This video – recorded between 1830 and 1900 hours on 3 September 2007 – depicts flooding in the Mojave Desert of the southwestern United States along Koala Road near the desert community of Adelanto in San Bernardino County, California.

The runoff depicted in this video was probably the result of a somewhat high-intensity precipitation event produced by a thunderstorm that occurred some miles (kilometers) away from Koala Road. The runoff may have generated a sheet of water known as ‘overland flow’ which eventually found its way into the nameless channel shown here.

This particular channel flows in a generally northerly direction draining a portion of Baldy Mesa and the sedimentary geomorphic surface known as the Victorville Apron located more than 10 miles (~16 kilometers) to the south of Adelanto. The channel is a tributary to a much larger stream channel called Fremont Wash. Fremont Wash funnels runoff from channels draining the Victorville Apron/Baldy Mesa area as well as east-flowing channels draining the Shadow Mountains located to the northwest of Adelanto. Fremont Wash is a tributary to the allogenic Mojave River – the main stem stream for this part of the Mojave Desert. Fremont Wash flows in a generally northeasterly direction forming a confluence with the Mojave River near the community of Helendale. Helendale is located on old Highway 66 in San Bernardino County, California.

The stream channel shown in this video is just one of thousands of nameless channels in the Mojave Desert in which water flows only when there is sufficient hydrologic input. Though common enough features in desert landscapes around the world, such stream channels may be dry for years or even decades at a time. Streams with such an unprecitable, non-seasonal flow regime are referred to as “ephemeral” streams.

It is common in deserts for the runoff generated by a storm in one area to flow across the desert for great distances (many miles/kilometers) to fill a stream channel in an area where no rain is falling. Such was the case with the runoff shown in this video: No rain was falling in the area where this video was recorded.

TECHNICAL:

Equipment | video function on a Canon PowerShot A630. Camera was hand held (unfortunately).

Editing | Windows Movie Maker.

Duration : 0:3:17


[youtube hRP9k3iJa4E]

Technorati Tags: , , , , , , , ,

Tags: , , , , , , , ,

This entry was posted on Sunday, February 15th, 2009 at 1:42 am and is filed under Mohave County Az. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

17 comments so far

bapyou
 1 

Hello. This is a …
o. This is a reply to your comment from 8 months ago.

I have a new memeory card that is 4GB. I have several of them now.

Also, if you haven’t figured it out by now, to get the best quality video using your Canon A630, be certain that the camera is set on STANDARD video.

February 15th, 2009 at 1:42 am
bapyou
 2 

Of course, desert …
Of course, desert ephemeral flows vary in both space and time; variation with time is the very essence of the term ephemeral. Calculating discharge would vary depending on where along the flowing stream channel you decide to measure.

Hey, thank you again for your comment. I always enjoy engaging in a discussion of topics realted to hydrology and/or geomorphology. There aren’t many persons with whom I can do so.

February 15th, 2009 at 1:42 am
bapyou
 3 

How about this for …
How about this for a crude estimate of discharge on the road at the beginning of the video:

The flow appears to be advancing at a rate of about 1/2 foot per second. Let’s use that for a velocity.

For depth I would guess that it was no more than six inches deep. And the width of flow…let’s say about 10 feet?

So using a cross-sectional area of 5 feet, and a velocity of 0.5 ft/sec inserted into the equation of continuity (Q = AV) that works out to about 2 to 3 cusecs.

February 15th, 2009 at 1:42 am
bapyou
 4 

The big flow shown …
The big flow shown at the beginning of the video went right into a housing development, which made me wonder: What sort of hydrologic/geomorphologic study was or was not done before the development was constructed? Apparently, they’ve built homes right in the path of an ephemeral desert wash. Not a good idea. This runoff event appeared to be relatively modest. What if a real gully-washer of a thunderstorm happened at this location? That housing development could be in for some serious trouble.

February 15th, 2009 at 1:42 am
bapyou
 5 

Hello. Thank you …
o. Thank you for the comment. You’re an aspiring hydrologist? Excellent career choice.

As for the rate of discharge, I couldn’t be certain at all. Obviously, at the begining of the video there is a greater discharge flowing along the road than that which you see in the upper parts of the stream later in the video. Where the stream is very shallow in the “natural” reach shown, the discharge was less than 1 cfs for sure.

February 15th, 2009 at 1:42 am
georellen
 6 

This is really cool …
This is really cool! thanks for posting!
I’m an aspiring hydrologist. I’m curious, what would you guess the rate of discharge is for this event?

February 15th, 2009 at 1:42 am
bapyou
 7 

If such things …
If such things interest you, David, pick up a book on geomorhpology, or, more specifically, fluvial geomorhpology. (The term ‘fluvial’ means stream-related.) Also, there are books that focus specifically on desert geomorhpology. If you’re interested, I can reccommend some titles.

February 15th, 2009 at 1:42 am
bapyou
 8 

Hello David.

” …
o David.

“did you just come upon this event by chance?”

Yes. I was out for a drive in the desert last September when I saw this water flowing down Adelanto Road. What I don’t show in this video is a subdivision, the entrance to which was flooded above the curbing. Seeing that water in the subdivision made me wonder whether the developers of the subdivision had done a proper hydrological study of the site. Of course, this is just speculation on my part.

February 15th, 2009 at 1:42 am
davidsquall351
 9 

thaks for …
thaks for explaining this. i wouldnt know what a ehpemeral stream was.
did you just come upon this event by chance?

February 15th, 2009 at 1:42 am
undercoverjedi
 10 

That looks …
That looks familliar!

February 15th, 2009 at 1:42 am
bulitboy
 11 

If anybody would …
If anybody would like to buy a home in this area with me, let me know, I’m good for a bout a 50,000. loan.

February 15th, 2009 at 1:42 am
bulitboy
 12 

The first shot in …
The first shot in this video is one street west of Muskrat Ave,(my old home) looking south on Koala, it’s a beautiful place, with the best sunsets I’ve ever seen.

February 15th, 2009 at 1:42 am
iPilipino
 13 

wow. How much …
wow. How much memory is in your card?

and like i read that you use Windows Movie Maker, so what do you choose when youre about to save your edited videos on your computer?

February 15th, 2009 at 1:42 am
bapyou
 14 

Hello i. I have to …
o i. I have to tell you that I am not sure what preferences I use! I just shoot a video and upload it. That’s all. I can say that the memory card for my camera fills up pretty quickly; only about 3 or 4 minutes of video max.

February 15th, 2009 at 1:42 am
iPilipino
 15 

Ok Mr. I have a …
Ok Mr. I have a question for you. Well we basically use the same camera yet your video quality is much higher than mine. If you take for example this video, and my “School Lunch Time” video, you will see that my video has way lower video quality. So my question is, what video preferences do you use? Like what preferences do you choose before uploading it on YouTube?

Please help me.

February 15th, 2009 at 1:42 am
bapyou
 16 

Doubtful that there …
Doubtful that there is gold in that sand, Doc. Some body would have found out by now. But, maybe. I didn’t look. Ha ha!

BTW, this location is not all that far from California City where, you told me, you almost bought some land. I can take you up to California City if you like, if and when you come out to CA.

February 15th, 2009 at 1:42 am
bushuraloser
 17 

So get out your pan …
So get out your pan cause I reckon thars gold in that thar sand.

February 15th, 2009 at 1:42 am