A WATER LEVEL CONTROLLED BASIS FOR GROUND WATER USE
Presented by Alton F. Robertson
Thirteenth Annual Water Law Conference
Vail Colorado-January 1994
Groundwater withdrawals and use have been regulated in Florida and in the
Eastern US based principally on restricting the quantity allowed to an applicant.
Several theories have been used to guide these regulations, but usually they are related
to the concept that reasonable and beneficial use of the water must be demonstrated by
those seeking a permit. Within the confines of an individual groundwater basin the
reasonable and beneficial tests are often modified when an increased amount of
withdrawal is permitted. More restrictions are placed on permits when it is perceived
that withdrawals are excessive and that undesirable impacts may occur if added
withdrawals are allowed. Restrictions to agricultural use for irrigation are particularly
notable because the amounts are large and it is often thought that this use is excessive
or wasteful. Irrigation systems are promoted that use less water but often without
much consideration about the effectiveness of these systems for plant growth and
development. Often the only reason for promoting those systems is for their reduced
demand on the groundwater supply. Similarly, restrictions to the withdrawal of
groundwater for public supply are imposed based on perceived damages but it is
difficult to find a supportable basis for equitably placing the restrictions.
Controls based on water level drawdown have been applied indirectly in the
past, particularly in the SouthWest Florida Water Management District by requiring
that a permitted withdrawal not cause water levels in the aquifer to be lowered by
more that five feet at the property boundary. This requirement served a useful
purpose but the amount of drawdown was essentially arbitrary. It apparently had its
base in little more than a subjective judgement that drawdowns greater than some
amount were not "fair" to adjacent property owners but there was no hard proof
extended that related such drawdowns to a definable damage.
Permitted withdrawals then were based on the concept that regionally there is a
quantity of withdrawal beyond which it is not wise to go because recharge rates would
not sustain additional withdrawal without a depletion of the supply in the total system.
It was assumed that sufficient recharge must be present equal to the amount of
withdrawal from the system or permanent damage will result. Regulations based on
this premise and its inherent assumptions do not ascribe a direct economic value to the
water nor the aquifer system that stores and transmits the water. The use and value of
the land overlying the aquifer is only indirectly influenced by the potential of the
groundwater system to provide water.
There are several shortcomings and disadvantages to this system of regulations.
Among these is the fact that the regulations tend to become more and more complex
as they attempt to overcome one after another technical shortcoming of a rule that has
an inadequate scientific basis or defensible rationale for application. Additionally it
places the regulatory agency in a the position of antagonizing the general public
because of perceived inequities in their permitting or restricting activities.
Enforcement of permit conditions and restrictions of the amounts of withdrawal are
difficult at best and gain little, if any, support from the regulated community. This
happens in part because they often see little connection between the restrictions and
the benefits they are supposed to achieve.
A regulatory permitting system that would overcome these shortcomings would
be useful and desirable. Such a system should be based on technical reasoning
broadly supported by the professional community, easily understood and applied by
the regulated community, and the benefits must be clear to the general public. In
addition such a system should allow for simple application and ease of detection of
offenders for enforcement. The purpose of this paper is to suggest the basis for such
a system and to discuss some of the implications for regulatory purposes.
The basis for this alternative system of ground water use regulations is that
water levels in the aquifer system should not be allowed to decline below established
levels: levels which must be maintained to limit the potential for saline water
encroachment laterally into the aquifer system and the potential for upward movement
of highly mineralized water to contaminate the aquifer. The levels must also limit
surface water impacts to lakes, streams and wetlands.
BASIS OF THE SYSTEM
The basic requirement and tenant of the matter suggested is that water levels in
the aquifer system can be determined that are the minimum levels acceptable to
prevent long term damage to the ground water supply. These levels can be derived
theoretically and supported by the existing data base describing water levels and water
quality. Obviously these levels change throughout the area and are influenced by
many factors. The changes in water levels relate to such factors as the distance from
the coast, the storage characteristics of the aquifer and its ability to transmit water.
The recharge characteristics off the area would also influence the determination of
optimum water levels throughout the region. Taking into account these factors, a map
could be produced that would depict minimum aquifer water levels throughout the
region. A system to monitor aquifer water levels and detect those areas where they
are approaching the minimum levels could be implemented and the results made
available to interested parties periodically. This approach could be technically
supported with major assumptions justified and open to examination and discussion
by the professional community. After complete and open examination of the technical
aspects involved it should receive widespread acceptance and agreement among the
professionals dealing with groundwater resources.
APPLICATION OF THE SYSTEM FOR REGULATIONS
One of the first implications of using this water level basis for regulations is
that there would be no restrictions on the amount of withdrawals. Any amount of
withdrawal could be make as long as the water level minimums were not violated.
Obviously some area will produce a much larger amount of groundwater than others,
making them much more desirable and increasing their economic value. This,
however, would only be one aspect of the overall value of the land similar to its value
for producing certain crops, or its value for housing because of aesthetics or
geographic location. The total value of the land would then take into account its
ability to provide water just as it would consider the lands other desirable and
undesirable traits. Land overlying aquifers that produce a large amount of water with
little drawdown would be more valuable for the purpose of water production and thus
the Water Management Agencies would be promoting development of land most
suitable for the purpose of producing water. Likewise, it would discourage
development in areas not desirable for groundwater supply development. In any event
the restriction on water levels would provide the basis for protecting the long term
viability of the area to procure water, a goal that should receive wide acceptance by
the general public and the regulated community.
Application of the general principals behind the system would be accomplished
by establishing a regulatory water level in each well for which an application was
submitted. The level would be based on the minimum water level in the area with an
allowance for well loss based on the size of the well. The level thus established
would be the maximum depth to which the pump intakes could be placed. The pump
installations would be made by individuals or companies licensed for this type of
activity and they would be required to certify that the installation met all regulatory
requirements including the depth of the pump intake. Spot checking of wells and
pump installations would provide a good and equitable method for regulatory
compliance verification and would take advantage of the well-drilling and pump
installation infrastructure already in place and licensed. Offenders to the permitted
levels, including both the landowner and the pump installer could be discouraged from
violations by a system of fines or license actions.
Several benefits could be realized by implementation of this system. It would
tend to be self regulating because it places a definable economic value on the
groundwater resource. This value would respond to the economic pressures of
supply and demand by making more valuable the land having the greatest capability to
produce more water without violating the water level standards. Since the levels
would be established and available to all there would be no confusion about the
application of the regulatory standards. The system would be based on the technical
concept of resource protection in a very definable and defensible way and for those
reasons should gain wide support.