Ground-Water Research 

in the United States

GEOLOGICAL SURVEY 

CIRCULAR 527
Ground-Water Research 

in the United States

By O. M. Hackett

GEOLOGICAL SURVEY CIRCULAR 527

Washington 1966
United States Department of the Interior

STEWART L. UDALL, Secretary

Geological Survey

William T. Pecora, Director

Free on application to the U.S. Geological Survey, Washington, D.C. 20242
Ground-Water Research in the United States1

By O. M. Hackett

The main stimulus and support of ground-water hydrology 

has always been the human need for water supplies, and the 

glory of ground-water work has been that human betterment, 

through the development of more abundant, convenient, and 

wholesome water supplies, has followed closely in the wake 

of our work. However, this utilitarian urge has become so 

extreme that at present in this country practically all funds 

available for ground-water work must be \jsed in applying our 

knowledge to specific ground-water surveys or water-supply 

problems, with virtually no opportunity for research work 

except as it is carried on inadequately and almost surreptitiously in connection with these utilitarian projects. 

We are constantly compelled to follow the wasteful course of 

applying the little that we now know instead of being able to 

devote a reasonable part of our efforts to the fundamental 

task of developing the basic principles of the science so 

that in the future we will have something more worth while 

to apply. What is primarily needed at the present is not 

more money for ground-water work but o more rational use 

of the money that is spent.

With these words, O. E. Meinzer (1934, 

p. 30 31) summarized the status of groundwater research three decades ago. What has 

happened since then? How do we fare today, 

and what is the promise of tomorrow? These 

subjects I will discuss. But first, let us review the early history of ground-water research in the United States, extending it back 

to the end of Meinzer's day shortly after 

World War II. For background I am indebted 

to Meinzer's own writings and to those of my 

colleagues in the U.S. Geological Survey. For 

detailed summaries of the development of 

ground-water hydrology, including research, 

you are referred to papers by Meinzer (1934, 

1942) and by Ferris and Sayre (1955). The 

latter paper includes an extensive biblioggraphy of the principal developments before 

1955.

There is very little record of scientific 

ground-water work in the United States be1Presented December 1, 1965, at the First Annual Meeting of 

the American Water Resources Association, Chicago, Illinois.

.fore 1877, when T. C. Chamberlin's first report on artesian conditions was published. 

This was followed by a more comprehensive 

report in 1885. These two papers may be 

said to mark the start of ground-water research in the United States.

Beginning about 1890, the interest in 

ground water as a resource quickened. Consequently, and with stimulus from John 

Wesley Powell, the second Director of the 

Geological Survey, ground-water studies were 

begun in this agency on a small scale. Early 

studies, made by geologists of the Geologic 

Branch as a part of their geologic fieldwork, 

were largely descriptive and were concerned 

principally with where water was to be found. 

Included among the first studies were investigations in the Arkansas Valley by G. K. 

Gilbert, in the central Great Plains by N. H. 

Darton, and in the High Plains by W. D. 

Johnson. In the tradition of the geologists of 

that day, these early investigators were keen 

observers and masters at drawing a maximum of sound conclusions by inference from 

sparse data. They established geology as the 

cornerstone of ground-water hydrology, and 

the Geological Survey as the principal Federal agency concerned with studying the 

ground-water resources.

Meanwhile, work by other investigators, 

notably Alien Hazen, Franklin King, and 

Charles Slichter, was directing interest in 

the United States for the first time in any 

substantial degree to the quantitative aspects 

of ground-water hydrology. A milestone was 

passed in the early 1900's when Slichter devised methods of measuring rates of groundwater movement. His studies of underflow in 

the South Platte River, Arkansas River, and 

Rio Grande Valleys marked the beginning of 

quantitative ground-water studies.
From these early beginnings groundwater work in the United States progressed 

slowly until the mid-twenties. Nevertheless, 

events during this period were to lay the 

foundation for much of the ground-water research to come later. Most of the effort, by 

a handful of investigators in the Geological 

Survey, was concerned with geology as it 

controlled the occurrence and movement of 

ground water. From this work stemmed 

Meinzer's (1923) classic Water-Supply Paper 

489, which remains today a basic groundwater reference. But more important than 

published reports were two men and their 

ideas. The men were W. C. Mendenhall and 

Oscar Meinzer.

Mendenhall, later Director of the U.S. 

Geological Survey, was to kindle and direct 

Meinzer's early interest in ground water; 

and Meinzer, in leading ground-water activities in the Geological Survey, was to set a 

new pattern from which ground-water hydrology in the United States would evolve as 

a distinct phase of science. Mendenhall's 

contribution can be summed up best in terms 

of Meinzer's recollections:

I wish to mention two lessons that I learned from Mendenhall. The first was to take ground-water work seriously. 

There was a tendency at that time for geologists assigned to 

the ground-water investigation of an area to devote themselves to the geology of an area for its own sake and to give 

only scant attention to the ground water. In some cases the 

geologic data obtained in a season of field work would be 

supplemented with information in regard to the wells obtained by sending circular letters to the postmasters in the 

area covered. Mendenhall was bitterly critical of this frivolous attitude toward ground water, and I was wholly in accord with him.

Another lesson that I learned from Mendenhall concerned 

the importance of the quantitative problems in ground-water 

work. He worked in southern California, where the major 

problems even at that time related to the quantities of 

ground water permanently available, and his thinking was always in quantitative terms. Thus it happened that all 

through the lean years we were concerned with quantitative 

methods. Although we did not have funds or personnel to 

make adequate tests of the methods we devised, we were 

nevertheless laying the foundation for important results in 

later years.

Meinzer learned his lessons well. In 

subsequent years he emphasized the study of 

ground water as a worthwhile goal in itself 

and broadened ground-water investigations 

to include all facets of the hydrologic cycle 

that impinged thereon. To help provide the 

quantitative input he drew in the engineer 

and physicist, concerned principally with 

fluid mechanics, to team with the geologist,

concerned principally with describing the 

earth medium. With V. C. Fishel, a physicist (Meinzer and Fishel, 1934), he investigated experimentally in the laboratory and 

proved that Darcy's law is valid for the extremely low gradients common in groundwater flow. He translated the doctoral dissertation of G. Thiem, which he found by 

chance in the Survey Library. This gave him 

the steady-state mathematical equation for 

determining permeability and transmissibility by a field pumping test. Slichter (1899) 

had published an identical equation, except 

for form, but apparently its potentialities 

were not recognized. Meinzer then arranged 

for Wenzel (1942) to make an extensive field 

test of the Thiem method at Grand Island, 

Nebr., and from this test a better understanding was obtained of its potential 

application.

The broadened interest and outlook toward ground water is reflected by the wide 

variety of subject matter that received attention during the period extending from the 

midtwenties to World War II. This included 

the water budget, the relation of salt water to 

fresh water, the relation of ground water to 

surface water, recharge, ground-water discharge by phreatophytes,the compressibility 

and elasticity of artesian aquifers (Meinzer, 

1928, in part on the basis of ideas suggested 

by D. G. Thompson), and the chemistry of 

ground water. In particular, attention was 

given to the theory of ground-water motion. 

The storage and transmission characteristics of porous media were studied in both 

laboratory and field, and methods for determining these characteristics quantitatively were derived and tested. The conceptual explanation of the functional characteristics of aquifer systems by Theis (1938, 

1940) was an outstanding advance. The development of the nonsteady-state equation by 

Theis (1935) provided the means for quantifying those characteristics and showed 

clearly that time can be an important boundary in hydrologic analysis. This work, which 

since has been extended by colleagues of 

Theis to cover variations from ideal conditions, represented a major breakthrough in 

the search for quantitative principles that 

might be applied to investigational procedures. Notable also was the development at 

about the same time of the theory of fluid 

motion through porous media by Muskat 

(1937), and a comprehensive treatise on the
theory of ground-water motion by Hubbert 

(1940). Together, these gave the groundwater hydrologist new analytical tools and 

concepts for solving ground-water problems.

The end of World War II approximately 

marks the end of the formative period of 

ground-water hydrology. Ferris and Sayre 

(1955, p. 716-717) aptly describe the early 

part of this period as one of rugged individualism. "Geologist, engineer, and physicist, 

each motivated by some immediate problem, 

attacked only that phase of ground-water hydrology which related to his specific problem, and only those aspects that fell within 

his own field of competence," They note also, speaking of the theory of ground-water 

motion, that in the early days there was 

little interchange of information among workers in Europe and the United States; consequently, many parallel developments were 

formulated contemporaneously. In the United 

States the same was true with respect to the 

interchange of information among workers in 

ground water and workers in related fields 

such as soil physics, soil mechanics, drainage 

engineering, and petroleum engineering. The 

close of. this early period was marked by a 

great improvement both in applying the coordinated effort of workers from different disciplines and in the interchange of information.

Throughout this time there was no financial support for a ground-water research 

program in an organized sense. Research 

had to be carried out in the U.S. Geological 

Survey, as Meinzer noted, almost surreptitiously in connection with utilitarian projects; 

it was made possible because of the encouragement of interested State geologists and 

engineers who helped support the work and 

contributed some of the ideas. There was no 

formal training for ground-water hydrologists at best here and there a geology department would offer a course in groundwater geology or a civil engineering department would offer a course labeled "hydrology." As a consequence, research was 

carried out by men whose training initially 

had oriented them toward other (though 

related) careers. There was little research 

or research interest in ground water by 

universities and colleges; thus the potential 

in the academic manpower pool was untapped.

From these circumstances stemmed 

Meinzer's complaint that "We are constantly 

compelled to follow the wasteful course of

applying the little that we now know instead 

of being able to devote a reasonable part of 

our efforts to the fundamental task of developing the basic principles of the science 

so that in the future we will have something 

more to apply."

Nevertheless, in retrospect, despite the 

disadvantages attending the circumstances of 

that day, the sum of these circumstances 

tended toward molding much that is good. It 

tended toward creating a research attitude 

among the people who were engaged in 

ground-water studies, even though these 

studies were utilitarian. The worker of that 

day had no handbook, nor was there an elite 

corps to whom he could turn for principles 

and for guidance in applying them. If he were 

to solve his problems, he had to engage in 

research personally. This sort of challenge 

led some high-caliber people into the field 

who might not have been attracted otherwise, 

and it yielded results that were characterized by relevance to water problems. For example, Theis was not conducting research 

into the theory of ground-water motion when 

he developed the nonequilibrium formula; 

rather, the original transient case was developed from a geological standpoint by 

Theis to enable him to solve a practical field 

problem. In his words (Theis, 1963, p. 28):

In the days when this equation was being worked out, 

which was before publication of Muskat's book or King Hubbert's paper on ground-water flow, I was faced with the proposition of how to think about pumping from the High Plains, 

particularly from the Llano Estacado, or Staked Plain of 

Texas. Here, very evidently we could not think of a small 

withdrawal of water from a water body, which had several 

times the capacity of Lake Mead, in equilibrium terms, which 

had been the practice up to that time. So I was driven to find 

a new way to think about the problem and, of course, as any 

of you who have read the paper will know, I ended up with a 

mathematician friend who helped me in my quest to find the 

new way.

We turn now to developments during the 

last two decades. The first decade, from 

World War II to the middle fifties, was one of 

transition. The substantial increase in water 

use accompanying peacetime growth after 

World War II gave added impetus to the interest in water, and the resulting clamor for 

more and better basic data brought about a 

rapid expansion in programs of water-data 

collection and interpretation. Research, 

though carried on as always in conjunction 

with these programs, became progressively 

smaller in proportion to the total effort. The
need for an increased emphasis on groundwater research had been recognized, however, and progress in this direction was to 

mark the last decade.

In the U.S. Geological Survey, a major 

step toward making a reality of Meinzer's 

dream for a program devoted specifically to 

ground-water research was taken in 1956 

when R. R. Bennett drafted a statement identifying five major areas of research vital to 

an understanding of hydrologic systems. With 

stimulus from Luna Leopold and Nelson 

Sayre, a research section was established 

under Bennett's leadership, and with minor 

modifications Bennett's original statement of 

areas for research became the foundation of 

much of the Survey's ground-water research 

program. For a recent description of this 

program you are referred to Geological Survey Circular 492 by C.L. McGuinness (1964).

Perhaps the most significant event promising an impact on ground-water research 

was the passage in 1964 of the Water Resources Research Act (Public Law 88 379) 

and the establishment of the Office of Water 

Resources Research in response thereto. 

This office already supports 69 projects 

identified as ground-water research. In addition, it publishes annually a catalog of 

water-resources research which should promote the exchange of research information 

(Office of Water Resources Research, 1965a, 

b).

During the past two decades there have 

been no spectacular breakthroughs in groundwater research, but rather numerous advances along many fronts. Shortly after World 

War II Meinzer identified future needs for 

research in eight categories: ground-water 

hydraulics, the zone of aeration, ground 

water-surface water interrelationships, geophysical methods, the mode of ground-water 

occurrence in various terranes, geochemistry, salt-water encroachment, and groundwater contamination. From an earlier review (Hackett, 1964) of the advances made in 

these categories, I repeat the following 

summary;

In ground-water hydraulics, developments 

have taken four principal directions: refinements in aquifer-test methods such as 

those involving the use of image wells (Fer - 

ris and others, 1962); a closer look at the

true nature of the storage coefficient, especially in strata that deform plastically rather 

than elastically; permeability distribution to 

enable economically possible yet reasonably 

accurate extrapolation of limited aquifer-test 

data in setting up electrical analog models of 

aquifer systems; and studies of diffusion and 

dispersion in relation to transport of contaminants (Ogata and Banks, 1961; Ogata, 

1961 and 1963; Skibitzke and Robinson, 1963), 

such as radioactive wastes, and to encroachment of salt water in coastal aquifers (Cooper 

and others, 1964).

The zone of aeration is the "no man's 

land" of hydrology. It has received some 

attention from the ground-water hydrologist, 

who is interested in how water travels 

through it both downward to and upward from 

the water table; from the meteorologist and 

the surface-water engineer, who are interested in its effect on interception of precipitation and modification of runoff; from 

the soil scientist, who is interested in it 

mainly as a reservoir of moisture for plant 

growth; and from the sanitary engineer, who 

is interested in it as a transporter of and a 

temporary or permanent trap for various 

contaminants (Stallman, 1964). Much of our 

present knowledge is qualitative or empirical, however; we are only beginning to investigate the fundamental physics and chemistry of this movement and interaction of 

water and its dissolved and suspended constituents in the zone of aeration. The groundwater hydrologist will have the principal 

role here because of his understanding of 

fluid flow in porous media, and much of his 

effort in the immediate future will be aimed 

at this field.

Ground-water surface-water relationships 

are receiving more attention as hydrologists 

increasingly adopt the "systems analysis" 

point of view in attempting to visualize the 

effects, throughout whole hydrologic systems, 

of various water development and control 

projects. Achievements since Meinzer's 

time include some fundamental work on induced infiltration from streams to wells 

(Rorabaugh, 1953), on filling and emptying of 

bank storage as a result of natural fluctuations in stream storage (Cooper and Rorabaugh, 1963), on analysis of water-level 

fluctuations in wells resulting from tidal and 

other changes in stream storage in terms of 

aquifer characteristics (Ferris, 1963), and on
interchange of fresh and saline water between coastal aquifer and the ocean.

Geophysical methods are being used increasingly in ground-water studies. Prospecting by the surface electrical-resistivity 

and seismic methods, which were used on a 

considerable scale in Meinzer's day, have 

been supplemented on a small scale by magnetic and gravity surveys. Borehole geophysics, however, is the principal current 

tool. The chief advances have been in the 

application of neutron and gamma-ray logging, in the hydraulics of multiple-aquifer 

wells, and in textural and geochemical interpretations from resistivity and spontaneous-potential data. Borehole geophysics is 

expected to be a principal tool in getting 

more reliable information at practical cost 

from wells and test holes for use in the construction of analog models of hydrologic 

systems.

Certain geologic terranes have characteristic hydrologic features which differ 

markedly from those of other terranes and 

which can be profitable studied in terms of 

those characteristic features. Among these 

are carbonate-rock ("limestone"), basalt, 

crystalline-rock, and permafrost terranes. 

Certainly these and other terranes received 

attention in Meinzer's day and before, but 

only in recent years has a more systematic 

effort been made to identify the lithologic 

features responsible for their distinctive 

hydrologic behavior and to measure their 

effect quantitatively.

Progress has been made in measuring the 

effect of certain structural features in damming or channeling underground flow in 

limestone and basalt (Newcomb, 1961); in 

relating the occurrence of water in crystalline rocks to lithologic types, major structures, joint patterns, and topography; and in 

prospecting for liquid water in areas of 

permanently frozen ground. Work is also 

underway on certain features of sandstoneshale terranes, such as texture in relation to 

directional permeability as a guide to patterns of deposition (which would help in extrapolating data to fill in permeability-distribution maps), and "membrane" properties 

of shales in relation to cross-bed movement 

of water in structural basins.

Geochemistry is becoming increasingly 

important as it is realized that some phenomena of water movement can be explained 

only on a chemical basis for example, the 

"membrane" properties of shales mentioned 

above. Many current problems are basically 

chemical, such as high iron content in relation to organic matter, control of acid 

mine water, disposal of radioactive wastes, 

origin of water precipitated in inland areas, 

and maintenance of proper salt balance in 

irrigated areas.

Salt-water encroachment is a potential 

threat wherever ground water is used along 

the coast or along a tidal stream or estuary. 

It is a threat inland too, wherever heavy 

pumping may induce lateral movement or 

upconing of brines. An example of recent 

research achievements in this field is an 

explanation of the difference between the 

classical Ghyben-Herzberg balance between 

fresh and salt water and actual situations 

where the interface was displaced seaward 

as a result of erosion of the salt-water 

front the energy coming from the twicedaily tide-induced fluctuation of the interface. A related achievement is the development of mathematical solutions for the 

positions of the salt-water interface under 

a variety of shore characteristics (Cooper 

and others, 1964). Research also is underway to explain certain anomalous distributions of fresh and salt water as hangovers 

from periods of different sea level hundreds 

or thousands of years ago.

Ground-water contamination is an increasingly important field of study as development becomes heavier and wastes are 

disposed of onto the land surface or into 

surface-water bodies from which they can 

enter the zone of saturation. That contamination has been mentioned in connection with 

several of the preceding subjects simply 

goes to show the broad ramifications and 

potential seriousness of the problem. Of the 

many studies underway in this field, a good 

example is the study of the effects of synthetic detergents on the soil, such as reduction of soil permeability by dispersing 

soil colloids, and of the rate of detergent 

decomposition in various environments. 

Other important studies include those intended to develop criteria for safe disposal 

of radioactive wastes.

In addition to the foregoing, new techniques and methodology have been given 

attention by researchers For example,
much attention has been given to the use of 

analog and digital computer methods for 

analyzing ground-water systems. As a consequence, the use of the electrical analog 

model in ground-water investigations already 

is widespread. Remote-sensing techniques 

are another example of a new development 

that is being studied for possible application 

to ground-water hydrology.

We also see during the past two decades 

among those engaged in ground-water research a maturing of attitudes along the following lines:

1. An increased recognition of the significance of the interrelationship between ground 

water and water in other phases of the hydrologic cycle especially surface water and 

water in the unsaturated zone.

2. An increased recognition that groundwater research extends beyond the purely 

hydrological considerations and encompasses 

economic, social, legal, and political factors 

that relate to water utilization and reservoir 

management.

3. An increased awareness that some elements of ground-water research require an 

interdisciplinary approach by specialists in 

the natural, agricultural, engineering, and 

social sciences.

4. An increased awareness of interests 

shared in common with specialists conducting 

research in other fields, such as petroleum 

geology and engineering, agriculture, drainage engineering, and soil physics.

This summary brings us to the present 

day. What of the future ? In terms of work 

to be done it is clear that more effort must 

be given to all the research areas described 

above. Increased attention must be given to 

developing methods for analyzing regional 

flow patterns and superimposed chemical 

systems. But to make fruitful the application 

of existing or new methods, research must 

be devoted also to improving ways of numerically defining the characteristics of these 

systems. These are high-priority items to 

which the U.S. Geological Survey already is 

applying much effort.

You will note that nearly all the research 

reviewed above is in the realm of hydrology. 

Ground-water research should be concerned 

also with the realm of water planning and 

management including social, economic, and 

legal problems connected with the use and

development of the ground-water resources. 

These, too, are high-priority areas, and they 

have been relatively neglected.

In terms of support, the outlook for 

ground-water research is bright. In its report on the Federal water-resources research program for fiscal year 1966,the Federal Council for Science and Technology estimates the annual research investiment to be 

less than 1 percent of the annual construction 

cost of the total water-related public-works 

program (Federal, State, local, and private). 

In turn, effort identified specifically as 

ground-water research amounts to about 6 

percent of the total Federal water-research 

program, or only a fraction of 1 percent of 

the national water-related pub lie-works program. From these figures one might, and 

perhaps justifiably, draw the conclusion that 

funds for ground-water research are woefully inadequate. I am inclined to think 

otherwise. The increased interest and activity by State agencies and universities, the 

passage of the Water Resources Planning Act 

and the establishment of the Office of Water 

Resources Research, and the continued interest and concern of the Federal Council for 

Science and Technology suggest that funds 

for research, if not adequate now, will be 

soon. However, funds are likely to be adequate only if utilized wisely in the pursuit of 

Meinzer's basic principles and if the temptation of diverting them to water-resources 

appraisals and others of Meinzer's utilitarian studies is avoided.

In terms of trained manpower for groundwater research we are lagging, but even 

here there is cause for optimism. With 

stimulus from the Water Resources Research Act, our universities should provide 

within a few years a source of manpower 

oriented directly toward water-resources 

work and trained with this work in mind.

The future of ground-water research is 

bright. We are compelled no longer to follow 

the wasteful course of applying the little that 

we now know instead of being able to devote 

a reasonable part of our efforts to the fundamental task of developing the basic principles 

of the science so that in the future we will 

have something more worthwhile to apply.

But, more than ever, we need to exchange 

information and especially to coordinate our 

research activities. In the words of Thomas 

and Leopold (1964, p. 1006-1007):
The kaleidoscopic variety of environments in which ground 

water occurs, and of modifications made by man, provide 

magnificent opportunities for any research that results in 

additional basic data and interpretive achievements. Thus 

random research, widely dispersed, can add to our total fund 

of knowledge; but like reproduction by division, its products 

may be new individuals, in new places, but remarkably similar to what we already have. The interrelation of "unknowns" 

points to a need for central direction and coordination of all 

these research efforts. Like water itself, our major water 

problems tend to resist partitioning, and without coordination 

of effort they may well remain unsolved.

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1963, Bank storage and ground-water 

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H. R., and Glover, R. E., 1964, Sea water 

in coastal aquifers: U.S. Geol. Survey 

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lowering of the piezometric surface and 

the rate and duration of discharge of a well 

using ground-water storage: Am. Geophys. 

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* U S. GOVERNMENT PRINTING OFFICE : 1966 0 216-068