Draft for discussion
THE CONSERVATION FOUNDATION
SYMPOSIUM ON THE LAW OF WATER ALLOCATION
IN THE EASTERN UNITED STATES
Cosmos Club, Washington, D. C.
October 4-6, 1956
Technical Aspects of Water Management Practices
for the Paw Paw River Basin
Norman F. Billings
THE CONSERVATION FOUNDATION
30 East 40th Street
New York City
Technical Aspects of Water Management Practices
for the Paw Paw River Basin
Norman F. Billings
Michigan Water Resources Commission
The purpose of this paper is to explore the role of applied hydrology in the
development of water and the regulation of water uses in the Paw Paw Basin as ex-
emplary of Michigan areas where consumptive and non-consumptive uses are coming
into competition. It considers this role both with respect to the development of
legislation, in which hydrology is involved chiefly from the standpoint of its
general, basic principles, and to- the actual administration of water management
practices, where the science finds very detailed application.
The Paw Paw Basin consists of some 446 square miles of glacial drift near the
extreme southwestern corner of the state. The topography is gently undulating to
moderately hilly, the soils generally loamy to sandy, and the water table within
a few feet or dozens of feet below the ground surface as a general rule. The
stream system is relatively stable in stage and discharge, with an estimated ratio
of 3.6 to 1 between the 10% and the 90% points on the flow duration curve for the
U.S.G.S. stream gaging station at Riverside. The basin contains many lakes, ranging
in size from a few acres up to 900 acres for Paw Paw Lake, the largest. Some of the
lakes outlet permanently or, more generally, intermittently, to the stream system.
Others have no surface outlet. From information elsewhere in the state, it is assumed
that some of the very smallest ponds, marshes, and "wet spots" express perched water
tables. Water levels of the larger lakes and swamps, the main stream of the Paw Paw
and its permanent tributaries approximate the true ground water table.
A few small reservoirs have been developed by building dams on the larger streams
Topographic maps indicate the possibility of some additional dam sites with storage
for several hundred acre feet of water. Fairly large numbers of small farm ponds
could probably be constructed and undoubtedly some sites exist that would lend
themselves to storage of the rather significant water volumes necessary for operating
supplemental irrigation systems.
Ground water resources may be somewhat above average for the state, both in
area distribution and in potential yield. It is believed that very substantial
quantities are available in the glacial drift throughout much, but not all, of the
Present water use and development
Soils, climate, proximity to markets and other factors in the vast complex that
determine resource usage have led to the development of an agricultural industrial -
Agriculture is devoted, in a large degree to growing small fruits, tree fruits,
and truck and specialty crops, with a consequent somewhat unusual adaptability to
irrigation. Average annual applications of water are in the neighborhood of 6
inches. The practice is growing steadily and rapidly, doubling both in acreage
and numbers of systems about every 3 years. In 1954 the total area under
irrigation was about 5,563 acres and the total water use about 2,340 acre feet or
1,170 day second feet. On the other hand, artificial drainage has been necessary
to make some agricultural lands arable.
Recreational water usage centers about the lakes, whose shores are becoming
heavily built up with cottages and year round dwellings. Stable lake levels are
most desirable for all types of recreational use. Information is not available
as to the extent of recreational developments on streams but such use is undoubtedly
growing, both for residential and sports fishing purposes.
Hydro power is developed at one downstream site, at Watervliet. The degree
of water use there is not known but in Michigan generally hydro power plants use
all medium and low flows.
Industries and municipalities, mostly on the lower reaches of the river, use
the Paw Paw for waste disposal. Their combined waste loading results in pollution
of the river to the extent that it is injurious to the public health, lawful enter-
prise or fish and aquatic life during periods of low stream flow. The pollution
is accordingly unlawful and is being reduced under orders of the Water Resources
Commission. Those orders must be reasonable and cannot require that the reduction
of waste loading be carried any farther than is necessary to abate existing injury.
However, if the low stream flow on which pollution control orders are based is
depleted, the waste loadings, even though reduced, may again cause injury and there-
fore be unlawful and subject to further Commission orders.
The Paw Paw thus contains all the types of water conditions, water and land
relationships, aad water use problems that are found in the state. Because each
river basin has its own physical and economic individuality, the degree of those
conditions, relationships and problems varies from basin to basin. Those variations
do not imply the need for different laws or administrative practices in the various
basins. The need, instead, is for flexibility and responsiveness to needs whenever
and wherever they occur.
Hydrology as an Aid in Developing Legislation
Preparatory to enactment of legislation, the hydrologist will be called upon
to report the general magnitude of water resources available, in terms of the uses
they will supply, and how those quantities may be expected to vary from time to
time. This he can do, with respect to surface water, from the records of existing
key lake and stream gaging stations. With respect to ground water, he is limited
to making broad generalizations because data are so deficient. In the Paw Paw
basin, for example, little more can be said than that the ground water resources
appear to be capable of meeting substantial municipal, industrial, and irrigation
needs throughout much of the area. As to lakes and streams in the Paw Paw, like
in most other river basins of southern Michigan, it can be said that recreation,
power development, and mnnicipal/and industrial waste dilution fully utilize the
resources during ordinary drought. The recreation use is widely distributed but
the others are mostly at downstream locations. At other seasons, great quantities
of water escape unused as flood and freshet flows enough, in fact, to meet all
presently conceivable consumptive and non-consumptive uses, if it could be stored
and released as needed.
Under the principles of Michigan pollution control law, the use of streams
for waste disposal is effectively limited by their ordinary low flow. Thus the
Paw Paw in an ordinary spring carries far more water than can be used for waste
dilution. This excess gradually diminishes until at seasonal low, the flow
approaches or reaches the rate upon which pollution control orders have been based.
When and in what quantities the excess flow occurs will be important to the legis-
In addition to knowledge about the resource and its current uses, the legis-
lature will want to have the best possible basis for estimating future needs. The
hydrologist can aid here by investigating recent and current water use trends.
Forecasting likely extension of those trends will call for collaboration by agri-
cultural, municipal, industrial, and conservation authorities.
The legislature will want to know what things can be done to improve the
natural water situation in order that provision for them may be made in the law.
The hydrologist will need to explain the various possible improvement practices
so that their implications may be fully understood, even though the law itself
cannot deal with them in any detail. For example, one such practice, on-channel
storage of excess water, involves some rather complicated management problems
in distinguishing stored water from natural stream flow that need to be appreciated
by the law-drafters if they are to provide properly for such projects.
Hydrology as an Aid in Post-Legislation Water Management
Far different from these simple duties are the tasks facing the hydrologist
in actual administration of water rights law. Now, instead of dealing with general
principles he must occupy himself with very specific facts.
Establishing minimum stream flows and lake levels
The law will provide in some way for the protection of time-honored rights -
of that we can be certain. The first job in water management at the Paw Paw basin,
then, will be to identify and evaluate those rights in exact terms cubic feet
per second, acre inches, hundredths of feet in water level elevation. This will
be necessary even though the rights in question may never before have been recognized
with such exactitude, in order that additional needs may be filled to the greatest
It is to be hoped that the law will at least say how such determinations shall
be made. That can be done as in the new Mississippi law, which calls for the use
of past stream-discharge records in computing or estimating minimum flows to be
reserved for non-consumptive uses. But because some streams even at low flow
carry much more water than is needed for any present use, the law should also
provide an alternate basis for deciding how much the flow of such streams might
safely be depleted.
Possibly that alternate could be expressed in the law as a rate of stream flow
per unit of drainage area, as, for example, ".4 cfs/sq.mi." In that case, as with
the past-record approach, the hydrologist's work is mainly collecting and analyzing
a great deal of stream-flow data. If, however, the law only relates the propriety
of diversions to limits which are set by the needs of fish life, then the hydrologist
together with the fish habitat authority have a very difficult job. The writer's
understanding, from Michigan fisheries authorities, is that only research and ex-
perience will show how much water is required under the various possible conditions,
to sustain fish life on this stream or that.
The problem of ascertaining minimum lake level conditions that are compatible
with existing rights and needs is appreciably simpler than the identification of
minimum acceptable stream flow. Michigan has considerable experience under statu-
tory law in the establishment of "normal" levels, which are reasonably susceptible
of determination with respect to the record of past levels, to existing development
of shore properties, and to fish spawning conditions.
Regulation of diversions
After minimum stream flow rates and lake level elevations have been set,
the administrative functions come into full play with the allocation of priorities
to consumptive uses and the regulation of those uses with respect to each other
and to minimum flow or levels. Hydrologic activity requisite for this phase
consists of maintaining very accurate and up-to-the-minute knowledge of stream flow
throughout the entire system especially when the flow declines to rates where
termination of lowest priority diversions is imminent. Such knowledge is, of
course, absolutely essential to permit all uses when possible and to terminate
such uses in order of their priorities exactly when stream conditions so require.
Many low-flow stream gaging stations and lake level gages will have tote main-
tained and checked frequently during critical periods.
A situation that will complicate stream flow appraisal is the intermittent
nature of irrigation pumpage as practiced in this state. As pumps are started
or stopped, the effect on flow of a stream moves downstream rather slowly at
rates that depend on the characteristics of that particular stream. The
hydrologist will have to learn those rates for every critical reach of stream
so that he can know how much the flow at a check station at any particular time is
influenced by the various upstream pumping activities. Metering devices on the
pump outlets may be necessary to permit accurate accounting of water consumption.
Excess Water Storage On-Channel
Where on-channel reservoirs for the storage of excess water are developed
on permanent streams a problem of distinguishing the stored quantities from those
represented by the natural stream flow will be presented. The limitations in
accuracy of stream measurement techniques may make it very difficult to balance inflow
against outflow and thereby to evaluate the volume being released from storage at
any time. Another way of getting at the answer to this problem might consist of
developing a storage-curve for each reservoir and permitting use at the rate by which
reservoir storage is depleted. Same computed evaporation loss should, theoretically,
be subtracted from the allowable use quantity. We doubt the practicality of attempt-
ing to assess actual evaporation losses and are at present inclined to think that
a flat monthly loss rate might logically be applied, on an area basis for example,
5" per month or whatever other figure careful study indicates is proper, times the
reservoir's average water surface area for the month.
Excess Water Storage Off-channel
It would seem that the law should authorize the detention of overland runoff
for beneficial uses. Little administrative supervision over such projects would
be necessary and the main type of hydrologic consultation indicated would be advice
as to pond construction and drainage area requirements for best results.
Ground Water Problems
The Paw Paw basin, like many other irrigable areas in Michigan, offers sub-
stantial potentialities for obtaining water from the ground. Except as ground
water supplies are permanently depleted, their production is largely at the expense
of stream flow. Where pumping lowers the water table beyond reach of phreatophytes,
evapo-transpiration losses will be reduced. Significant water savings may result
in some cases. However, widespread and heavy pumping is bound to cause some
reduction in stream flow and lake levels. The effect will not be as drastic as
from direct surface water diversions, but will tend to be spread over weeks or months.
It will be least at the beginning of the irrigation season and will increase as
the season progresses.
Pumping tests will be useful in estimating the degree of diminution in flow
or lake levels which may result from ground water production. Such tests are
laborious, expensive, and require highly skilled technicians for their interpreta-
tion. We would look for them to be employed in the development of general guides
to ground water management rather than on a wholesale basis.
It is difficult at present to visualize the criteria which might be selected
as bases for regulating ground water pumping. It seems unavoidable that production
from the ground must enjoy a favorable position in relation to direct diversions
from surface water. When streams and lakes reach base conditions, the enforced
cessation of diversions therefrom will at once terminate their effects. But
ordering a well shut off at that time, half a mile distant from a stream, will
produce no observable response at all in the stream. Shutting off a hundred
wells might cause some improvement in stream flow after a period of weeks, but the
critical conditions may well have been ended by then. Unless a benefit is pro-
duced, we can see no point in requiring the cessation of pumpage. If wells are to
be allowed at all, they might as well aW allowed to operate continuously. A more
logical approach might lie in limiting the total allowable monthly pumping from
wells within the drainage basin. But every well's pumpage reduces stream flow to
some degree and thereby aggravates the conditions which we seek to prevent in reserv-
ing base flows from direct diversion. No benefit would result from reserving a
greater flow in an attempt to anticipate and accommodate the effects of ground water
pumping. The effect of diversions on a surface stream can be terminated very quickly
by stopping the diversion. The effect on stream flow of pumping from the ground, on
the other hand, will persist long after the pumping is stopped. But who can fore-
cast stream flow conditions with sufficient accuracy to substantiate, in court, the
need for shutting off wells weeks ahead of time?
Indirect improvement through cooperative effort
Although we use the word "inter-related" a great deal in discussing the
basic principles of water management, we must remember that in many cases, the
relationship is highly unilateral, with most if not all the effects of a given
practice occurring downstream. Downstream interests seeking to improve their water
resources can hardly expect upstream interests to foot the bill, however meritorious
a particular project may be. Where the benefits accrue to a large number of people
it may accordingly be worthwhile for them to subsidize such indirect improvement
measures as reforestation, soil conservation, infiltration reservoirs, ground water
recharge and even in some cases, drainage. Procedures for carrying out such group-
sponsored action should be provided in the law. The hydrologist, soil conserva-
tionist and geologist in collaboration can provide useful advice as the best
location and choice of such practices.
It is apparent that the systematic management of water resources in the
Paw Paw basin will involve enough continuous data collection and study to con-
stitute some expense. The day to day regulation of uses that is necessitated by
natural flow variations will certainly be a nuisance to the water users. However,
the more guesswork is permitted and the more casual regulation is, the less fair
will be the management to all concerned. The writer anticipates little active
opposition to a system that is handled with scrupulous care and the greatest
possible accuracy. The need for water is growing so critical that all parties to
the problem can be expected to insist on such accuracy, which can be maintained only
by keeping very close watch on water resource conditions.