank you Randi.

enjoy ...


stefan

[Iceaxe]

Love those side-by-sides. Nice Job of getting them Randi.

:2thumbs: