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OCR for page 108
6
Conclusions and Recommendations
Groundwater is a vital national resource. Providing accurate and
timely information to manage and maintain the quantity and quality of
the nation's groundwater requires resource assessments and scientific
investigations across a variety of spatial and temporal scales. The U.S.
Geological Survey (USGS) is uniquely qualified to conduct and synthe-
size broad-based investigations. As outlined in an earlier review of the
National Water-Quality Assessment (NAWQA) Program (NBC, 1994),
the committee believes that regional and national synthesis of inforrna-
tion must be a key part of the USGS groundwater program.
The purpose of the regional- and national-scale groundwater investi-
gations envisioned in this report is to provide a framework for decision-
makers and a starting point for future site-specific studies by analyzing
hydrogeologic processes and conditions relevant to wide areas of the
United States. A general characteristic of regional investigations is that
they cover hundreds to thousands of square miles and usually extend
across state boundaries. However, beyond this commonality, the defini-
tion of a "region" varies with the specific problem being addressed.
Some regional investigations, such as studies of the High Plains aquifer,
may target hydrogeologically distinct, geographically contiguous areas.
Other regional studies, such as investigations of salt-water intrusion,
may focus on discontinuous but widespread areas, encompassing related
nonadjacent aquifer systems sharing common processes.
The committee has reviewed, and is in general agreement with, the
Strategic Directions for the U.S. Geological Survey Ground-Water Re-
sources Program (USGS, 1998~. This document proposes scientific
105
OCR for page 109
Conclusions and Recommendations
109
assessment of critical groundwater issues combined with a program of
regional and national overviews, access to groundwater data, and
research and methods development as key components for heightened
work on regional groundwater assessments. The following conclusions
and recommendations are intended to enhance this plan and address each
of the proposed priorities.
SCIENTIFIC ASSESSMENT OF CRITICAL
GROUNDWATER ISSUES
Conclusion: Policy-relevant regional and national assessments of the
sustainability of groundwater supplies under current and projected pat-
terns of groundwater use are essential for Tong-term resource-
management decisions. Assessments of sustainability represent the
synthesis of resource inventory and characterization, process studies,
problem identification, and decision support. The recently published
circular Sustainability of Ground Water Resources (Alley et al., 1999)
shows the wide range of these interlocking issues. The broad topic of
sustainability includes the interaction of management decisions (e.g.,
pumping rates, conjunctive use of groundwater and surface water), re-
source dynamics (e.g., climatic change, recharge rates), environmental
impacts (e.g., streamflow depletion, water quality degradation), and
emerging technologies (e.g., aquifer storage and recovery projects).
Conclusion: Within the overarching theme of sustainability, the com-
mittee recommends that the following groundwater issues be given the
OCR for page 110
110
Investigating Groundwater Systems
highest priority for investigation by the USGS in the context of regional
and national studies. Each issue is relevant over large geographic areas
of the United States, has implications for water-management decisions,
and raises significant questions best addressed through Tong-term scien-
tific research.
· Aquifer management: optimizing groundwater extraction while
limiting undesirable effects such as salt-water intrusion, land subsidence,
and harm to ecosystems,
Aquifer storage and recovery (ASR) projects: use of aquifers for
repeated storage and recovery of water of varying quality,
Groundwater recharge: quantifying rates, spatial locations, and
mechanisms of recharge from local to regional scales,
· Surficial aquifers: evaluating hydrogeology, water-level
changes, and water quality changes,
Interaction of groundlwater with surface water: researching pro-
cesses and mechanisms in wetlands, rivers, lakes, and coastal areas,
o Flow and transport in karst and fractured aquifers: under-
standing pathways, identifying recharge areas, and characterizing prop-
erties at different scales, and
Characterization of heterogeneous aquifers at large and small
scales: understanding links between geology and hydrogeology, and
developing new characterization methodologies.
REGIONAL. AND NATIONAL OVERVIEWS
Conclusion: A regional and national synthesis effort in the USGS
groundwater program must be integrated with other programs to be suc-
cessful. The current 2 percent of the USGS Water Resources Division
(WRD) budget allocated to the groundwater resources program is insuf-
OCR for page 111
Conclusions and Recommendations
111
Ancient to do much more than identify project areas, coordinate projects,
and disseminate information. A meaningful national groundwater pro-
gram must therefore take advantage of many WRD resources, including
the Federal-State Cooperative Water (Coop), National Research, Toxic
Substances Hydrology, and NAWQA Programs, and other relevant ac-
tivities. Studies will necessarily be interdisciplinary. They will likely
involve collaborative work with scientists from other divisions of the
USGS. Many of the studies will be of such scope and complexity that
expertise from outside the USGS may be required. Partnerships with
other federal or state science agencies and with research universities
through the Water Resources Institutes would likely prove advantageous.
Conclusion: The USGS needs a clear administrative method for setting
priorities and choosing issues and regions for study in the context of na-
tional synthesis. The current decision process is not clear to the com-
mittee, and it may not be understood by many USGS district staff. Many
issues and regions of the United States are appropriate for study, but in
an era of limited resources, the USGS needs to make difficult choices in
allocating resources to some issues and regions over others. The frame-
work for making these decisions is not addressed in the current WRD
StrategicPlan(USGS,1999c). In addition, there is a need for improved
coordination of research efforts and data collection with federal, state,
local, and private organizations outside the USGS and with universities
and state geological surveys as well.
OCR for page 112
112
Investigating Groundwater Systems
ACCESS TO GROUNDWATER INFORMATION
Conclusion: Regional groundwater investigations have the comple-
mentary goals of developing new scientific knowledge and translating
that knowledge into information relevant for decision-making and policy
for~nulation at regional and national levels. The proposed National Aq-
uifer Database, with availability over the Internet, is one mechanism for
making study results widely available. However, this database alone
will not fill the need for synthesis of the scientific findings; instead, it
will provide support and documentation for those findings. The synthe-
OCR for page 113
Conclusions and Recommendations
~3
sis and the interpretation of findings need to occur on two levels: (~)
technical scientific summaries of research findings and (2) interpretive
summary and synthesis publications aimed at providing information to
decision-makers.
Conclusion: As building blocks for national synthesis, most of the pri-
ority issues outlined in this report will require many studies over many
years. Consequently, data management is a critical part of the regionali-
zation effort, especially in an era of rapidly changing data-management
and storage technologies.
Conclusion: Now, and in the future, the USGS will be expected to
maintain and make available both primary and interpretive groundwater
data in digital formats. With the existing USGS Internet sites and such
electronic platforms as the National Atias of the United States, the main
elements for a web-based data and metadata delivery system are already
in place.
OCR for page 114
114
Investigating Groundwater Systems
Conclusion: There is an ongoing need for expert interpretation and ex-
planation of groundwater information at the local level. The integration
of place-based groundwater studies into regional investigations must
ultimately produce information and implications relevant to local water
managers and individual citizens. These interpretations are often best
provided by individual scientists familiar with the local issues and with
local hydrogeology.
METHODS DEVELOPMENT
Conclusion: Physically based process models are essential for region-
alization of groundwater information. Understanding physical proc-
esses, the variations in parameters controlling those processes, and the
uncertainty of predictions is essential for investigating groundwater sys-
tems at regional scales. The USGS expertise in model development is
well known. Recent advances in model visualization, links to GIS, pa-
rameter estimation, uncertainty modeling, and optimization provide
powerful new tools to the hydrogeologist.
OCR for page 115
Conclusions and Recommendations
~5
Conclusion: One of the most fruitful methods of regionalization and
synthesis may be increased emphasis on the links between geology and
hydrogeology (e.g., Leahy and Lyttle, 1998~. Geology exerts a funda-
mental control on hydrogeologic processes, and regional variations in
geologic setting offer an obvious starting point for regional groundwater
studies.
Representative terms from entire chapter:
groundwater issues
