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regulators in these states have limited
ways to cut back on use. Thus, future con-
servation rests mostly with individual
water right owners, who will make deci-
sions about reducing their use.
THE TECHNOLOGY POTENTIAL
States encourage locally developed efforts
to conserve the aquifer supply. Texas
requires groundwater conservation districts
that share a common aquifer to set “desired
future condition” aquifer goals. Once these
goals are set, the Texas Water Development
Board (TWDB) uses groundwater avail-
ability models to estimate how much
groundwater can be pumped to achieve the
goals (TWDB, 2016). In Colorado, the
Republican River Water Conservation
District (RRWCD) encourages landowners
to enroll irrigated acres into USDA pro-
grams for conversion to dryland acres, in
exchange for payments. The RRWCD
charges farmers an annual water use fee
of US$14.50 per irrigated acre, which
helps fund payments for fallowing acres
(D. Daniels1, 2016, personal commun.).
Precise water management has the
potential for irrigators to maintain crop
yields and revenues on less water by using
efficient irrigation systems and optimizing
when to water. Kansas is testing this
approach at “water technology farms”
(Kansas Water Office, 2016). The Texas
Water Plan has an irrigation water savings
goal of 639,000 acre feet annually by 2020
through implementing more efficient irriga-
tion systems and methods (TWDB, 2016).
Irrigation systems improve efficiencies,
with more water taken up by the crop and
less lost to evaporation, surface runoff, or
deep percolation. Inefficient flood irrigation entire High Plains aquifer conditions.
(gravity flow down furrows) has largely
given way to more efficient center pivots
(large circular sprinklers). Highly efficient
subsurface or mobile drip irrigation is
gaining popularity. Soil moisture probes in
fields with data accessible on a smart phone
or tablet allow farmers to monitor moisture
in the crop root zone and apply water at the
most effective times. Precise crop water
management is a big shift from the typical
pattern of turning on an irrigation system
in the spring and turning it off at the end of reports are encouraging; irrigators are stay-
the growing season.
More efficient irrigation does not neces-
sarily result in water conservation, a
1 D. Daniels is general manager of the Republican River Water Conservation District in Colorado.
common assumption. The adoption of
more efficient irrigation systems in Kansas
led to more irrigated acres of water-inten-
sive crops (Perry, 2006). More efficient
irrigation systems can operate with lower-
capacity wells. Many farmers invest in
more efficient systems when their well
capacities decline to be able to continue
irrigation of the same type of crops
(Peterson and Golden, 2005). When well
capacities declined in the past, producers
abandoned wells and switched to dryland
farming; new systems allow irrigation to
continue from lower-yielding wells. In
effect, it allows operators to drain the aqui-
fer more completely. Unless irrigation is
done with real conservation, not just the
limits of the well capacity, new technolo-
gies could exacerbate aquifer declines.
Aquifer data is critical to conservation
efforts. It provides a strong foundation for
policy makers, water managers, and water
users to evaluate options and add confi-
dence to their decisions. It also allows
evaluation of the impact of decisions,
which may range from business as usual to
cutbacks in water use. Data on Kansas
water wells, annual water use by water
right, irrigation systems, and water levels
in a network of 1,400 wells in the High
Plains aquifer goes back several decades.
The data is publically available online,
with tools for mapping of water level
trends in a well or area of interest (www.
kgs.ku.edu/HighPlains/index.shtml). The
data is a powerful resource for understand-
ing the aquifer and modeling future aqui-
fer conditions. Colorado, Texas, and other
states also collect and post data online and
are rapidly expanding their water data-
bases and models. The U.S. Geological
Survey uses the state data to report on the
Information transparency with the public
builds trust and increases awareness.
Widespread conservation may hinge on
voluntary, collective commitments to goals
that extend the water resource further into
the future. In a 99 mi2 area of northwestern
Kansas, irrigators entered into a voluntarily
proposed, but mandatory once adopted,
five-year conservation plan with reductions
of water use by 20%. Now in its fourth year,
ing within the reduced water use levels and
reasonable crop yields are being achieved,
www.geosociety.org/gsatoday
while extending the life of the aquifer sig-
nificantly (Golden, 2015; Butler et al.,
2016). Whether that commitment happens
over a wider area remains to be seen.
REFERENCES CITED
Buchanan, R.C., Wilson, B.B., Buddemeier, R.R.
and Butler, J., Jr., 2001, The High Plains Aquifer:
Kansas Geological Survey, Public Information
Circular 18 (revised 2009, 2015).
Bureau of Reclamation, 2011, Colorado River
Basin Water Supply and Demand Study: U.S
Department of Interior, Status Report, Interim
Report No. 1 (June 2011).
Butler, J., Jr., Whittemore, D., Reboulet, E.,
Knobbe, S., Wilson, B., Stotler, R., and Bohling,
G., 2016, High Plains aquifer index well
program: 2015 annual report: Kansas Geological
Survey Open-File Report 2016-4, 179 p.
Cruse, R.M., Devlin, D.L., Parker, D., and Waskom,
R.M., 2016, Irrigation aquifer depletion: the
Nexus Linchpin: Journal of Environmental Studies
and Sciences, v. 6, p. 149–160, doi:10.1007/
s13412-016-0369-6.
Golden, B., 2015, Monitoring the Impacts of
Sheridan County 6 Local Enhanced Management
Area: Kansas State University, Interim Report
for 2013–2014.
Kansas Water Office and Kansas Department of
Agriculture, 2015, A Long-Term Vision for the
Future of Water Supply in Kansas: Kansas Water
Office, 81 p.
Kansas Water Office, 2016, Field Day Showcases
Water Technology Farms: Topeka, Kansas,
Kansas Water Office, http://www.kwo.org/News-
Events/PressReleases/Rls_
WaterTechFarmFieldDay_080216.pdf (accessed
Nov. 2016).
McGuire, V.L., 2009, Water-level changes in the
High Plains aquifer predevelopment to 2007,
2005–06, and 2006–07: U.S. Geological Survey
Scientific Investigations Report 2009-5019, 9 p.
McGuire, V.L., 2014, Water Level Changes and
Change in Water in Storage in the High Plains
Aquifer Predevelopment to 2013, and 2011–2013:
U.S. Geological Survey Scientific Investigations
Report 2014-5218, 14 p.
Perry, C., 2006, Effects of Irrigation Practices on
Water Use in the Groundwater Management
Districts within the Kansas High Plains, 1991–
2003: U.S. Geological Survey, Scientific
Investigations Report 2006-5069.
Peterson, J. and Golden, B., 2005, Evaluation of
Water Conservation from More Efficient Irrigation
Systems: Kansas Water Office, research report.
Texas Water Development Board, 2016, 2017 State
Water Plan—Water for Texas: http://www
.twdb.texas.gov/waterplanning/swp/2017/
(accessed Nov. 2016).
Whittemore, D.O., 2012, Geochemical Identification
of Saline Water from an Irrigation Well in North-
central Stafford County, Kansas: Kansas
Geological Survey Open File Report 2012–21.
MANUSCRIPT RECEIVED 31 AUG. 2016
REVISED MANUSCRIPT RECEIVED 18 OCT. 2016
MANUSCRIPT ACCEPTED 20 NOV. 2016
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