Wells
take and nothing gives back
to Grand Canyon's ancient aquifer
By Steele Wotkyns
for Headwaters News
There are few places in the West where such a diversity of life occurs in such
stark contrast to its surroundings than at the Grand Canyon's seeps and springs.
But some biologists, geologists, hydrologists, and conservationists are worried
about the continued existence of these biological Gardens of Eden.
Scientists and rare visitors to the lesser-known of these many microcosms bear
witness to the red bud and hop trees, damselflies, crane flies, robber flies,
dance flies, sunflowers, ferns, orchids, cottonwoods — to name just a few
inhabitants.
In a recent photo essay in the Plateau Journal, "Water
From Rock," author Ann Walka notes that one of Grand Canyon's top ecologists,
Larry Stevens, identified more than 30 bird species one morning at a single
spring, and that Canyon springs harbor a density of plants 500 times greater
than the spare upland terrain nearby.
The pure sense of survival is palpable to human visitors to the Canyon's springs,
especially during summer months. Hiking through Indian Garden or up Havasu Canyon
— the latter a sacred place for the Havasupai Tribe — one's whole
being is thankful for the cooling water.
As the mist wisps over your face, one cannot help but be moved by this water's
essential presence here in the surrounding inferno.
Six wells south of Grand Canyon pump a collective 150 million gallons per year from this aquifer.
Below
Grand Canyon's South Rim, springs are fed mostly by water from the Redwall-Muav
aquifer. This Arizona sea of ancient water persists between 2,000 and 3,000
feet below the surface.
However, at present, six wells south of Grand Canyon pump a collective 150 million
gallons per year from this aquifer, a fact well-established by hydrologists
at Errol L. Montgomery & Associates: "… ground water pumping from
the ... aquifer will eventually result in less discharge at the principal springs
… along the South Rim of Grand Canyon."
As complex as most environmental issues are, this one features a palette loaded
with shades of gray. For example, without an alternative water supply for the
park and businesses, (and others using the aquifer at Grand Canyon), shutting
down South Rim wells is difficult at best.
Alternative water supply schemes have the potential to bring other problems
— such as unintended growth along a supply route — that add to that
complexity.
Even so, a dialogue about alternative supplies, water conservation, and demand-side
management is necessary to explore water supply solutions for both Grand Canyon
National Park and the Greater Grand Canyon region.
Recent efforts in the Grand Canyon State to protect ground water may add layers
to this complex mosaic. Arizona environmentalists filed a lawsuit claiming the
state is not protecting streams and other watercourses, and that ground water
pumping has drastically lowered water tables.
Any decision on this lawsuit would apply statewide.
Several groups are working to gain a better understanding of the dynamics of
ground water systems in the Greater Grand Canyon region. This work includes
details about aquifer capacities in the area, delineating capture zones of springs
with ground water models, and figuring out relationships between springs and
other surface water systems.
Notably, Abe Springer at Northern Arizona University's geology
department reminds us that this aquifer, about twice the size of Delaware,
exists in a region where most locales receive less than 12 inches of annual
precipitation, and where there are no regenerating perennial streams.
The aquifer that feeds these Grand Canyon seeps and springs was not pumped until
1989, and wells tapping it must be 2,000 to 3,000 feet deep, so that water does
not come cheaply.
Other unique hydrogeology characteristics, says Springer, include the fact that
every drop that comes out of the aquifer can be measured, and that anything
that is pumped out is going to affect the springs' flow.
So, while key facts and figures are known about human use of Redwall-Muav aquifer
water, little if any is known about this aquifer's recharge.
At a place called Vaseys Paradise, a familiar stop for Colorado River runners
in Grand Canyon, the federally endangered Kanab ambersnail is holding its own
and, apparently, this population is doing well enough that the smaller-than-dime-sized
land snail can be relocated by biologists to try to recover the ambersnail population
at similar habitat at other springs.
Arizona Game
and Fish data show that this 10,000-year-old late Pleistocene Ice Age relict
species lives in association with watercress, monkeyflower, cattails, and rushes
along with a few more common mollusk species.
Although the Kanab ambersnail story is a different, complicated one, the snail's
ecology is an example of the complexity of managing Grand Canyon's seeps and
springs.
Meanwhile, conservationists have pointed to gaps in complicated water laws,
including the Wild and Scenic Rivers Act, federal reserved water rights, and
Arizona's Groundwater Management Act.
The Wild and Scenic Rivers Act and federal reserved water rights doctrine are
not yet applicable to seeps and springs because it is difficult to prove effects
of ground water pumping on individual springs.
Arizona's ground water law does not provide the means for protecting springs.
These law and policy gaps are big enough that it is possible that much of the
diversity of life at the Canyon's seeps and springs will be lost.
It brings to mind the credo: First, do no harm. There is something intuitive
and basic about protecting places where great biological diversity and an abundance
of life occurs.
At the Grand Canyon, these hot spots are its seeps and springs.
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