Exploiting an Underutilized Trove of Agrohydrology Information:
Interpretation of Hydrographs from Aquifers Supporting Irrigated
Agriculture
Abstract
Many of the world’s major aquifers are under severe stress as a result
of intensive pumping in support of irrigated agriculture. The question
of what the future holds for these aquifers and the agricultural
production they support is of paramount importance in a world of
burgeoning populations, dietary shifts, and climate change. Addressing
that question requires a better understanding of the how and why of a
particular aquifer’s response to pumping. One important, but largely
underutilized, source of information is the data from monitoring well
networks that provide near-continuous records of water levels through
time. Although many regions have such networks operated by local, state,
or Federal entities, the vast majority of efforts are, by fiscal
necessity, focused on keeping the networks up and running. Little, if
any, time is spent on interpreting the acquired hydrographs. The index
well network in the High Plains aquifer (HPA) in central and western
Kansas is an exception, as hydrograph interpretation is an important
program emphasis. Examination of multiyear hydrographs has resulted in
the development of profound insights concerning, for example, the
frequency of episodic recharge, the magnitude and variability of net
inflow, characteristics of the monitored aquifer (continuity, hydraulic
regime, etc.), and the impact of extreme meteorological events. These
insights have allowed us to develop a significantly better understanding
of how the aquifer will respond to proposed management actions; such an
understanding is critical for charting more sustainable paths for
aquifers across the globe. We will demonstrate these points through an
examination of two multiyear hydrographs from the HPA in western Kansas
with an emphasis on the insights that shed light on the prospects for
the sustainability of this heavily stressed system and the agricultural
production that it supports.