Geology Home Page
Roger Weller, geology instructor
by Richard Miller
Babacomari River, Southeastern Arizona
Almost everyone living in the Sierra Vista area has one time or another
driven over the “San Ignacio Babacomari River,” without ever realizing it.
That’s because where highway 90 goes over the bridge in lower Huachuca City,
the river seems like the ordinary ephemeral stream (dry wash). That is only
because this river that flows year around, disappears under the ground for a
short distance only to reappear above ground 6 miles downriver.
The Babacomari River is a tributary that feeds into the San Pedro River.
The river begins almost exactly on the border of Pima and Cochise County, on
private property known as the “San Ignacio Del Babacomari Land Grant.” The
river is approximately 16.23 miles as a crow flies in length. The headwaters are
at an elevation of approximately 4,683 ft. The river makes its way 16 miles plus
to the San Pedro River, where the mouth of the river is at an elevation of
approximately 3,898 feet.
The springs are supplied year around by an aquifer that is filled by a
basin that stretches from the higher elevations of Elgin to the west, the
north side of the Huachuca Mountains to the south and the south side of
the Mustang Mountains to the North. This basin gathers the water which
feeds the Babacomari springs, these springs are where the Babacomari
The Babacomari Dam when flowing can produce as much as 790
gph, most often during the monsoons and winter rains. This dam closely
balances the use of water to irrigate the fields for livestock and also to
supply the river. Most commonly during the winter and monsoon months
water is plentiful, but during the summer the river can whittle down to
just a trickle in some areas. In the worst case scenario during a bad
drought, the river can even become stagnant.
Photo from Babacomari Ranch Photo by Richard Miller Photo by Richard Miller
Approximately 4.4 miles east from the Babacomari spring, both
the river and the riparian zone disappear. This forms an ephemeral
stream (dry wash); this is what most people see when they drive thru
lower Huachuca City. Just a mere 126 years ago the river was flowing
thru what would currently be lower Huachuca City. On May 3, 1887 a
7.6 earthquake, which its epicenter was in Bavispe Mexico, shook
southern Arizona. This earthquake caused the Babacomari River to go
underground for the next 6 miles, where it then reappears to flow like
nothing ever happened. Changes such as this in the area from this
earthquake were not uncommon, 20 miles away in the town of St.
David, artesian wells sprang up as well as many other geologic changes
along the San Pedro River.
The final 6.3 miles of the river developed into a beautiful
riparian zone full of vegetation as if there was never any diversion of
the river as a result of the earthquake. At the mouth of the river the
amount of water that reaches the San Pedro River, is only a trickle of
its original amount. Of course that should be expected, I think most
people don’t understand the life that even such as small river such as
the Babacomari contributes.
Photo by Richard Miller
I was once talking to “Frank” the Ranch Manager of the
Babacomari Ranch. He said that “the cottonwoods alone drink more
than a foot of water out of the pond a day in the growing season”.
I was blown away when I started multiplying the 12 miles of
cottonwoods alone that this river fed. Not including the deer, birds,
plants, cats, insects, reptiles etc that this little unknown river gives
life too. One question did come to mind, “when the river stopped
flowing from the earthquake for that 6 miles, did the river just go
back down into the aqueduct and where river reappears is just
another spring or did the river actually create another route
was a lot of history that goes along with the
Babacomari River, too much to really sum up, but there was one
specific passage I read on Babacomari Ranch website that drew
me in when I first began my research.
year, Coronado and his army came this way on
their famed but unsuccessful search for the Seven Cities of Cibola
and the ever-elusive El Dorado. Then this ancient land fell back
into the prehistoric silence which had been so unexpectedly
shattered by the coming of the white man and his restless search
for souls and treasure. A hundred and fifty years elapsed before
the black robes of the Jesuit priests were seen in the Babacomari
Valley, with the redoubtable Father Francisco Eusebio Kino
leading the way. This was the year 1692, when Father Kino first
made the acquaintance of Chief Coro at his extensive village of
Quiburi where the Rio Babacomari empties into the San Pedro,
and caused Kino to remark: "it is true that I found them somewhat
less docile than the foregoing people of the West." The next day
he proceeded up the Babacomari to the Cienaga and village at
Basosucan (modernized Huachuca) where he met Chief El Taravilla,
which means "the Prattler." La Cienaga — now the site
(headquarters) of Babacomari Ranch. The name of the village is
still preserved in Huachuca Mountains and Fort Huachuca nearby.
Huachuca was the last village of the people whom the Spaniards
called Pimas Proper, those beyond were Sobaipuris."
I chose this passage from the Babacomari Ranch website in
my closing because I think it really demonstrates how this small,
forgotten river played not only such an important role in the
development of a huge valley geologically. But how important
this river on a daily basis was for the development of mankind,
for who knows how long. So the next time you are going through
lower Huachuca City and you see the sign for the “Hideout,” you
know you are crossing paths with Francisco Coronado and right
down that road is where the indian village “Basosucan” once was.
Links to information