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Introduction
Awareness of global,
regional, and local water trends can ensure that organizations
have time to plan and act before crises arise. This section
presents several important water trends.
- Although most
of the world is not running out of freshwater, a number
of regions face chronic freshwater shortages
- In the future, water shortages are likely
to spread due to increasing demands, unsustainable withdrawal
rates, difficulty in finding new supplies, pollution and
source water contamination, and changing climatic and precipitation
patterns
- Water shortages impact regional security
by causing human health problems and population displacement,
increasing conflicts between competing users, and damaging
ecosystem health
- While regulatory responses are becoming
more stringent, watershed-based management approaches are
expanding
Freshwater
Supply, Quality, and Availability Trends
The world is not
running out of freshwater resources, but freshwater is not
uniformly distributed. A number of regions are experiencing
chronic freshwater shortages.
Less than one percent
of the world’s freshwater is readily accessible and located
in the lakes, rivers and streams that cross our continents.(1)
Although freshwater is a finite resource, the world’s
water cycle is constantly renewing itself. Rain and snow supply
enough new water every year to inundate all of Europe under
almost seven feet of water.(2)
But freshwater resources are not uniformly distributed, and
many regions are suffering from shortages.
The Middle East, North Africa and the Southwestern
U.S., among other regions, have long been familiar with water
shortages. Increasingly, shortages are occurring even in places
that have access to relatively large amounts of water. China
is facing severe surface and groundwater supply problems as
it irrigates croplands to feed its enormous population. The
Ganges River in India and the Chao Phraya River in Thailand,
both of which are in monsoon regions, now experience times
in the year when little or no water reaches the ocean.(3)
The Pacific Northwest of the U.S., well known for its wet
weather, and states from Maine to Georgia have recently experienced
several summers of drought.(4)
The severity of water shortages varies greatly
from place to place. Some areas face issues such as hydroelectric
power shortages, decreased crop yields, and loss of species
habitat, while some less developed nations confront the true
crisis of insufficient water for basic human needs. Despite
this range of differences, an important commonality is emerging
in all global water resource issues. Shortages and conflicts
are less the result of insufficient technological or infrastructure
capacity for accessing new sources and more a result of water
demands surpassing the availability of local freshwater resources.
Increasing human demands for water and unsustainable rates
of water withdrawal are likely to worsen water shortages.
Other factors also have the potential to affect long-term
water availability.
40% of the world will live in water-scarce
regions by 2025.(5)
Factors likely to contribute to these predicted water shortages
include population growth and unsustainable rates of water
withdrawal. The United Nations currently estimates global
annual population growth at 1.2%, which translates to an increase
of 77 million people per year.(6)
Current data indicates that 10% of the global
agricultural harvest—180 million tons of grain—is
produced by depleting groundwater supplies.(7)
Extensive surfacewater withdrawals for irrigation have also
contributed to the dramatic shrinking of some of the world’s
great freshwater bodies including the Aral Sea and Lake Chad.
Given that agricultural irrigation is the world’s largest
use of freshwater, accounting for twice as much as the industrial
and domestic sectors combined, these unsustainable rates of
withdrawal have already caused water shortages and will likely
cause more.
Some researchers have identified potential
linkages between changes in the earth’s climate and water
availability. This research suggests that changing precipitation
patterns could lead to possible disruptions of traditional
weather and run-off patterns and affect regional water supplies.
Changing temperatures could also decrease the storage and
subsequent slow release of moisture from snow and ice.(8)
Pollution of existing freshwater supplies exacerbates water
constraints and shortages. At the same time, water management
advances are providing water quality and availability improvements.
Surfacewater and groundwater pollution effectively
decreases the quantity of usable freshwater. Many of the world’s
lakes, large rivers, and most of its estuaries have been contaminated
with industrial, municipal, and agricultural runoff and effluent
discharges. Contamination of surfacewater has led many regions
of the world to turn to groundwater. While most of the planet’s
groundwater remains pure (largely a result of the fact that
there is almost 100 times as much freshwater underground than
there is on the earth’s surface), contaminants such as
pesticides, nitrogen, petrochemicals, radioactive waste, and
a variety of heavy metals increasingly threaten these supplies.(9)
The pollution of groundwater aquifers is not just significant
for localized groundwater users but also for surfacewater
users since the base flow for major rivers such as the Mississippi,
Niger, and Yangtze comes from groundwater sources.(10)
Significant progress has been made in developing
technologies and best practices for conserving, purifying,
recycling, and desalinating water, all actions that effectively
increase freshwater availability. In the developed world,
basic efficiency measures are now widely practiced in the
industrial and commercial sectors and include the use of low-volume
plumbing fixtures, reduction of irrigation schedules, and
efficiency improvements for water-cooling technologies and
equipment. Industrial dischargers generally employ best available
pollution control technologies. Basic drinking water and sewage
treatment are in place throughout the developed world and
some developing nations. More efficient and effective technologies
are gradually emerging.
While desalination is not yet cheap enough
to be broadly applicable, the technology has advanced significantly,
most notably in the technique of reverse osmosis (RO), which
uses pressure and semi-permeable membranes to filter salt
or other contaminants from water. The effectiveness of RO
has increased, as has the durability and dependability of
membranes used in the process.
Many areas of the world are taking advantage
of improvements in wastewater reuse and reclamation technology.
In Singapore, recycled and reclaimed water is emerging as
an essential alternative to water from the mainland. By 2010,
the island country aims to meet 20% of its water needs through
reclaimed water. A new water treatment facility will have
the capacity to produce “Newater” (a term coined
by the Singapore Utilities Board), reclaimed water with an
even higher purity than the standard potable supply.(11)
In arid Namibia, wastewater-recycling technology has helped
meet water needs in the capitol city of Windhoek at less than
half the cost of developing new sources of supply.(12)
Expansion of freshwater supplies is increasingly costly and
controversial.
In the past, as demand for water has increased,
society’s focus has been on addressing this demand through
increases in supply. However, this solution is becoming
increasingly difficult and costly and may soon be infeasible
in many areas.
No longer does the drilling of additional
wells sufficiently address agricultural supply issues. The
area of irrigated land using water from the Ogallala Aquifer
in the Western U.S. has decreased since the 1970s because
of falling water tables and rising pumping costs.(13)
While advanced desalination technologies have been implemented
in some energy rich, water poor areas of the world such as
the Middle East, overall costs remain prohibitively high in
most places due to the large amounts of energy and capital
required.
Large diversion and storage projects are
also increasing in cost and decreasing in feasibility, especially
as ecological and social costs are considered. China has long
proposed the diversion of its southern rivers, such as the
Yangtze, to the country’s northern plains to satisfy
increasing demand for irrigation water. However, the potential
financial, social, and environmental costs of the project
have made it very controversial. In 1991, Libya completed
a $25 billion water diversion project that pipes water from
desert aquifers to the coastal population centers, but these
types of projects are unlikely to solve growing freshwater
supply problems.(14)
Social
and Environmental Dimensions of Water Issues
Inadequate supplies
of clean freshwater contribute to a broad range of public
health issues, especially in the non-industrial nations and
some developing nations.
Human health can
be affected by freshwater problems ranging from contamination
of municipal water supply sources to pollution of water bodies
used for fishing or recreation. Pathogens that cause acute
illness and disease, or chemicals that can be carcinogens
in high concentrations, can affect drinking water supplies.
Non-industrial and developing nations face the most serious
threats to human health from inadequate freshwater supplies.
Various sources estimate that 1 to 1.5 billion people lack
access to safe drinking water, 2 to 3 billion people lack
access to proper sanitation, and 14,000 to 30,000 people die
each day from water-borne illnesses.(15)
These astonishing numbers represent a significant challenge
for individuals, governments, and businesses in coming decades.
Drought, freshwater depletion, and floods contribute to population
displacement.
Freshwater shortages, and attempts to address
them through diversion and storage projects, have displaced
large numbers of people. As lakes and rivers dry, people dependent
on these resources are forced to move. Experts estimate that
dams displaced 40 million people in the 20th century. Official
records show that at least 10 million were displaced between
1960 and 1990 in China alone.(16)
Floods have also contributed to significant population displacement
around the globe.
Water scarcity is increasingly leading to conflict, especially
in arid areas.
Violent conflict over water resources has
occurred in many regions of the world, most notably in the
Middle East where scarce water resources exacerbate existing
religious and political tensions. Other examples of recent
violent disputes over water include a Brazilian invasion of
a contested dam site in Paraguay, irrigation rights disputes
in India, military protection of dam construction in Slovakia,
and violent water shortage protests in Bangladesh. Other examples
exist of non-violent water-related conflicts that have produced
protests, national and international stand-offs, and contentious
debates.(17)
Even in places where water scarcity has
not escalated to a cause for conflict, there is increasing
public concern over water quality and quantity. In the U.S.,
there is considerable heated political debate over whether
to regulate agricultural runoff or to mandate wetlands and
endangered species protection. Partly in response, watershed
and community action groups in the U.S. and abroad are becoming
more involved in protecting local water resources.
Ecosystem needs for freshwater are broadly affected by human
activities.
Due to the finite nature of water resources,
there is a constant trade-off between meeting human and environmental
freshwater needs. Water taken from a watershed for municipal
drinking water supplies, for example, can affect the habitat
and health of local species. Indirect impacts of human activities
on ecosystem freshwater needs are common. Habitat degradation,
urbanization, pollution, and introduction of foreign species
can all adversely impact the ability for ecosystems to receive
an adequate quantity and quality of freshwater.
As society recognizes the value of ecosystem services and
natural capital, environmental needs for freshwater are receiving
higher priority.
Often, and especially in times of severe
shortage, human needs are given immediate priority over those
of the environment. However, there is increasing recognition
for the social and economic value provided by the environment
and various ecosystem services. Through this recognition of
value, environmental needs are receiving more attention. A
1997 report titled “The Value of the World’s Ecosystem
Services and Natural Capital” placed the annual value
of the earth’s natural storage and purification of water
at $2.3 trillion. Annual wetlands services received an even
higher value of $4.7 trillion.(18)
Governments, institutions, and businesses worldwide have responded
by giving environmental concerns a higher priority when making
key water-related decisions.
Freshwater Regulatory Trends
Freshwater regulations
worldwide are becoming more stringent.
Worldwide, regulations
addressing freshwater quality and effluent are becoming more
stringent. Largely in response to concerns over the effects
of water quality on public and ecosystem health, governments
are pursuing a variety of regulatory approaches for reducing
water pollution. Techniques include tighter discharge limits
for pollutants and nutrients, technology requirements, water
use restrictions, and effluent rights trading. Given the increasing
pressures on many watersheds and the growing research on public
and ecosystem health effects of water quality, it is likely
that this trend will persist.
Jurisdictions in many countries are restructuring freshwater
subsidies.
Government subsidies for freshwater have
often been designed to encourage use of water resources to
spur development and agricultural production. However, as
shortages have increased, these subsidies have been reexamined.
In some areas, subsidies have been restructured to provide
incentives for conservation, efficiency, and watershed protection.
The price of water, when reflective of its true cost or value,
can encourage responsible use.
In Israel, much discussion has occurred
over how best to regulate the use of its water resources,
which historically have been heavily subsidized. Because subsidies
have prevented prices from rising as supplies dwindle, one
of the country’s primary aquifers has been drawn down
to the critical “red line” level. The country’s
Infrastructure Minister is now pushing for a complete phase-out
of agricultural water subsidies to increase financial incentives
for conservation.(19)
Regulatory efforts are increasingly focusing on watershed-based
management approaches.
Watersheds vary significantly in the amount
of water they produce and the types of activities they support
both on-site and downstream. Many jurisdictions are turning
to watershed-based water management as a way to deliver more
effective, locally-tailored solutions. In the U.S., regulatory
agencies are exploring watershed-based approaches to water
quality protection. For example, Total Maximum Daily Load
(TMDL) approaches establish discharge limits for local sources
based on watershed health and assimilative capacity for pollutants.
The European Union (EU) officially adopted the EU Water Framework
Directive (WFD) in September 2000, which aims to improve water
quality in all EU water bodies through coordinated watershed
management.(20)
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