Water Issues
In desert environments water is always an issue.
As the current drought continues awareness is growing and government
officials are becoming more aware than ever how critical an issue it is
for the state. Some say that there is sufficient water for Southern
Arizona available from the Colorado River via the Central Arizona
Project.
Problems with using CAP water as a substitute
to groundwater
Many have suggested that as long as we have CAP water to fall back on, we
need not worry about dwindling groundwater reserves. However, the current multi-year
drought has some asking whether there is sufficient water in the Colorado
River (the source for CAP water in Tucson). Is the current drought real or
just sensationalism generated by newspaper articles.
Recent scientific evidence indicates that it is not only more severe than
the drought that caused the dust-bowl days of the 1930's but possibly the
most severe drought in the last 500 years. Current stream flow levels in
the Colorado River are half what they were in the dust-bowl days of the
1930's and some experts suggest that based on recent data, the current
drought could last another 10-15 years. Read the Associated Press news
article on this topic for more details:
http://msnbc.msn.com/id/5239212/. The Associated Press article was based
on data in a U.S. Geological Survey report
http://water.usgs.gov/pubs/fs/2004/3062/.
Further evidence of the severity of the current drought comes from the
formation of drought management taskforces. See the State's response
Governor Orders Drought Plan and the federal government's response
Water 2025: Preventing Crises and Conflict In the West
Read a very thorough report prepared by the Water Resources Research
Center, College of Agriculture, University of Arizona on water and
sustainability for the Tucson area:
Water in the Tucson Area: Seeking Sustainability
Why should I be concerned? Aren't there officials
that ensure that we have enough safe water for the state?
Well, yes and no. The Arizona Department of Water Resources (ADWR) is
tasked with handling water policies for the state. But special interests
have their ways of subverting even the best of intentions and there are
some loopholes in the current policies. The ADWR vision
statement is:
| " To ensure a long-term, sufficient, and
secure water supply for the state, and to develop public policy
that promotes efficient use and equitable distribution of water
in an environmentally and economically sound manner." |
How do they propose doing this?
ADWR requires that any new subdivisions that are
not within service areas of major water providers like Tucson Water or
Salt River Project must obtain from ADWR, a "100-year water assurance certificate". They require that developers get a
hydrologist to ascertain whether or not there is a 100 year supply of
water in the aquifer to provide water for the development and that it is
of sufficient quality. They also require that the specified means of
obtaining water meet the overall goals of ADWR for that area. The ADWR
then reviews the data and if approved,
issues a 100 year water assurance certificate.
For more details on the 100-year assured water
program see the information in the
ADWR brochure
One of the goals of the ADWR is to have a balance
between the amount of groundwater pumped for municipal uses and the
amount of water recharged into the aquifer. Their "safe yield" policy is
an effort to maintain Arizona's critical underground water supplies as a
renewable natural resource.
| "Safe-yield
is the long-term balancing of groundwater withdrawals with the
amount of water naturally and artificially recharged to AMA
aquifers." |
See the
ADWR brochure for more info
on the safe-yield concept.
So where does the water come from for
recharge?
This is where the system fails. Under the terms of
the 100-year certificate for the recent Black Horse Ranch subdivision,
the developers are allowed to pump only 8% of
that 100-year groundwater supply and all subsequent water is supposed to
come from
other "renewable water sources" in order to achieve a balance between groundwater
pumping and recharge into the aquifer. Consequently, the 100-year
assurance certificate issued to the Black Horse advisors is really only
an 8-year assurance of groundwater availability. Some recharge can come from
wastewater that has been treated and safely recharged into the aquifer
and some water is naturally recharged from rainwater runoff. Surface water
such as the Salt River or Colorado River water is also considered a
"renewable" source but is not available in this area. In the
case of the Black Horse Ranch developers, they were able to take
advantage of a loophole in the "safe yield" requirements that
enables developers to disregard the 8% limitation and use groundwater
exclusively for their new developments.
How do developers bypass the requirement to
maintain a balance between
recharge and groundwater pumping.
The Black Horse
developers took advantage of a program that works with ADWR and allows
the developers to do the following:
1) the developer selects a water company (Los Cerros Water in this case)
who provides water from groundwater pumping and keeps track of how much
water each homeowner goes over the calculated 8% per year allotment.
2) the developer enrolls the subdivision in the Central Arizona
Groundwater Replenishment District (CAGRD) and an equivalent
volume of CAP water is purchased to compensate for how much they go over
the 8% allotment. The water company tracks each households overuse
information and reports it to the CAGRD and to Pima County Tax
Assessor's office who then adds charges to tax bills.
3) CAGRD is then responsible for "recharging the aquifer" by dumping the CAP water
(or "other lawfully available source") into
"replenishment facilities" in Avra Valley within the next 3
years
4) costs of this water replenishment are assessed to homeowners via
their County tax bills
Note that homeowners are assessed both by the
water company for all groundwater used and by the County for their portion of
the CAP water recharged via the CAGRD.
Effectively the homeowner could potentially be
charged twice for 92% of their their water usage. And if there
are "shared use areas" within the subdivision (parks, playgrounds,
picnic areas, etc) that require watering, the homeowner's association
passes on the costs to homeowners via association
fees for any CAGRD recharge required on those "shared use
parcels".
In the Catalina area, that means that
water companies that supply water to these new
developments can bypass the groundwater usage limitations imposed by
ADWR provided
that the developer has enrolled the subdivision in the CAGRD. By doing so, they are in full compliance with ADWR
requirements even though no water was
recharged back into the local (Catalina area) part of the aquifer. The
ADWR estimates that currently water levels in the local
aquifer are dropping at roughly one foot per year but that amount
will increase rapidly as the local population (which is expected to
triple within 20 years) rises in this area.
A map from the Water Resources Research Center at
the University of Arizona shows groundwater flow in the Tucson Basin and indicates that recharge in the Avra Valley area
flows generally north and west and therefore would not help much in replenishing groundwater
resources in the aquifer under Catalina or Oracle Junction.
The legal requirements of this
CAGRD program are complex and are being debated at many levels. For more
information on this see
Proposed Law Allows CAGRD to Recharge Less Water
Isn't there plenty of groundwater in our part
of the aquifer?
Developers proposing new developments in the area
have told us that there is, but if you look at the size and scope of
projects in the area that would triple the population over the next 20
years, it becomes less believable. The recent Black Horse and Eagle Crest
developments will add over 1300 new families,
the High Mesa development will likely add another
150-400 families. In addition there have been proposals for a Willow
Springs development north of Oracle Junction that would encompass
some 10,000 or more new families on 4600 acres
and a Saddlebrooke Ranch proposal near there that would add nearly
12,000 new families.
Note on the map the
existence of the Page-Trowbridge radioactive dump site at the edge of
the proposed Saddlebrooke Ranch development.
How safe is CAP water for drinking?
To be sure, groundwater in the Tucson area has had
its share of contamination problems but what many people don't know is
that CAP water is not safe for human
consumption as it comes from the canal. In the long trip
across the desert to Phoenix and then down to Tucson in open canals a
large percentage of the water evaporates leaving behind high levels of
sulfates, chlorides and other particulates. Its
high salinity causes corrosion of pipes and can effect the growth
rates of some plants. In order to make the
water safe it must be blended with groundwater and treated with
chemicals. For a good discussion
of water quality issues of both groundwater and CAP water in the Tucson
area see the report
Ensuring Safe Drinking Water from the Water Resources Research
Center at the U of A.
Problems with using treated water to replenish the
groundwater aquifer
If the goal is to use chemically treated CAP water to replenish the
groundwater in the aquifer, are we not polluting the very source of
clean water we use to blend with CAP water to make it safe for our
consumption?
Aside from the cost issues, there are health
issues to this. A recent Arizona Water Resources study by U of A
researchers indicates that using treated water for recharge can damage
the aquifer by introducing trihalomethanes (THMs), a carcinogenic compound
into the groundwater. See the article
Recharging Treated Water May Alter Groundwater Quality
Does the Page-Trowbridge dump site affect us?
The Page-Trowbridge dump
site is a landfill that was used by the University of Arizona for about
30 years as a
dump site for radioactive waste from biomedical and other research conducted at
the U of A along with similar waste from other Arizona universities and
hospitals. A pair of Arizona Wildcat newspaper articles in 1999 revealed
damaging facts about the dump site. In one article it was reported
| According to UA estimates cited in the report, roughly 280
tons of radioactive material were buried at the site prior to
1962.
In addition to radioactive material, chemical wastes from UA
labs and other facilities were later shipped to the site in
glass, plastic and metal containers that were routinely thrown
into open pits, according to the report.
The outrage begins
Broken containers often resulted in explosive chemical fires
when acids and other volatile compounds mixed together. Fires
were also set intentionally to dispose of the waste, according
to a UA memo cited in the report.
The report states that burning at Page Ranch took place over
an 11-year period, during which the fires were often doused with
water to put out the flames. |
Another September 29, 1999 UA wildcat article
reported:
| According to the UA, 43,200 pounds of radioactive material
was dumped in unlined holes in one year. Containers of
radioactive waste were tossed into pits and covered with soil.
Liners weren't used until 1983, and the lab packing used was for
the intent of later exhuming the material, an undertaking
estimated to cost $7-10 million in 1986 - the year the
landfill's dumping ended. But the closure plan was postponed
until the 1990s.
All this is 3.3 miles from the town of Oracle's sole water
supply and aquifer, and not much farther away from the wells
providing water for Catalina and parts of Tucson. Carbon tetra
chloride, trichlorethylene and chloroform were detected at
levels from 700 to 800 feet below ground.
In 1989, the soil and soil gas was found to be contaminated
with several more volatile organic compounds. |
The UA eventually was forced to discontinue
use of the dump site. One of the articles notes that:
| ... the situation heated up when the Environmental
Protection Agency became involved.
"In 1981, the EPA laws changed and they (the UA) had to file
for interim permit status to continue their operations," Parton
said.
The request was denied and the UA ultimately failed to gain
the interim status that would have allowed them to continue
dumping at Page Ranch through 1995.
In 1984, Oracle citizens formed an ad hoc committee to demand
that the UA stop dumping at the site and take appropriate action
to stabilize it.
In the end, the UA decided in 1986 to close the landfill when
it became apparent that the site was becoming more of a
liability with each passing year. |
See:
http://wc.arizona.edu/papers/93/27/01_1_m.html and
http://wc.arizona.edu/papers/93/27/04_3_m.html for photos
and the full
articles.
Clearly, we all need to become involved in
water issues and assist the various government agencies in ensuring that
we continue to have adequate supplies of safe water for the future.
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