Morning Joyce,
Sorry for the delay in responding, my keyboard got wet and I couldn't do
a thing with it. A friend gave me a replacement last evening. It was
interesting to see our area and some of the damage on the national news and
cable news channels. We had slight drizzle most of yesterday along with only
a few showers. I gave me a chance to survey damage and start planning
repairs.
Arroyos are what you would call a draw of sorts. We have canyons, draws
and Arroyo's. Canyons and draws are self explanatory, so here is what we
call an arroyo. If you have seen the deep erosion cuts on the sides of
hills, overpasses and dirt piles, that is the start of an arroyo. Normally
they are at the mouths of canyons and draws where they open to and cross the
desert. Where a draw or canyon will have a vertical rise in terrain on
either side, (hills, ridges and such), that form it and control/ direct the
drainage. An Arroyo will be a cut in the desert floor along the easiest path
it can find. Most take years to make due to the "Normal" limited rainfall
and range from 5 to 75 feet wide and from 6 to 40 feet deep, sort of mini
grand canyons.
The bad thing about them is that due to the shape, (a deep, normally
narrow "U"), when we have the heavy rains as in the past few days, they fill
and "Roar" like nothing you have never seen. Each Arroyo starts as a draw or
canyon and is fed by many, (sometimes hundreds) of smaller draws, drainages
and arroyos. In doing this they widen, get deeper, change direction due to
debris clogging them up and generally are totally unpredictable, what makes
them so dangerous. Environmental changes in the landscape by man, oil field
roads, well locations, "Urban Sprawl" and such can make a minor change in
the flow of the water and redirect or start a whole new system.
It is estimated that the wall of water that came down "Dark Canyon" was
moving in excess of 60 MPH and was over 23' tall. On the west side of
Carlsbad where it enters the town they have a new "Monument" setting close t
o one of the roads. A friend of mine described it to me like this, about 30'
west of one of the low water crossing is a "New Bolder", it is about 16'
tall and almost 12' wide, (the way it is setting now) and is estimated to
weigh over 30 tons. It was moved by the flood waters an estimated 9 miles
down the draw by the flood waters. They suspect that one similar to it is
what has damaged a bridge that crosses "Rocky Arroyo" north of town. Boyd
drive, (another low water crossing road) has boulders the size of VW's
littering it. They estimate that it will take about 4 to 6 weeks to clear
all the rocks and debris from the flood.
Sorry this went so long, but it is interesting for me to try to explain
something I have lived with all my life to friends all around the world.
Have a safe one folks, my work is cut out for me today. And thank you all
for your concern, well wishes and prayers.
Jimi
For a South Dakotan, is an arroyo what we, back in the midwest, call a
"draw", a little dry creek bed at the bottom of a gulley? Inquiring minds
want to know. I am sorry for all that water being wasted on you Jimmy..and
my prayers are with you. Could you package some and send to us here in
drought stricken Utah> Joyce
