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The United Nations (UN) 1977 Water Conference at Mar del Plata (MDP) sought to avoid a water crisis of global dimensions by 2000 and to ensure an adequate supply of good quality water to meet socioeconomic needs. While much has been achieved, the MDP goals are not yet realised. Unsafe, or perceived to be unsafe, drinking water still affects at least 2 billion people, unsafe sanitation affects more than 4 billion people, and billions face severe water scarcity for at least part of the year. At the mid-point of the 2018-2028 International Decade for Action, 'Water for Sustainable Development', the UN 2023 Water Conference in New York City (NYC) offers a unique opportunity to review progress on global water goals, including the Sustainable Development Goals (SDGs), especially SDG 6 and its targets. Here, we document the global goals and progress from MDP to NYC and highlight priorities to deliver on the MDP goals and beyond.
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Goals, Progress and Priorities from Mar del
Plata in 1977 to New York in 2023^
R. Quentin Grafton
, Asit K. Biswas
, Hilmer Bosch
, Safa
, Joyeeta Gupta
, Aromar Revi
, Neha Sami
and Cecilia Tortajada
Crawford School of Public Policy, Australian National University,
132 Lennox Crossing, Acton, ACT 2601, Australia.
University of Glasgow, 1 Normal Avenue, Glasgow, G13 1FF,
United Kingdom.
Amsterdam Institute for Social Science Research, University of
Amsterdam, Nieuwe Achtergracht 166, Amsterdam, 1018 WV,
The Netherlands.
The School of Geography and the Environment, University of Oxford,
South Parks Road, Oxford, OX1 3QY, United Kingdom.
Indian Institute for Human Settlements, 2nd Main Road,
Sadashivanagar, Bengaluru, 560 080, Karnataka, India.
School of Interdisciplinary Studies, College of Social Sciences,
University of Glasgow, Rutherford/McCowan Building, Crichton
University Campus, Dumfries, DG1 4ZL, United Kingdom.
**Corresponding author e-mail:,
Contributing authors are listed in alphabetical order:;;; ;;;
^: A revised version of this manuscript has been accepted for publication
in Nature Water
The United Nations (UN) 1977 Water Conference at Mar del Plata (MDP)
sought to avoid a water crisis of global dimensions by 2000 and to
ensure an adequate supply of good quality water to meet socio-economic
needs. While much has been achieved, the MDP goals are not yet realised.
Unsafe, or perceived to be unsafe, drinking water still affects at least 2
billion people, unsafe sanitation affects more than 4 billion people, and
billions face severe water scarcity for at least part of the year. At the
mid-point of the 2018
2028 International Decade for Action, ‘Water for
Sustainable Development’, the UN 2023 Water Conference in New York
City (NYC) offers a unique opportunity to review progress on global water
goals, including the Sustainable Development Goals (SDGs), especially
SDG 6 and its targets. Here, we document the global goals and progress from
MDP to NYC and
highlight priorities to deliver on the MDP goals and
SDGs, justice, WASH, pollution, water quality, water
pricing, safe water, water-use efficiency, infrastructure, UN Water
Despite a 5000-year history of water governance
, the world’s first
global conference on water
was not held until 1977 in Mar del Plata
(MDP), Argentina - the United Nations (UN) Water Conference (Fig.
1). MDP was the first gathering of governments at a high political level
to respond comprehensively to multiple global water agendas
. Its focus
was to ensure that all people, irrespective of their state of development
and social and economic condition, had access to water in the
appropriate quantity and quality to cover their basic needs
The MDP water agenda was carried forward in the International
Conference on Water and the Environment (ICWE) in Dublin (1992),
and the World Summit on Sustainable Development (WSSD) in
Johannesburg (2002). Multiple UN initiatives have focused on similar
global actions and outcomes, including the Millennium Development
Goals (MDGs, 20002015); Sustainable Development Goals (SDGs,
20152030); and the High-Level Panel on Water (HLPW, 201518)
(Fig. 1). Many parallel local, regional (e.g., Arab Water Forum), and
global (e.g., World Water Forum, World Water Week) water-related
forums have also emerged since 1977. Here, we review the goals and
progress up to the UN 2023 Water Conference in New York City (NYC)
and highlight three priorities for consideration and action.
Goals, then and now
Between 1977 and 2023, the world’s human population doubled to 8
billion. Urbanisation, agricultural expansion, industrial development,
pollution, and climate change, have all placed enormous pressure on
water resources. Since MDP,
water has become scarcer per person, and
more polluted, and its availability in sufficient volumes and for
essential uses, including ecosystem integrity, is threatened by climate
. The increasing global water insecurity
imposes high
environmental and economic costs9–12 and magnifies risks13.
Fig 1: Timeline of key UN Water-related Initiatives 1975-2030
A crucial ongoing global goal has been to provide clean water and
adequate sanitation services for all. Many other water goals that began
at MDP have been retained and are part of multiple SDG Targets (Fig.
2a). Some ongoing goals include access to improved sources of water
and better sanitation services for all; better water data for improved
decision-making; increased co-operation from the transboundary to the
community level; reduced water pollution; and investment and
innovation in water-related (primarily grey) infrastructure. These are
within SDG 6 (Clean Water and Sanitation) and SDG 11 (Housing).
Other water-related issues, such as gender (highlighted at ICWE, 1992),
agricultural water use, conflict zones, and desertification (highlighted at
MDP, 1977) have, respectively, been subsumed into SDG 5 (Gender
Equality), SDG 2 (Zero Hunger), SDG 16 (Peace, Justice, and Strong
Institutions), and SDG 15 (Desertification).
Fig. 2a Connecting the goals of UN-Water Initiatives: Mar del
Plata to New York City; Fig 2b. Word clouds representing the
often-used words with conference reports (data extracted from
respective conference reports).
In 1997, the UN member states adopted the Watercourses Convention.
The convention highlighted the need to share water equitably and
optimally between riparian nations to counter the prevalent notions of
absolute territorial sovereignty and absolute integrity of state territory.
Notably, the Watercourses Convention did not include the human right
to water. The international human right to water and sanitation was
recognised in 2002 by the United Nations Committee on Economic,
Cultural and Social Rights (General Comment No. 15)
and, in 2010, in
Resolution 64/292, the UN General Assembly declared water and
sanitation as a human right. These recognitions have not yet been
sufficient to ensure clean water for all at an affordable price, including
the impoverished, marginalised, many Indigenous peoples,
and those
in remote locations
in both the global North and South
Colonisation legacies within law and practices have left many low-
income countries with water ‘ownership’ patterns tied to land
ownership18 that impede water access and sharing. For example, while the
South African Constitution acknowledges customary law, this law is not
mentioned in the National Water Act (1998). Thus, customary water rights
are frequently overlooked, and apartheid-era water rights continue under the
Existing Lawful Use water entitlements19. Regulatory patterns in former
colonial states have also promoted a preference for ‘full permanent
sovereignty’ over natural resources, thus reinforcing competing interests
between countries19.
Since MDP,
water priorities have broadened from a focus on finance and
grey infrastructure for water access to a greater emphasis on the
, especially climate change (Fig. 2b).
her vital priorities
include: responding to sovereignty and water sharing between nations;
the water-energy-food nexus
; water governance challenges from the
local to the global
; freshwater ecosystem losses
; conservation of
green infrastructure
; water’s gender and social dimensions
; private
sector provision of water services; water pricing
; adaptation
; civil
society’s participation in decision-making processes
, and the multiple
values of water
Progress on delivery of global water goals is mixed. For example, Water,
Sanitation and Hygiene (WASH) was targeted in: MDP (1977) as
‘Provision of drinking water and sanitation for all in 1990’; in MDG
Target 7.C (2000) as ‘Reduce by half the proportion of people who
were not able to reach or afford safe drinking water compared to 1990’,
and ‘Halve by 2015 the proportion of people without access to improved
sources of drinking water and improved sources of sanitation’; in WSSD
(2002) as ‘To halve by 2015 the proportion of people without access to
basic sanitation compared to 1990’; and in SDG 6 (2015) as ‘Ensure
availability and sustainable management of water and sanitation for all
by 2030’. These WASH goals have either not been achieved or are
. Failure to meet global water goals goes beyond WASH, and
their progress is detailed below.
Water supply and sanitation
In 2020, some 5.8 billion people had access to safely managed drinking
water services, about 70% of the world’s population which is a 2 billion
increase since 2000
. Yet, less than 30% of Africans have access to
safely managed drinking water services compared to more than 90% of
North Americans and Europeans (Table 1). At the current rate of
progress (Fig. 3), many regions in the global North or South will not
achieve SDG Target 6.1: “By 2030, achieve universal and equitable
access to safe and affordable drinking water for all”
Table 1 Access to safely managed water supply and sanitation:
average vs weighted average by population (data source:
WHO/UNICEF Joint Monitoring Programme)
About 60% of the world’s population in 2020 had access to safely
managed sanitation services. Yet some 1.7 billion people still lack basic
sanitation services, and at least half a billion people are forced to
defecate in the open. Further, within countries access is inequitable, with
rural regions having 26% lower coverage than urban regions
. At the
current rate of progress (Fig. 3), the world will not achieve SDG Target
: “By 2030, achieve access to adequate and equitable sanitation and
hygiene for all and end open defecation, paying special attention to the
needs of women and girls and those in vulnerable situations”.
Fig. 3 Worldwide progress towards access to safely managed
drinking water and sanitation. Figure includes average and weighted
average by population (Data Source: WHO/UNICEF Joint
Monitoring Programme)
Water quality
Water quality contributes to water scarcity and is a critical concern for
water security
, noting that water pollution arises from multiple
anthropogenic and natural sources
Global water quality data is limited, particularly in Africa and parts
of Asia and Latin America
. Thus, it is difficult to determine, at a
global scale, progress towards SDG Target 6.3: “By 2030, improve
water quality by reducing pollution, eliminating dumping and
minimising release of hazardous chemicals and materials, halving the
proportion of untreated wastewater and substantially increasing
recycling and safe reuse globally”. Notwithstanding data limitations,
the UN Environment Programme concludes that surface water quality
has declined due to pollution in many of the rivers of Latin America,
Africa, and Asia
In some regions, there have been notable improvements in water quality,
especially in the global North and, most recently, in China
. The
water quality of the Rhine River improved substantially between 1945
and 2008
and had ‘more or less’ stable water quality from 2008-2020
Despite this progress, some freshwater ecosystems in the European
Union continue to degrade with pollution from chemicals and nutrients,
exacerbated by water withdrawals
The Ganges River (Ganga) supports more than 600 million people
and many bio-diverse ecosystems, yet it is one of the world’s most
polluted rivers. The Government of India’s Ganga Action Plan (GAP)
highlights the challenge of effectively responding to water pollution
at scale. The GAP was launched in 1986 and became the National
Mission for Clean Ganga in 2016, currently supported with USD one
billion from the World Bank to build institutional capacity and
undertake infrastructure investments
. Yet, multiple long-standing
challenges exist for a clean Ganga
that include implementation
delays; irregular release of funds; confusion over the roles of different
government institutions; and irregular monitoring. Consequently,
claims of improvement in Ganga’s water quality remain
Water use efficiency
The High-Level Panel on Water (HLPW) highlighted the need for:
“efficient use of water through a national policy framework that creates
incentives for water users, including irrigators, to not waste or pollute
water, and promote its reuse”
. This idea is frequently applied to
irrigated agriculture with the goal to increase irrigation efficiency
the ratio of water supporting beneficial plant growth to the total water
withdrawal). Water efficiency has been prioritised because irrigation
accounts for about 70% of blue water (e.g., freshwater lakes, rivers, and
aquifers) withdrawals and more than 80% of blue water consumption
Increased irrigation efficiency has been promoted to increase crop yields
and to respond to a more than doubling of global irrigated areas over the
past 60 years
. Higher irrigation efficiency helps farmers to increase
crop production. However, this increase is frequently associated with
reduced water availability elsewhere
because greater beneficial water
consumption promotes a ‘rebound effect’ that increases irrigation water
and reduces the return flow of water from farmers’ fields to
streams, rivers, and aquifers. Consequently, without additional actions
such as limits on water consumption
, increasing water-use efficiency
alone will not achieve SDG Target 6.4: “By 2030, substantially increase
water-use efficiency across all sectors and ensure sustainable
withdrawals and supply of freshwater to address water scarcity and
substantially reduce the number of people suffering from water
Transboundary water treaties
Bilateral water treaties have existed since the 25th century BCE; today,
they number some 600. These treaties have been critical in shaping
principles of water law at a global level, that is: absolute territorial
sovereignty (countries have absolute rights to use the water flowing in
their territory, empowering upstream states); and the absolute integrity
of state territory (countries have the right to receive the same quality and
quantity of flows through time, benefitting downstream states)
Amending existing water laws is critical to ensure sustainable
governance of water. At the global scale, three water conventions relate
to transboundary waters, although none adequately responds to the
hydrological impacts of climate change. First, the Ramsar Agreement on
Wetlands (1971) had 172 contracting parties and entered into force in
1975 with the intent to stem the loss and degradation of wetlands of
international importance. Second, the UN Economic Commission for
Europe (UNECE) 1992 Water Convention had 46 contracting parties
and was later opened for ratification by non-UNECE members. Third,
the 1997 Watercourses Convention had 37 contracting parties and
entered into force in 2014
The 1992
Water Convention is notable for its focus on water pollution,
and its follow-up protocol responds to concerns over human health
related to drinking water and sanitation. The 1997 Watercourses
Convention is important because it shifted long-standing notions of
national sovereignty towards ‘do no harm’ to other states and to
equitable water sharing based on specified criteria and weights
agreed to by riparian countries
While hundreds of treaties govern
transboundary waters, many countries are reluctant to ratify the
Watercourses Convention, which specifies the need for equitable
sharing. Transboundary co-operation, as envisaged by the UN and
UNECE Water Conventions, has only progressed to a limited extent
and, consequently, is limited to specific water issues
. Thus, much
remains to be accomplished to achieve SDG Target 6.5: “By 2030,
implement integrated water resources management at all levels,
including through transboundary co-operation as appropriate.”
Protect and restore water-related ecosystems
About 35 percent of the world’s wetlands were lost between 1970 and
2015. This loss negatively impacts ecosystems, biodiversity, and human
welfare (Convention on Wetlands 2021). While some regions, such as
North America, have performed relatively well in reducing recent
losses, others, such as Africa and Latin America, have not
Nevertheless, more wetlands are currently characterised as in a ‘fair or
good’ ecological character state than previously, and only 23% of all
wetlands are reported as being in a ‘poor’ state
. Further, Ramsar
wetlands of international importance are considered to be in better
condition than wetlands in general
Fig. 4 Global Water Withdrawals (bill. Cu. M/year), and Global
Forest Area and deforestation (mill. Ha.) (data source: FAO stat,
About 70% of the global wetland losses happened in the 20th
century, with the highest loss rates in inland and coastal wetlands areas
occurring since 1950
. The current estimated total area of wetlands is
15–16 million km
and loss rates are 0.2% per year
. Much of this loss
is associated with land-use change, but inappropriate water regulation
(drainage, water
withdrawals, salinisation, river regulation, pollution)
has also been a contributing factor.
An important contributor to the degradation of water-related ecosystems
is reduced forest cover. Deforestation changes water availability and
contributes to soil erosion, degrades water quality, and increases
flooding risks. While forest cover has recently increased in some
regions, such as North America and Northern Europe
, the global
forested area continues to decline (Fig. 4). Another critical pressure on
water ecosystems is global blue water withdrawals, which have almost
doubled since MDP (1977)
In summary, SDG Target 6.6 has not been achieved: “By 2020,
protect and restore water-related ecosystems, including mountains,
forests, wetlands, rivers, aquifers and lakes”. Nor will SDG Target 15.1
be realised without a change in business-as-usual: “[c]onservation,
restoration and sustainable use of terrestrial and inland freshwater
ecosystems and their services, in particular forests, wetlands, mountains
and drylands...”.
Data gaps
Eight of the 11 water-related indicators for SDG 6 are regularly
assessed by at least half of all countries. These indicators include
access to safe and affordable drinking water; increased water-use
efficiency; implementation of integrated water resources management;
protection of water-related ecosystems; and, international co-
operation and participation of local communities in improving water
and sanitation management. However, three
indicators - access to
sanitation, discharge of safely treated domestic and indus
trial wastewater,
and bodies of water with good ambient water quality - are not regularly
produced by most countries
. Further, only 115 countries report data
on total water access, and some (e.g., Australia and China) only
report urban water access but not rural water access (Fig. 5).
Fig. 5 Countries reporting data on access to safely managed water
supply (Data Source: WHO/UNICEF Joint Monitoring Programme
Thus, despite substantial progress, data constraints identified at MDP,
the MDGs
, and highlighted in the HLPW (2018), remain an
impediment to determining progress, identifying gaps, allocating
funding, and delivering actions linked to human development
Nevertheless, we contend that there is sufficient data to define priorities
and act.
Progress since MDP shows that there is no single approach to achieve
sustainable and equitable goals of ‘water for all’. This is because the
burdens of water insecurity are primarily realised at a local level
(e.g., droughts, floods, pollution, access and affordability, the
distribution of property rights to water in society), yet the drivers range
from local to global (e.g., trade in virtual water, climate change, income
and wealth inequalities, power imbalances within and across countries,
failure to internalise costs and historical injustice, and more)
contrast to MDP, d
elivery on global water goals, while responding to
injustice in both the global North16 and global South62, is now constrained
planetary limits
and tipping points
. Among the many priorities
available, here we highlight three for consideration at the second UN
Water Conference
: improved WASH42; investments in infrastructure
(grey, green, and soft); and a shift in values, behaviours, and incentives
Towards safe drinking water and sanitation
Realising any of the SDG goals ranging from health to gender
equality requires transformational change in access to safe water
supply and sanitation for all
. A bespoke example in urban WASH
services is Cambodia’s Phnom Penh Water Supply Authority which
began reforms in 1993 that subsequently resulted in a ten-fold increase
in its water distribution network.
This change was accomplished by a
‘Swiss cheese model’ of cumulative actions to ensure WASH access65,
than any single action. These actions included: inspired
leadership and institutional reform; a good understanding
of water
customers; a focus on reduced water losses; removal of illegal
connections; metering of all connections; a billing system that ensures
all who receive water pay for it; and donor-financed infrastructure
for potable purposes, we highlight innovations at Windhoek
a pioneer in directly providing reclaimed water67. For other
locations such as Singapore; Orange County (USA); Wulpen (Belgium);
Essex (United Kingdom); and Perth (Australia), reclaimed and/or recycled
water is an essential part of water supply
While much can be learnt
from these examples, unfortunately, these places remain an
exception. For many urban residents, bespoke water reforms are
required to overcome shortfalls. In cities like Jakarta (Indonesia)
New Delhi (India)
, and Flint (Michigan USA)
, unsafe tap water
and incomplete sanitation and wastewater treatment services, are a
norm for those who cannot afford to pay for safe water access.
In contrast to urban experiences, enabling water and sanitation in rural areas
is more difficult due to scale, demand, and dispersed infrastructure,
institutions (formal and informal), and finance
. Rural water supply
experiences from African and Asian countries suggest a need to go beyond
single source supply and ‘think beyond pipes’ to encompass diversified
sources, ranging from private water vendors to rainfall. Enhancing access
to safe water in rural areas is also linked to strengthening cultural water
values and to the conservation of blue water sources (e.g., springs, lakes,
and wetlands)
3.2 Investing in the three infrastructures
Much of the focus on delivering water infrastructure since MDP has
been on grey infrastructure (e.g., pipes, channels, treatment, buildings).
While grey infrastructure is needed in both the global South and
North, we contend that
green (e.g., floodplains, wetlands, river channels,
lakes and estuaries, soil, aquifers) and soft infrastructure (e.g.,
governance, regulation, education, incentives, and communication) are
equally important priorities.
Grey infrastructure for WASH
Annual global subsidies of some US$
320 billion are provided for
delivering WASH services. Much of this expenditure goes to existing
water services. Thus, the poorest with the least (or no) access to a
centralised water system receive minimal support. Around 56% of
subsidies go to the highest quintile households by income, and 6% go to
the lowest quintile households
. Multiple informal markets and
decentralised systems of water provision are frequently ignored within
regulated and centralised pricing and infrastructure planning processes
By 2030, approximately US$ 1.5 trillion per year of capital investments
are required for grey infrastructure, with the most needed in the global
. Hutton and Varughese
estimated that the total annual capital
costs to achieve SDG targets 6.1 and 6.2 range from US$ 74166 billion,
comprised of 37.6 billion for safe water, 19.5 billion for basic sanitation,
and 49 billion for safe faecal waste management.
The investments required to deliver SDG 6 will need multiple forms of
financing. Yet, global private sector investments in greywater
infrastructure in 2020 were US$ 17 billion
. To overcome this challenge,
the OECD recommends several financing pathways: improved soft
infrastructure around the delivery of WASH services, such as an
enabling environment (e.g., decrease in non-revenue water); strategic
investment planning; mobilising additional investment by governments;
restructuring risks and returns; and public-private partnerships leveraged
by larger public investments
Green infrastructure for WASH and more
Green infrastructure has long been practised in the water sector,
especially in conserving water catchments. For decades, cities such as
Tokyo and New York
have invested in protecting their watersheds to
maintain high-quality water supply sources
. The financial pay-off
has been a reduction in treatment, operation, and maintenance costs
A review of 309
large cities showed how degraded catchments
increased operations and maintenance costs by 53
5%, and
replacement capital costs by 44
. Further, these benefits are not
just measured in dollars; examples from Kenya show that conserving
green infrastructure, such as natural springs, can reduce child mortality
by one-quarter
Green infrastructure is increasingly acknowledged for its importance
in delivering important ecosystem services (e.g., freshwater provision,
sediment regulation, flood mitigation and hydropower
. In addition, such infrastructure also supports
cultural, recreational, and amenity values, while enabling flood
management, groundwater recharge and more
. Nature-based
investments in rain gardens, green rooves, and urban constructed
wetlands, can also offset some of the negative impacts of grey
. The
benefits of maintaining and conserving green
infrastructure are esti
mated to be worth US$3 trillion by 2050 in
avoided replacement costs for grey infrastructure
Soft infrastructure for collective action
As synthesised by the World Bank
and highlighted by the OECD
soft infrastructure reform is critical to progressing SDG 6 and other
SDG targets. According to the Water Policy Group, and others
three important failures that need to be overcome include: fragmented
water institu
tions; inadequate and inaccessible data and information; and
conflicts between
water user groups. In response to these challenges,
the World Bank has proposed a Policy, Institutions and Regulations
framework that connects data to WASH performance, reviews
existing laws and the incentives they provide, builds institutional
capacity, and establishes effective planning to respond to stresses and
. The lessons from this framework are applicable beyond
WASH but can be difficult to implement because of regulatory
capture, rent seeking, and corruption
Regulatory capture
occurs when state actors are ‘captured’ through a
process of mediated corruption
. Such capture is not necessarily illegal
and is facilitated by political donations, lobbying, ‘tit for tat’ favours,
and ‘revolving doors’ for decision-makers. This may be exacerbated by
rigid decision hierarchies
, but Singapore is an example where a top-
down corruption control has been highly effective. Singapore’s approach
has been supported by; laws (
Prevention of Corruption Act
, and
Corruption, Drug Trafficking and Other Serious Crimes
of Benefits)
), an independent judiciary, strict and timely
enforcement through the Corrupt Practice Investigation Bureau under
the Prime Minister’s Office, and a strict code of conduct for public
servants, with severe penalties for infringements.
Regulatory capture and rent-seeking influence how money is spent and
how decisions are prioritised
, noting that in some water sectors
corruption is widespread
and occurs in both the global North and
Responding to corruption r
equires bottom-up citizen vigilance
plus international and national civil society support
Anti-corruption measures must be fit for purpose. Nevertheless, we
highlight some priorities: promoting
decision-making at the scale where
it is most effective and least vulnerable to manipulation; meaningful
deliberations with all relevant stakeholders;
transparency in process and
decisions; and independent regulatory oversight.
3.3 Values, behaviours, and incentives
Water has multiple use values (e.g., WASH, agriculture, industry,
flows, etc.) observable from people’s behaviours, and non-use
or passive values
(e.g., aesthetic, spiritual, and bequest), which are not
often valued
. Measurement of these multiple values is
because without estimates of non-market values (e.g., water in rivers
lakes left in situ) and cultural values of water, decision-makers will,
typically, only consider and/or prioritise market values (e.g., water
used to produce commercial crops)
Failure to fully value water in all uses, including
in situ
uses, has
contributed to the degradation of green infrastructure that is critically
important to deliver SDG 6, among other goals. Not, or only partially
valuing water,87
and not accounting for the external costs imposed on
others from water use, such as increased salinity, reduced stream flows
from irrigation, or water-related health problems, contributes to water
misallocation. That is, too much water is allocated for purposes that
generate market values (e.g., cotton production), and too little water is
allocated for non-market needs (e.g., maintaining ecosystem services).
This problem is most transparent with formal water markets (e.g., in
Australia, Chile, China, Spain, USA) which have been effective, when
there is adequate monitoring and compliance, at reallocating water based
on the marginal willingness to pay among competing water users.
Nevertheless, if the overall cap on water withdrawals in water markets
fails to adequately consider non-market values, total water withdrawals
are economically inefficient
. Failure to ensure an appropriate initial
allocation of water rights, especially for Indigenous custodians of land
and to prioritise drinking water needs for communities located on or
nearby rivers where water rights are traded, undermines the social
licence of water markets, and increases inequities
Water regulators influence water conservation behaviours in multiple
ways. For example, rationing constrains water availability or type of use
and modifies household water conservation behaviours by requiring
users to use less water. An alternative approach is to price non-essential
water uses and to provide a free allocation for essential uses and
subsidies for low-income water users. Higher volumetric prices for those
who can afford it can provide an incentive, but not an obligation, to
conserve water
where water use is metered. More equitable water
outcomes can be supported by ensuring that additional revenues from
higher water prices are directed to water suppliers to improve services
and/or to reduce the fixed charges of poorer households. Non-market
values and future water scarcity may also be included in r
egulated water
prices. For example, in Australia; in Canberra a water abstraction
proxies the external costs of household water consumption
on downstream water users and in Sydney the volumetric price
increases by 35% when water storages fall below 60%.
In many cities in the global South there is inadequate household
coverage of centralised water services, and this is frequently
accompanied by supply interruptions
. Consequently, a proportion
of urban households, as much as 50% in some cities, either
supplement or completely obtain water independently (e.g., wells,
rivers) and/or through private water vendors. While the volumetric
price from water vendors can be much greater than centralised water
, they do offer a valuable service in cities as diverse as
Dhaka, Bangladesh
to Dar es Salaam, Tanzania
Progress on achieving the goals at MDP, the MDGs, and SDGs is mixed.
Substantial progress has occurred on WASH, important transboundary
agreements and conventions have come into force (e.g., Ramsar,
Watercourses Convention) and some measures of water quality have
improved, mostly in the global North, since MDP. Nevertheless, none of
the SDG 6 targets will be delivered by 2030, increases in water-use
efficiency (SDG Target 6.4) alone will not ensure either sustainable
water withdrawals or reduce the number of people suffering from water
scarcity, and key data gaps remain.
Decades-long trends of reductions in the global area of wetlands and
forests, coupled with ever-increasing global blue water withdrawals,
pose increasing risks for human welfare and planetary health. A failure
to achieve the key goals of the first UN Water Conference, after almost
five decades, and an increasing riskier the world will cross a critical
tipping point, demand transformational change. For the second UN
Water Conference, and beyond, we highlight the importance of three
priorities: improved WASH; much greater and better prioritised
infrastructure (grey, green, and soft) investments; and a shift in values,
behaviours, and incentives. Without these and other changes that are
bespoke to the bio-physical and socio-economic contexts where they are
applied, we will fail to deliver ‘water for all’.
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We are grateful to the Netherlands Enterprise Agency (RVO) that provided a
partial subsidy for HB, SF and NS.
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