The workshop began with a series of very brief presentations by representatives
of the various geographic areas represented at the meeting. These presentations
were designed to highlight the particular concerns of the different regions
and to provide a perspective for the ensuing discussions.
Ricardo Alvarez on the Southeast and Islands:
The water's edge
defines where things happen, like extreme events. Some of the region (i.e.,
the southeastern states) has abundant water; but some (e.g., the Caribbean
Islands) has no groundwater. Policy in water management is, therefore,
critical because management competes with development. Demographics plays
an important role in water management and use in this area because of
the high population densities along the coast and because of large seasonal
swings in population. Some health hazards are associated with water resources.
And recent events have proven that both drought and increased precipitation
need to be dealt with.
Nani Bhowmik on the Eastern Midwest:
The eastern Midwest includes
some of the largest river systems in the nation and is heavily affected
by drought and flood. Drought brings on low flow and depletion of groundwater.
Flooding produces crop and property damage, erosion, and sedimentation.
In addition, agricultural runoff from the region is causing hypoxyation
of the Gulf of Mexico. On the bright side, floods increase the fish population.
Generally, the region has plenty of water, but the effectiveness of the
distribution systems varies, and because of that, some areas will go without
water during droughts.
Frank Quinn on the Great Lakes:
The Great Lakes, while making
up 95% of the fresh surface water in the United States, are a shared resource
with Canada. The degradation of the water quantity, quality, associated
ecosystems, and coastline is a problem. Water management (the lakes are
managed) also has problems. Anticipated problems associated with climate
change and variability include increased air temperatures, changes in
precipitation, more evaporation of lakes, increased evapotranspiration,
decreased tributary flows, decreased net water supplies, and lower lake
levels with three times the normal variability of water level in the lakes.
What is needed is a serious consideration of sustainability, the development
of a robust water-management plan, the addressing of groundwater supplies,
and an assessment of water-quality and ecosystem impacts on the 121 watersheds
around the Great Lakes.
Kathleen Miller on the Central Great Plains:
The main transbasin
diversions are the tunnels drilled through the Rockies to bring Colorado
River water to the Central Basin. Irrigated agriculture is a main end
use and is increasing, although there is some transformation from agriculture
to urban development. The biggest issue is the tightly allocated water
supplies. An example of this tight allocation is the Arkansas River, which
serves multiple uses as it goes through the different states. This tight
allocation of the Arkansas' waters has led to a number of lawsuits regarding
groundwater as well as surface-water issues.
Dave Penn on Hawaii-Pacific:
The Hawaii-Pacific region covers
a vast expanse of ocean, but has a small population that is scattered
in geographically isolated, culturally and politically diverse, and economically
and ecologically vulnerable communities. Water resource systems occur
on (1) low-lying atolls whose groundwater bodies are very small and fragile
and (2) high islands with larger, more resilient aquifers where runoff
from the mountains is also used as a water resource. Extant general circulation
models for climate prediction do not yet provide strong results for Hawaii-Pacific
region conditions; instead, ENSO characteristics are used as a model for
expected climate change. Research and information needs include: upgrading
and expanding basic data collection efforts, gaining more thorough knowledge
of climate-system processes, conducting education and information campaigns,
and enlarging industrial sector involvement. There are critical water
management issues to be addressed as well, including many affecting our
populations of native Hawaiians and other native peoples.
Upton Hatch on the Southeast:
The southeast regional workshop
identified agriculture, forestry, and ecological systems as the main areas
of concern in regard to water. To assess what climate change and variability
might do to those resources, institutions and agencies are performing
climate-model simulations and biophysical-response models for agriculture,
forests, and land use.
Brent Yarnell on the Middle Atlantic States:
An upward trend in
precipitation and productivity is currently evident for the region. It
had some severe drought produced during the past few decades, and winter
storms and hurricanes produced flooding. The Middle Atlantic region can
therefore be best characterized as an area with great variability and
large vulnerabilities. It has a lot of metropolitan areas that are sensitive
to climate variation. A large portion of the population gets water from
private wells. Those small systems are highly sensitive to climate variability.
As a result, emergency water management is a major issue here.
Con Baldwin on the Rocky Mountains/Great Basin:
of the region to the effects of climate change and variability was investigated
with runs on GCMs. The results of these simulations pointed out a number
of important trends resulting from land-use change and changes in demographics.
The models also showed correlations between climate changes and historic
Blair Henry on the Pacific Northwest:
As temperatures go up, snowpacks
in the mountains go down, and those snowpacks feed most of the area with
its water resources, all east of the Cascades. Late fall snow turns into
flood-producing rains under a warmer climate, and less water flow results
during the summer. The Columbia River already has too many demands on
too little water. One of the big issues is how long it takes fish to get
downriver with all the reservoirs in place. At the same time, the river
flow is going to happen earlier; the life cycles of the fish will not
correspond with the earlier runoff produced by warmer climate. In addition
to all this, the habitat of the fish is being degraded.
Jurgen Schwandt on the Rio Grande:
No place in this region has
enough water. All places are experiencing rapid urban and population growth.
Conflicts are arising between Indian tribes and the rest of the community.
Only on the U.S.-Mexican_154" value="Mexican, Uzbekistan, Admixing, Sixgun, Execking" /> border has an analysis been performed on climate-change
effects. That analysis indicates that the droughts that the region has
been experiencing will increase and tropical diseases will increase. With
the population doubling every 20 years, aquifers are being depleted rapidly;
border river water is being allocated to agriculture. In fact, agriculture
is thriving, and no drought-management plan is in place. The answer to
supply problems is increased efficiency of agricultural use. With water
down to 20% of its historical levels, the biggest threat is to the ecology
of the region. But the legal differences are very difficult to overcome.
David Major on the Metro East:
The area has many water-supply
systems, but they are dominated by New York City. Water supply is a dynamic
system linked to many other systems. Climate change could occur on top
of these other dynamics. The effects of climate change on the water system
are unknown. Rising seal level will invade the Long Island aquifer, producing
an increased demand on the New York City system. New institutional forms
and changes will be needed as will new infrastructure systems. The quality
of effluent waters has improved radically, and these will not be affected
by climate change unless large increases occur in upstate precipitation
and there is a large sea-level rise.
Jerry Fletcher on the Appalachians:
Modeling efforts are trying
to see if the large increases in precipitation over the mountainous areas
Geographic Breakout Sessions
The workshop participants then broke up into smaller groups to discuss
and prioritize the concerns of five major regions: the Northeast, Southeast
and islands, Central Plains and Midwest, West, and Pacific Northwest.
The breakout groups were to consider the stresses that the area was currently
undergoing, the information that was needed to assess and cope with climate
change and variability in the area, and potential response strategies
for the stresses and problems anticipated. Afterward, the moderators and
rapporteurs summarized their group's findings.
The issues that people want discussed relative to water
in the northeast states are:
Existing water-management plans are not robust enough to respond
if climate changes are outside the range of recent experience (that
is to say, the past few decades). An example cited was that the water
supply systems in the Great Lakes are adapted to recent, relatively
high lake levels, but will be in trouble if lake levels return to the
lower levels that have been experienced in earlier centuries. We need
reliable simulations that can tell us what will happen to the levels
of the Great Lakes.
We do not understand the sensitivity, vulnerability, or adaptability
of all socioeconomic groups; this aspect should be studied now if we
are to avoid surprises in the future. Penn State is designing a survey
to find out what those stakeholders' concerns are.
Water-management organizations are not adequately aware of what we
do know about climate variability and change, and they are not using
the best available information in their planning. The example cited
was the lack of incorporation of sea-level changes into navigational
improvements in harbors.
The overlapping and redundant nature of federal and state water-management
agencies is a real problem in adapting to climate change. Coordination
and communication are seriously lacking, and that aggravates the vulnerability
of water systems and undercuts opportunities to establish cooperative
commissions and other institutions. A counterexample is the success
of river-basin commissions, such as the Delaware River Basin Commission.
We need more of these interagency or superagency entities.
We need to better understand the extremes of current climate; what
had been considered 100-year floods are occurring more frequently than
The Water Sector assessment must look at international water issues
along the U.S. borders with Canada and Mexico.
Changing values and expectations are a serious challenge to water-management
systems. Climate change will aggravate this already difficult situation.
The recurring example here is the flow needs required for environmental
purposes being added to fully allocated water systems. The way to adapt
is to develop more flexible institutions.
Southeast and Islands:
The major stress is water availability.
Water management and storage techniques cannot keep up with the demands
of the increasing population (which strains supplies, degrades water quality,
and places great burdens on wastewater-treatment facilities), the vagaries
of demographics (temporary populations build up and then go away), and
the competitive needs of maintaining aquatic habitats and agriculture
(which not only consumes water but also produces contaminated runoff).
Secondary stresses include saltwater intrusion, subsidence as water is
withdrawn from the subsoil, economic globalization of agriculture (foreign
competitors produce demand for increased domestic productivity; climate
effects on Mexican agriculture are more influential on Florida agriculture
than the Florida climate is), and extreme events (such as hurricanes and
droughts). As a result, water resources are so strained that marginal
changes could have major effects. To deal with these stresses, we need
a more-responsive form of water management that has the flexibility needed
to cope with climate change. As the stresses are addressed, we need to
monitor the response strategies to see what works and what does not, we
need to review policies for currency, and we need to spend more money
on such things as rainfall collectors and to check to see how well that
money is spent. The information needed to accomplish these tasks includes
flood maps (from FEMA), flow plans, weather forecasting, and fuller assessments
of current stresses (land use, demographics, and population) that reveal
how those stresses change with time.
Central Plains and Midwest:
The current stresses observed in the
Central Plains and Midwest are evaporative losses of water resources,
land-use patterns in the Mississippi basin, overdrafting of the Ogallala
Aquifer, interstate policy conflicts, water quality, and the increasing
desire to meet environmental-quality standards. To address these concerns,
we need better hydrologic models, river-flow sensors, flood and drought
statistics, a better understanding of human responses to environmental
and social changes, a baseline understanding of how the world would change
without climate change, data on land-use change, a survey of water scarcity
in the Midwest states, an assessment of how groundwater changes under
stress, and better confidence in short-term climate predictions. Potential
response strategies for addressing these stresses include recharge technologies,
water banking, conjunctive water use, greater consolidation of water-supply
systems, and land management that will increase the water-holding capacity
of the soil and subsoil. Information systems that would help achieve these
objectives include HUMUS (Hydrologic Unit Model for the United States),
downscaled and disaggregated water-use data, and extant but unused satellite
West: Increasing population is decreasing the water supply and quality at
the same time that international problems are putting demands on available
supplies. The information needed to address these concerns includes knowledge
of the likely outcomes of climate change in terms of flood, drought, and
snowpack; improved collection of streamflow and water-quality data; information
on convective storms, glacial advance and retreat, and models' limitations.
Responses that might alleviate the stresses include conservation, reuse,
recharge, the integration of land-use planning with water-supply planning,
regulatory reform, and a negotiated settlement of Indian water rights. Current
research that will shed some light on these problems includes the intercomparisons
of GCMs (such as AMIP), studies of hydrologic sensitivity, research on the
effects of sea-level rise on the lower Sacramento and San Joaquin basins,
snowpack-runoff studies, and the evaluation of socioeconomic studies on
The water-use issues vary widely throughout
the region, depending on geography and climate. East of the Cascades,
irrigation is a major use, and the availability of water for that purpose
is very important, and hydropower is considered a competing use. Dryland
agriculturists, however, are more interested in temperature changes and
their effects. West of the Cascades, a 50% increase in population is expected
in the coming decades. As a result, the low storage capacity will need
to be increased. That increased capture of runoff will be important because
the groundwater is already being drawn down and polluted. In Alaska, the
major concern is loss of the permafrost south of the Yukon River, resulting
not only in the loss of natural resources but also in damage to the area's
infrastructure (buildings, roads, bridges, power lines, etc.). Some socioeconomic
issues are surfacing in response to these stresses, such as the pitting
the survival of endangered species against economic development and other
transforming land uses. Models are playing a major role in defining the
problems and suggesting solutions to them. But concerns exist about the
different results obtained from different models. We need to determine
the sensitivities of these models to prescribed changes; this is especially
true for hydrologic models. The models also need to be downscaled to provide
information on a regional basis. To improve the resolution and reliability
of these models, more data sets need to be compiled, different types of
models need to be developed (reservoir models, for example, need to reflect
all of the influences that act on reservoirs), and regulators need to
be involved early in the process of modeling systems and changes and prescribing
Topical Breakout Sessions
Later, the workshop participants broke up into small groups to discuss
and prioritize the concerns related to five major water-related topics:
extreme events, human health, water management, water use: quality and
availability, and aquatic ecosystems. The breakout groups were to consider
the vulnerabilities observed, the concerns that needed to be dealt with,
coping strategies that might be applied to ameliorate the concerns, and
the knowledge gaps that have been identified as hindering the implementation
of these strategies. Afterward, the moderators and rapporteurs summarized
their group's findings. Extreme Events: We need to understand trends in
streamflow, humidity, and water quality and variability over time. We
also need additional information about trends in floods and droughts,
especially what part human intervention (e.g., development) has played
in influencing those trends. A particularly interesting question is whether
the hydrologic system has intensified. Little work has been done on a
number of important topics, such as orographic precipitation and urban
effects on extreme events. On the other hand, masses of historical weather
data are available awaiting analysis for long- and short-term variability.
Islands and coastlines need to be studied not only because of their vulnerability
but also because they are too small to be resolved by GCMs.
Several response strategies should be adopted. In the short term, the
deletion of stream gages needs to be reversed. In fact, we need improved
monitoring networks and forecasting; these improvements should be accompanied
by education about the application of forecasts. Similarly, the results
of the current assessments should be made available to the public, policymakers,
and industry. The public should be educated about the connections between
climate change and extreme events. And policies and laws should be reevaluated
after extreme events to see how changes could minimize effects and prevent
losses. An assessment of the availability of insurance coverages is also
needed. Some of these strategies could be initiated at the upcoming AWRA
meeting. A special task that should be undertaken is a literature review
of past events and a description of trends. Likewise, the various GCMs
should be described along with evaluations of their applicability.
A general recommendation put forward is that all segments of the National
Assessment must share data and communicate their findings with the public.
Even though the United States has good water-treatment
and other sanitary facilities, it still has sporadic outbreaks of waterborne
diseases. It is instructive to look at where the vulnerabilities are:
Coastal areas and agriculturally intensive watersheds are especially vulnerable.
Small systems are also vulnerable because of limited monitoring and prescriptive
management; moreover, 20% of the U.S. population gets its water from private
wells. Much data has been collected but needs to be used more widely,
such as the American Water Works Association demographic trends in water
demand, the USGS water-use data, the USGS streamflows and watershed maps,
USDA agricultural data, and NOAA marine data.
The water and health concerns specifically related to climate change
are variability (floods and droughts produce microbes and toxins), timing
(e.g., the early melting of snowpack can lead to flooding, limiting later
availability), and distribution. A major need for addressing these concerns
is the development of more and better hydrologic models.
The best solution for coping with these problems is water treatment;
the barrier here is money. Also effective would be watershed protection,
effective transport (here state water rights are barriers), and upgraded
building codes and zoning to protect against floods and mudslides. Knowledge
gaps that need to be filled in to bring about these solutions include
the lack of long-term data and the barrier of data confidentiality.
The deficiencies in the current water-management
system include the lack of a basin-wide approach being used uniformly
across the landscape, available information and technology not being used,
and the lack of flood- and drought-management plans in most regions. The
consensus of the breakout group was that, if you have adequate institutions
to deal with extreme events, you will probably be able to handle climate
Several institutional reforms need to be made. The size of a water-management
organization should be based on the size of the watershed. The need for
cooperative agreements among parties must be reflected in state laws,
federal compacts, and international agreements. Information must be synthesized
for the end user. Currently, socioeconomic costs are not integrated into
management; in fact, we do not even know what all the tradeoffs would
be, and institutions do not exist to incorporate this information into
Water management needs a summarization of what works and does not work.
Also, current flood responses are fragmented; the players need to be brought
Quality and Availability: Impact assessment is the
measurement of the deviation from some baseline. Water availability can
be assessed from a demand-side or a supply-side perspective. The demand-side
standard could be a status-quo response or a changing-society viewpoint.
In the former, per capita water use would not increase in the future,
and population projections would determine water needs. In the latter,
new technologies, policies, and laws would likely come into play to drive
down the per capita demand to an equilibrium level. With a supply-side
approach, output from GCMs and/or HUMUS would be used to prescribe what
the available water will be. Also. the Environmental Protection Agency
is developing vulnerability indexes. Such indexes could be developed on
the community, watershed, county, or larger basis. With these tools, the
needs and shortfalls of the future water supply can be calculated.
The absence of ecosystem interest is problematic
and indicative of the fact that we do not have a balanced mix of representation
yet. The following are the main points that were emphasized:
Ecosystem values are an emerging issue that must be accounted for
in water-resources management. A typical example cited was the fact
that fish management has moved from the third or fourth priority to
the No. 1 priority in the Columbia River basin recently.
Ecosystem integrity is the linchpin that integrates multiple-use
water-resources management. If ecosystem water needs are ignored,
overall water-resources-management risks are increased and vice
There is insufficient understanding (scientific knowledge) to
define the sensitivity of aquatic ecosystems to climate variables
and their response to climate change. Moreover, fish are not the
only endpoint; geomorphology and riverine flow regimes must also
be taken into consideration. In addition, we need to recognize that
recreational uses of water are increasing, and we need to quantify
that use at national scales.
We will make a start at synthesizing what is known in the Water
Sector Assessment Team (WSAT) white paper on ecosystem response
(Meyer, Sale, Mulholland, and Poff, in prep.).
In managed systems especially, we need mechanistic-response information
relating ecosystem values and flow/climate so that tradeoffs in
water-resources management can be evaluated. Ecosystem flow needs
should be studied across different systems and at different trophic
In natural systems that warrant protection, it may be feasible
to define response thresholds for management purposes.
Fluvial geomorphology and riparian systems are too often ignored,
and they are important. Climatic effects include changes in flood frequency
and intensity and in nutrient cycling.
Indirect effects of climate change may have significant influence
on future species distribution, such as competitive interactions with
exotic or introduced species. An example here is the introduced crabs
that are moving up the west coast in response to thermal changes.
We should design a specific session at the Atlanta conference of
the American Water Resources Association on the topic of aquatic-ecosystem
response to climate; it will provide a peer-reviewed test of ideas.
GCM output and regional assessment can be used to identify areas
at risk to climate change. Two examples cited are:
EPA's upcoming study on Water and Climate: A National Assessment
of Regional Vulnerability (Hagler Bailly Services, in prep.).
Gaps, Collaborations, and Links
After the breakout-session reports, a roundtable discussion was held
to identify gaps, collaborations, and links. This session was an opportunity
for participants to bring forward ideas for further action, to flag subjects
that need investigation, and to point out research that has been done
and that could contribute to the understanding of problems brought forth
during the workshop. The discussions were generally grouped around relevant
topics or leading questions. The following observations, comments, questions,
and suggestions were raised.
How do you integrate the water sector to the other parts of the assessment?
Norm Rosenberg's model might set a small part of the stage that will
show what climate change will mean. We will put together measures of
vulnerability, but how to integrate the regional and sectoral assessments
is still undecided.
Groundwater: Not a lot of research is being done on groundwater.
The current models are not adequate for determining recharge. We should
determine where large concentrations of population rely on groundwater,
where overdraft is much greater than recharge, and where groundwater
makes up shortfalls in surface-water. In answering these questions,
we must remember that reliance is not just for municipal drinking water
but also for agriculture and industry. Such questions as "What would
a decrease in irrigation do to agricultural productivity?" must be addressed
along with "Will we always find money to subsidize people to produce
Saltwater intrusion: Consensus should be sought among water managers
about the effects of saltwater intrusion: Should such waters be made
available to make up for surface-water shortfalls? If so, what quality
(brackishness) limits should be imposed? And is desalination an option
that should be considered?
Reducing demand: Municipal water systems have shown a large flexibility
(elasticity) in making up for shortages. If you run out of conservation
measures, you can go to conjunctive use. The current (and recurrent)
requirements exceed any that might be brought about by climate change.
Sea-level rise: The big issue related to sea-level rise is the contamination
of sea-level aquifers. We could use a map of aquifers that are vulnerable
to salt-water invasion. Land-inundation mapping has been done, but only
pieces of the aquifer mapping have been completed. The Corps of Engineers
has looked at salt-front (or salt-wedge, 250 ppm) advancement up estuaries,
but that process would be altered by climate change. Peter Shanahan
has proposed such an effort to EPA. The Office of Groundwater of the
USGS has been identifying aquifers that are vulnerable to salt-water
intrusion. The process is two-edged:
Ecosystems can be created or destroyed by salt-water intrusion.
Sea-level rise could also produce a backup of sewage in disposal
systems and the general hampering of sewage-disposal systems.
Extreme events: The workshop did not take up the topic of the effects
of droughts and floods on agricultural productivity; extreme events
are very important to the agricultural sector. The insurance industry
is interested in climate-change effects on extreme events. It would
be helpful if we had measures of extreme events so that we could express
climate-change effects in terms of extreme events. Already, sewage overflow
during extreme events is having effects on water quality in large and
small cities. We need data on runoff during extreme events to determine
the introduction of disease organisms into surface waters. We also need
to connect the GCMs to extreme events; one way would be through the
use of 300-mbar data, which indicate the amount of energy available
for storm formation and sustenance.
Ecosystems: A question that needs to be clarified and answered is,
"Should in-stream flows be guaranteed to maintain (or restore) the ecosystem?"
This topic is coming to the forefront as the impact of water management
on endangered species is publicly questioned. Changes in vegetation
will also have effects on an ecosystem. These questions are specific
issues within the more general framework of the impact of hydrology
on the riparian system and the follow-on effects on the surrounding
ecosystem that are very important. In all considerations of the interplay
between water and ecosystems, one must realize that ecosystems compete
with other land uses that require water resources. Gaps in knowledge
about ecosystems and their health should be cyclically analyzed. In
considering ecosystems, the water-sector researchers could provide information
to the coastal sector on freshwater inflows to estuarine ecosystems.
In all ecosystem research, the Second National Water Assessment data
could be used as a baseline. Another good source of data is Diane Knight's
workshop, which has been published in Hydrologic Processes. Definitive
descriptions of ecosystems are needed so that the health of a specific
ecosystem can be gauged. A topic that was not brought up at the workshop
is the change in ecosystems brought about by invasive, exotic, or introduced
species and the prospects for restoration of an ecosystem to its original
Future scenarios: We are going to develop a number of future scenarios
for demand and supply of water.
Legal issues: We should produce a writeup about the legal issues
surrounding water resources and use at the local, state, national, and
international levels. We need to identify some of the stress points
that we are likely to encounter with climate change and that would lead
to legal contentions (e.g., the changing of the terms of water-allocation
compacts with the change of precipitation regimes). A more far-reaching
inquiry would be whether the water-appropriation system in the West
is changing and what the legal landscape might look like in 20 years.
Water management and coping: A large number of strategies for coping
with climate change are available. A good way of approaching the problem
would be to ask, "What stresses would we expect in the future without
climate change, and how will they change the nature of society?" Then
we could add climate-change stresses and ask whether the strategies
already adopted would be adequate to cope with the added stresses. A
major question to be investigated is if it is plausible that climate
change will produce situations that cannot be managed. Another is what
we can do to bring useful information to water managers.