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Aquifer committees and groundwater over-exploitation. Case Study: The State of Guanajuato Mexico. The state of Guanajuato. Area: 30,768 km 2 of which 83% belong to the Lerma Chapala Basin (44% of the area of the basin). Population: 4.7 million 3.1% GNP of the country 480,107 irrigated - PowerPoint PPT Presentation
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Aquifer committees and
groundwater over-exploitation
Case Study:
The State of Guanajuato
Mexico
The state of Guanajuato
Area: 30,768 km2 of which 83%
belong to the Lerma Chapala
Basin (44% of the area of the
basin). Population: 4.7 million 3.1% GNP of the country 480,107 irrigated
ha (60% of it with
groundwater) Severe groundwater
exploitation problems
Groundwater exploitation in the
Lerma Chapala Basin
Red areas are
overexploited Darker blue in
balance Light blue under
used Note the state of
Guanajuato (Most
red areas)
How is the water used?
Agriculture (%)
Industry (%)
Public (urban & rural) (%)
Surface water 99.73 0.00 0.27
Groundwater 83.20 1.80 15.00
Global water use
87.81 1.30 10.89
Intense groundwater use
All aquifers are being mined and water extractions are still increasing (4000
MCM/year with a deficit of 1250 MCM/year) High productivity and forward-linked export agriculture. Growing urban and industrial water needs
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Deficit
Intense water use
Number of wells is still increasing
year
Deep
wells
Consequences of overexploitation
Average aquifer decline of 2.03 m/year
(with extremes of 5 m/year) Increasing pumping costs Decline in groundwater quality Subsidence (up to 3 cm/year)
Subsidence
What has been done before to regulate
groundwater?
Historical responses to regulate groundwater
– Vedas bans on new wells
– 1956 (Groundwater users are required to get
permits/concessions)
– Since the new water law (1992) regularization of groundwater
concessions (REPDA)
What has been done before to
regulate groundwater?
Current programs to register wells with an annual volumetric concession.
BUT
Ineffective in controlling groundwater exploitation
What is being done
aquifer management
programs
raise agricultural productivity
import water
efficiently satisfy growing public
needs
preserve sources and ecosystems
rescue water volumes
reclaimwastewater
reform financial structures
improve and sustain human
capacities
promote good- practices-enabling
social values
implement adequate
technology
improve institutional
settings
implement water exchange schemes
What are COTAS
MSP’s (Multi Stakeholder
Platforms) at aquifer level aimed
at organizing users in aquifer
management councils to reach
agreement on reductions in
extractions
What are COTAS
All water users of an aquifer can
become a member of COTAS,
multi-sectoral (1997-2000) 14 COTAS + 1
coordinating institution CEH
(Consejo Estatal Hidraulico)
Guanajuato
Structure of the COTAS
Technical Group
TECHNICAL EXPERTISE
Consultative Group
GOVERNMENTAL SUPPORT
Technical Committee - Guanajuato State’s
Trust for Social Participation in Water
Management(FIPASMA)
General Assembly
Directive Board
Manager
Administrative Suppport
COTASWater Technical Council
SOCIETY(Organized Water Users)
Technical support
Outputs of COTAS
0
5
10
15
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
COTAS installed Mathematical models completed
Economic assessment performed GW Management Programs in progress
1. Technical support to users
2. Studies and mathematical models of all aquifers
3. Institutional development
4. Communication of a “water culture”
5. User-oriented services
Challenges and opportunities
Challenges
– Low participation (2-3% of total users)
– Lack of legal faculties (no enforcement faculties)= works on
the good will of users
– Has had little effect on groundwater extraction levels
Challenges and opportunities
Opportunities
– Strong state government support (CEAG)
– Increasing awareness of users
– 15 formed and functioning institutions
Lessons learned
Participation is difficult when users don’t see direct benefits. Is 1000 or more users for one COTAS too much? The lack of legal power to enforce control and measures is an
important constraint. COTAS could play a role in titling, eg, through
responsibility and supervision of group concessions. User awareness is slowly increasing; this creates a base for action.
Water use in agriculture
Rationale: higher irrigation
efficiency will reduce
groundwater use
Programs
– Modernization of
groundwater irrigation
systems
– Plot leveling
Irrigation system Application Efficiency (%)
Earthen Channels 40%
Low Pressure Systems 60-65%
Sprinkler Irrigation 75-80%
Drip Irrigation 85-90%
Farmer applies for subsidies for
improving his irrigation technology
(requirements)
- Legal groundwater use permit
- Contribution of the farmer
(10%-50% of total costs)
- With the new project flow
meters are installed on pumps
How does it work
State Secretary of Agriculture (SDA)
reviews the application The project gets approved and
installed Farmers are responsible for the proper
installation of technology, if it is not
well installed the state does not pay. Subsides get liberated (paid by the
federal and state governments when
to work is approved and completed)
How does it work
Results of the programs
Total investment 1,2 million
dollar Benefited users 35,500 Hectares 173,000 ha Effects
– More efficient
groundwater use
– Higher agricultural
outputs
– No significant
groundwater use
reductions
Lessons
Increasing irrigation
efficiency raises
agricultural production but
does not necessarily
decrease groundwater
exploitation
Raising irrigation efficiency
to reduce groundwater use
is only effective if there is
strict control over pumped
groundwater volumes
Energy pricing
Concessioned wells receive
energy subsidy up to
concessioned volume -
enforcement difficult. All power connections for
wells require proof of
concession title. Energy tariff fixed at Mex$
0.30 (US$ 0.0316) per kWh
up to annual energy
consumption limit based
on concessioned volume.
Energy pricing
Supply manipulation
options unfeasible:
– restrictions on new
connections
– caps on capacity or
amperage, and
– reductions in hours of
power supply Pricing options...
Conclusions
Groundwater management is a
key challenge that requires
regulatory and participatory
approaches coupled with
changes in demand behavior
of pumpers.
Institutions have to work
together with each other and
with the users to reach
agreements on how to reduce
groundwater use.
Conclusions
The enabling legal and human
resources to impose strict control
are not always available so other
options have to be devised.
The options are many… but
which one(s) will work?
Can different strategies be
combined to fit the specific
needs established by a specific
context?
Acknowledgement
This case study is based on:
Jaime D. Hoogesteger van Dijk
‘The Underground; Understanding the failure of intitutional
responses to reduce groundwater exploitation in Guanajuato’
(Wageningen University, The Netherlands)
Pictures made available by Jaime Hoogesteger van Dijk.
With special thanks to:
the CEAG (www.guanajuato.gob.mx/ceag/) and SDA for making
the information available.